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Socket-Options #9

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cpaasch opened this issue Aug 13, 2013 · 0 comments
Open

Socket-Options #9

cpaasch opened this issue Aug 13, 2013 · 0 comments

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@cpaasch
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cpaasch commented Aug 13, 2013

Generally, we have to check all sockopts again.

cpaasch pushed a commit that referenced this issue Aug 16, 2013
…s struct file

commit e4daf1f upstream.

The following call chain:
------------------------------------------------------------
nfs4_get_vfs_file
- nfsd_open
  - dentry_open
    - do_dentry_open
      - __get_file_write_access
        - get_write_access
          - return atomic_inc_unless_negative(&inode->i_writecount) ? 0 : -ETXTBSY;
------------------------------------------------------------

can result in the following state:
------------------------------------------------------------
struct nfs4_file {
...
  fi_fds = {0xffff880c1fa65c80, 0xffffffffffffffe6, 0x0},
  fi_access = {{
      counter = 0x1
    }, {
      counter = 0x0
    }},
...
------------------------------------------------------------

1) First time around, in nfs4_get_vfs_file() fp->fi_fds[O_WRONLY] is
NULL, hence nfsd_open() is called where we get status set to an error
and fp->fi_fds[O_WRONLY] to -ETXTBSY. Thus we do not reach
nfs4_file_get_access() and fi_access[O_WRONLY] is not incremented.

2) Second time around, in nfs4_get_vfs_file() fp->fi_fds[O_WRONLY] is
NOT NULL (-ETXTBSY), so nfsd_open() is NOT called, but
nfs4_file_get_access() IS called and fi_access[O_WRONLY] is incremented.
Thus we leave a landmine in the form of the nfs4_file data structure in
an incorrect state.

3) Eventually, when __nfs4_file_put_access() is called it finds
fi_access[O_WRONLY] being non-zero, it decrements it and calls
nfs4_file_put_fd() which tries to fput -ETXTBSY.
------------------------------------------------------------
...
     [exception RIP: fput+0x9]
     RIP: ffffffff81177fa9  RSP: ffff88062e365c90  RFLAGS: 00010282
     RAX: ffff880c2b3d99cc  RBX: ffff880c2b3d9978  RCX: 0000000000000002
     RDX: dead000000100101  RSI: 0000000000000001  RDI: ffffffffffffffe6
     RBP: ffff88062e365c90   R8: ffff88041fe797d8   R9: ffff88062e365d58
     R10: 0000000000000008  R11: 0000000000000000  R12: 0000000000000001
     R13: 0000000000000007  R14: 0000000000000000  R15: 0000000000000000
     ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
  #9 [ffff88062e365c98] __nfs4_file_put_access at ffffffffa0562334 [nfsd]
 #10 [ffff88062e365cc8] nfs4_file_put_access at ffffffffa05623ab [nfsd]
 #11 [ffff88062e365ce8] free_generic_stateid at ffffffffa056634d [nfsd]
 #12 [ffff88062e365d18] release_open_stateid at ffffffffa0566e4b [nfsd]
 #13 [ffff88062e365d38] nfsd4_close at ffffffffa0567401 [nfsd]
 #14 [ffff88062e365d88] nfsd4_proc_compound at ffffffffa0557f28 [nfsd]
 #15 [ffff88062e365dd8] nfsd_dispatch at ffffffffa054543e [nfsd]
 #16 [ffff88062e365e18] svc_process_common at ffffffffa04ba5a4 [sunrpc]
 #17 [ffff88062e365e98] svc_process at ffffffffa04babe0 [sunrpc]
 #18 [ffff88062e365eb8] nfsd at ffffffffa0545b62 [nfsd]
 #19 [ffff88062e365ee8] kthread at ffffffff81090886
 #20 [ffff88062e365f48] kernel_thread at ffffffff8100c14a
------------------------------------------------------------

Signed-off-by: Harshula Jayasuriya <[email protected]>
Signed-off-by: J. Bruce Fields <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
cpaasch pushed a commit that referenced this issue Aug 16, 2013
commit ea3768b upstream.

We used to keep the port's char device structs and the /sys entries
around till the last reference to the port was dropped.  This is
actually unnecessary, and resulted in buggy behaviour:

1. Open port in guest
2. Hot-unplug port
3. Hot-plug a port with the same 'name' property as the unplugged one

This resulted in hot-plug being unsuccessful, as a port with the same
name already exists (even though it was unplugged).

This behaviour resulted in a warning message like this one:

-------------------8<---------------------------------------
WARNING: at fs/sysfs/dir.c:512 sysfs_add_one+0xc9/0x130() (Not tainted)
Hardware name: KVM
sysfs: cannot create duplicate filename
'/devices/pci0000:00/0000:00:04.0/virtio0/virtio-ports/vport0p1'

Call Trace:
 [<ffffffff8106b607>] ? warn_slowpath_common+0x87/0xc0
 [<ffffffff8106b6f6>] ? warn_slowpath_fmt+0x46/0x50
 [<ffffffff811f2319>] ? sysfs_add_one+0xc9/0x130
 [<ffffffff811f23e8>] ? create_dir+0x68/0xb0
 [<ffffffff811f2469>] ? sysfs_create_dir+0x39/0x50
 [<ffffffff81273129>] ? kobject_add_internal+0xb9/0x260
 [<ffffffff812733d8>] ? kobject_add_varg+0x38/0x60
 [<ffffffff812734b4>] ? kobject_add+0x44/0x70
 [<ffffffff81349de4>] ? get_device_parent+0xf4/0x1d0
 [<ffffffff8134b389>] ? device_add+0xc9/0x650

-------------------8<---------------------------------------

Instead of relying on guest applications to release all references to
the ports, we should go ahead and unregister the port from all the core
layers.  Any open/read calls on the port will then just return errors,
and an unplug/plug operation on the host will succeed as expected.

This also caused buggy behaviour in case of the device removal (not just
a port): when the device was removed (which means all ports on that
device are removed automatically as well), the ports with active
users would clean up only when the last references were dropped -- and
it would be too late then to be referencing char device pointers,
resulting in oopses:

-------------------8<---------------------------------------
PID: 6162   TASK: ffff8801147ad500  CPU: 0   COMMAND: "cat"
 #0 [ffff88011b9d5a90] machine_kexec at ffffffff8103232b
 #1 [ffff88011b9d5af0] crash_kexec at ffffffff810b9322
 #2 [ffff88011b9d5bc0] oops_end at ffffffff814f4a50
 #3 [ffff88011b9d5bf0] die at ffffffff8100f26b
 #4 [ffff88011b9d5c20] do_general_protection at ffffffff814f45e2
 #5 [ffff88011b9d5c50] general_protection at ffffffff814f3db5
    [exception RIP: strlen+2]
    RIP: ffffffff81272ae2  RSP: ffff88011b9d5d00  RFLAGS: 00010246
    RAX: 0000000000000000  RBX: ffff880118901c18  RCX: 0000000000000000
    RDX: ffff88011799982c  RSI: 00000000000000d0  RDI: 3a303030302f3030
    RBP: ffff88011b9d5d38   R8: 0000000000000006   R9: ffffffffa0134500
    R10: 0000000000001000  R11: 0000000000001000  R12: ffff880117a1cc10
    R13: 00000000000000d0  R14: 0000000000000017  R15: ffffffff81aff700
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #6 [ffff88011b9d5d00] kobject_get_path at ffffffff8126dc5d
 #7 [ffff88011b9d5d40] kobject_uevent_env at ffffffff8126e551
 #8 [ffff88011b9d5dd0] kobject_uevent at ffffffff8126e9eb
 #9 [ffff88011b9d5de0] device_del at ffffffff813440c7

-------------------8<---------------------------------------

So clean up when we have all the context, and all that's left to do when
the references to the port have dropped is to free up the port struct
itself.

Reported-by: chayang <[email protected]>
Reported-by: YOGANANTH SUBRAMANIAN <[email protected]>
Reported-by: FuXiangChun <[email protected]>
Reported-by: Qunfang Zhang <[email protected]>
Reported-by: Sibiao Luo <[email protected]>
Signed-off-by: Amit Shah <[email protected]>
Signed-off-by: Rusty Russell <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
duncanje pushed a commit to bluca/mptcp that referenced this issue Sep 27, 2013
On architectures where cputime_t is 64 bit type, is possible to trigger
divide by zero on do_div(temp, (__force u32) total) line, if total is a
non zero number but has lower 32 bit's zeroed. Removing casting is not
a good solution since some do_div() implementations do cast to u32
internally.

This problem can be triggered in practice on very long lived processes:

  PID: 2331   TASK: ffff880472814b00  CPU: 2   COMMAND: "oraagent.bin"
   #0 [ffff880472a51b70] machine_kexec at ffffffff8103214b
   multipath-tcp#1 [ffff880472a51bd0] crash_kexec at ffffffff810b91c2
   multipath-tcp#2 [ffff880472a51ca0] oops_end at ffffffff814f0b00
   multipath-tcp#3 [ffff880472a51cd0] die at ffffffff8100f26b
   multipath-tcp#4 [ffff880472a51d00] do_trap at ffffffff814f03f4
   multipath-tcp#5 [ffff880472a51d60] do_divide_error at ffffffff8100cfff
   multipath-tcp#6 [ffff880472a51e00] divide_error at ffffffff8100be7b
      [exception RIP: thread_group_times+0x56]
      RIP: ffffffff81056a16  RSP: ffff880472a51eb8  RFLAGS: 00010046
      RAX: bc3572c9fe12d194  RBX: ffff880874150800  RCX: 0000000110266fad
      RDX: 0000000000000000  RSI: ffff880472a51eb8  RDI: 001038ae7d9633dc
      RBP: ffff880472a51ef8   R8: 00000000b10a3a64   R9: ffff880874150800
      R10: 00007fcba27ab680  R11: 0000000000000202  R12: ffff880472a51f08
      R13: ffff880472a51f10  R14: 0000000000000000  R15: 0000000000000007
      ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
   multipath-tcp#7 [ffff880472a51f00] do_sys_times at ffffffff8108845d
   multipath-tcp#8 [ffff880472a51f40] sys_times at ffffffff81088524
   multipath-tcp#9 [ffff880472a51f80] system_call_fastpath at ffffffff8100b0f2
      RIP: 0000003808caac3a  RSP: 00007fcba27ab6d8  RFLAGS: 00000202
      RAX: 0000000000000064  RBX: ffffffff8100b0f2  RCX: 0000000000000000
      RDX: 00007fcba27ab6e0  RSI: 000000000076d58e  RDI: 00007fcba27ab6e0
      RBP: 00007fcba27ab700   R8: 0000000000000020   R9: 000000000000091b
      R10: 00007fcba27ab680  R11: 0000000000000202  R12: 00007fff9ca41940
      R13: 0000000000000000  R14: 00007fcba27ac9c0  R15: 00007fff9ca41940
      ORIG_RAX: 0000000000000064  CS: 0033  SS: 002b

Cc: [email protected]
Signed-off-by: Stanislaw Gruszka <[email protected]>
Signed-off-by: Peter Zijlstra <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>
duncanje pushed a commit to bluca/mptcp that referenced this issue Sep 27, 2013
Cancel work of the xfs_sync_worker before teardown of the log in
xfs_unmountfs.  This prevents occasional crashes on unmount like so:

PID: 21602  TASK: ee9df060  CPU: 0   COMMAND: "kworker/0:3"
 #0 [c5377d28] crash_kexec at c0292c94
 multipath-tcp#1 [c5377d80] oops_end at c07090c2
 multipath-tcp#2 [c5377d98] no_context at c06f614e
 multipath-tcp#3 [c5377dbc] __bad_area_nosemaphore at c06f6281
 multipath-tcp#4 [c5377df4] bad_area_nosemaphore at c06f629b
 multipath-tcp#5 [c5377e00] do_page_fault at c070b0cb
 multipath-tcp#6 [c5377e7c] error_code (via page_fault) at c070892c
    EAX: f300c6a8  EBX: f300c6a8  ECX: 000000c0  EDX: 000000c0  EBP: c5377ed0
    DS:  007b      ESI: 00000000  ES:  007b      EDI: 00000001  GS:  ffffad20
    CS:  0060      EIP: c0481ad0  ERR: ffffffff  EFLAGS: 00010246
 multipath-tcp#7 [c5377eb0] atomic64_read_cx8 at c0481ad0
 multipath-tcp#8 [c5377ebc] xlog_assign_tail_lsn_locked at f7cc7c6e [xfs]
 multipath-tcp#9 [c5377ed4] xfs_trans_ail_delete_bulk at f7ccd520 [xfs]
multipath-tcp#10 [c5377f0c] xfs_buf_iodone at f7ccb602 [xfs]
multipath-tcp#11 [c5377f24] xfs_buf_do_callbacks at f7cca524 [xfs]
multipath-tcp#12 [c5377f30] xfs_buf_iodone_callbacks at f7cca5da [xfs]
multipath-tcp#13 [c5377f4c] xfs_buf_iodone_work at f7c718d0 [xfs]
multipath-tcp#14 [c5377f58] process_one_work at c024ee4c
multipath-tcp#15 [c5377f98] worker_thread at c024f43d
multipath-tcp#16 [c5377fbc] kthread at c025326b
multipath-tcp#17 [c5377fe8] kernel_thread_helper at c070e834

PID: 26653  TASK: e79143b0  CPU: 3   COMMAND: "umount"
 #0 [cde0fda0] __schedule at c0706595
 multipath-tcp#1 [cde0fe28] schedule at c0706b89
 multipath-tcp#2 [cde0fe30] schedule_timeout at c0705600
 multipath-tcp#3 [cde0fe94] __down_common at c0706098
 multipath-tcp#4 [cde0fec8] __down at c0706122
 multipath-tcp#5 [cde0fed0] down at c025936f
 multipath-tcp#6 [cde0fee0] xfs_buf_lock at f7c7131d [xfs]
 multipath-tcp#7 [cde0ff00] xfs_freesb at f7cc2236 [xfs]
 multipath-tcp#8 [cde0ff10] xfs_fs_put_super at f7c80f21 [xfs]
 multipath-tcp#9 [cde0ff1c] generic_shutdown_super at c0333d7a
multipath-tcp#10 [cde0ff38] kill_block_super at c0333e0f
multipath-tcp#11 [cde0ff48] deactivate_locked_super at c0334218
multipath-tcp#12 [cde0ff58] deactivate_super at c033495d
multipath-tcp#13 [cde0ff68] mntput_no_expire at c034bc13
multipath-tcp#14 [cde0ff7c] sys_umount at c034cc69
multipath-tcp#15 [cde0ffa0] sys_oldumount at c034ccd4
multipath-tcp#16 [cde0ffb0] system_call at c0707e66

commit 11159a0 added this to xfs_log_unmount and needs to be cleaned up
at a later date.

Signed-off-by: Ben Myers <[email protected]>
Reviewed-by: Dave Chinner <[email protected]>
Reviewed-by: Mark Tinguely <[email protected]>
duncanje pushed a commit to bluca/mptcp that referenced this issue Sep 27, 2013
Cancel work of the xfs_sync_worker before teardown of the log in
xfs_unmountfs.  This prevents occasional crashes on unmount like so:

PID: 21602  TASK: ee9df060  CPU: 0   COMMAND: "kworker/0:3"
 #0 [c5377d28] crash_kexec at c0292c94
 multipath-tcp#1 [c5377d80] oops_end at c07090c2
 multipath-tcp#2 [c5377d98] no_context at c06f614e
 multipath-tcp#3 [c5377dbc] __bad_area_nosemaphore at c06f6281
 multipath-tcp#4 [c5377df4] bad_area_nosemaphore at c06f629b
 multipath-tcp#5 [c5377e00] do_page_fault at c070b0cb
 multipath-tcp#6 [c5377e7c] error_code (via page_fault) at c070892c
    EAX: f300c6a8  EBX: f300c6a8  ECX: 000000c0  EDX: 000000c0  EBP: c5377ed0
    DS:  007b      ESI: 00000000  ES:  007b      EDI: 00000001  GS:  ffffad20
    CS:  0060      EIP: c0481ad0  ERR: ffffffff  EFLAGS: 00010246
 multipath-tcp#7 [c5377eb0] atomic64_read_cx8 at c0481ad0
 multipath-tcp#8 [c5377ebc] xlog_assign_tail_lsn_locked at f7cc7c6e [xfs]
 multipath-tcp#9 [c5377ed4] xfs_trans_ail_delete_bulk at f7ccd520 [xfs]
multipath-tcp#10 [c5377f0c] xfs_buf_iodone at f7ccb602 [xfs]
multipath-tcp#11 [c5377f24] xfs_buf_do_callbacks at f7cca524 [xfs]
multipath-tcp#12 [c5377f30] xfs_buf_iodone_callbacks at f7cca5da [xfs]
multipath-tcp#13 [c5377f4c] xfs_buf_iodone_work at f7c718d0 [xfs]
multipath-tcp#14 [c5377f58] process_one_work at c024ee4c
multipath-tcp#15 [c5377f98] worker_thread at c024f43d
multipath-tcp#16 [c5377fbc] kthread at c025326b
multipath-tcp#17 [c5377fe8] kernel_thread_helper at c070e834

PID: 26653  TASK: e79143b0  CPU: 3   COMMAND: "umount"
 #0 [cde0fda0] __schedule at c0706595
 multipath-tcp#1 [cde0fe28] schedule at c0706b89
 multipath-tcp#2 [cde0fe30] schedule_timeout at c0705600
 multipath-tcp#3 [cde0fe94] __down_common at c0706098
 multipath-tcp#4 [cde0fec8] __down at c0706122
 multipath-tcp#5 [cde0fed0] down at c025936f
 multipath-tcp#6 [cde0fee0] xfs_buf_lock at f7c7131d [xfs]
 multipath-tcp#7 [cde0ff00] xfs_freesb at f7cc2236 [xfs]
 multipath-tcp#8 [cde0ff10] xfs_fs_put_super at f7c80f21 [xfs]
 multipath-tcp#9 [cde0ff1c] generic_shutdown_super at c0333d7a
multipath-tcp#10 [cde0ff38] kill_block_super at c0333e0f
multipath-tcp#11 [cde0ff48] deactivate_locked_super at c0334218
multipath-tcp#12 [cde0ff58] deactivate_super at c033495d
multipath-tcp#13 [cde0ff68] mntput_no_expire at c034bc13
multipath-tcp#14 [cde0ff7c] sys_umount at c034cc69
multipath-tcp#15 [cde0ffa0] sys_oldumount at c034ccd4
multipath-tcp#16 [cde0ffb0] system_call at c0707e66

commit 11159a0 added this to xfs_log_unmount and needs to be cleaned up
at a later date.

Signed-off-by: Ben Myers <[email protected]>
Reviewed-by: Dave Chinner <[email protected]>
Reviewed-by: Mark Tinguely <[email protected]>
duncanje pushed a commit to bluca/mptcp that referenced this issue Sep 27, 2013
…ble code

Commit 6889125
(cpufreq/powernow-k8: workqueue user shouldn't migrate the kworker to another CPU)
causes powernow-k8 to trigger a preempt warning, e.g.:

  BUG: using smp_processor_id() in preemptible [00000000] code: cpufreq/3776
  caller is powernowk8_target+0x20/0x49
  Pid: 3776, comm: cpufreq Not tainted 3.6.0 multipath-tcp#9
  Call Trace:
   [<ffffffff8125b447>] debug_smp_processor_id+0xc7/0xe0
   [<ffffffff814877e7>] powernowk8_target+0x20/0x49
   [<ffffffff81482b02>] __cpufreq_driver_target+0x82/0x8a
   [<ffffffff81484fc6>] cpufreq_governor_performance+0x4e/0x54
   [<ffffffff81482c50>] __cpufreq_governor+0x8c/0xc9
   [<ffffffff81482e6f>] __cpufreq_set_policy+0x1a9/0x21e
   [<ffffffff814839af>] store_scaling_governor+0x16f/0x19b
   [<ffffffff81484f16>] ? cpufreq_update_policy+0x124/0x124
   [<ffffffff8162b4a5>] ? _raw_spin_unlock_irqrestore+0x2c/0x49
   [<ffffffff81483640>] store+0x60/0x88
   [<ffffffff811708c0>] sysfs_write_file+0xf4/0x130
   [<ffffffff8111243b>] vfs_write+0xb5/0x151
   [<ffffffff811126e0>] sys_write+0x4a/0x71
   [<ffffffff816319a9>] system_call_fastpath+0x16/0x1b

Fix this by by always using work_on_cpu().

Signed-off-by: Andreas Herrmann <[email protected]>
Cc: [email protected]
Signed-off-by: Rafael J. Wysocki <[email protected]>
duncanje pushed a commit to bluca/mptcp that referenced this issue Sep 27, 2013
A rescue thread exiting TASK_INTERRUPTIBLE can lead to a task scheduling
off, never to be seen again.  In the case where this occurred, an exiting
thread hit reiserfs homebrew conditional resched while holding a mutex,
bringing the box to its knees.

PID: 18105  TASK: ffff8807fd412180  CPU: 5   COMMAND: "kdmflush"
 #0 [ffff8808157e7670] schedule at ffffffff8143f489
 multipath-tcp#1 [ffff8808157e77b8] reiserfs_get_block at ffffffffa038ab2d [reiserfs]
 multipath-tcp#2 [ffff8808157e79a8] __block_write_begin at ffffffff8117fb14
 multipath-tcp#3 [ffff8808157e7a98] reiserfs_write_begin at ffffffffa0388695 [reiserfs]
 multipath-tcp#4 [ffff8808157e7ad8] generic_perform_write at ffffffff810ee9e2
 multipath-tcp#5 [ffff8808157e7b58] generic_file_buffered_write at ffffffff810eeb41
 multipath-tcp#6 [ffff8808157e7ba8] __generic_file_aio_write at ffffffff810f1a3a
 multipath-tcp#7 [ffff8808157e7c58] generic_file_aio_write at ffffffff810f1c88
 multipath-tcp#8 [ffff8808157e7cc8] do_sync_write at ffffffff8114f850
 multipath-tcp#9 [ffff8808157e7dd8] do_acct_process at ffffffff810a268f
    [exception RIP: kernel_thread_helper]
    RIP: ffffffff8144a5c0  RSP: ffff8808157e7f58  RFLAGS: 00000202
    RAX: 0000000000000000  RBX: 0000000000000000  RCX: 0000000000000000
    RDX: 0000000000000000  RSI: ffffffff8107af60  RDI: ffff8803ee491d18
    RBP: 0000000000000000   R8: 0000000000000000   R9: 0000000000000000
    R10: 0000000000000000  R11: 0000000000000000  R12: 0000000000000000
    R13: 0000000000000000  R14: 0000000000000000  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018

Signed-off-by: Mike Galbraith <[email protected]>
Signed-off-by: Tejun Heo <[email protected]>
Cc: [email protected]
duncanje pushed a commit to bluca/mptcp that referenced this issue Sep 27, 2013
…/kernel/git/paulg/linux

Paul Gortmaker says:

====================
Changes since v1:
	-get rid of essentially unused variable spotted by
	 Neil Horman (patch multipath-tcp#2)

	-drop patch multipath-tcp#3; defer it for 3.9 content, so Neil,
	 Jon and Ying can discuss its specifics at their
	 leisure while net-next is closed.  (It had no
	 direct dependencies to the rest of the series, and
	 was just an optimization)

	-fix indentation of accept() code directly in place
	 vs. forking it out to a separate function (was patch
	 multipath-tcp#10, now patch multipath-tcp#9).

Rebuilt and re-ran tests just to ensure nothing odd happened.

Original v1 text follows, updated pull information follows that.

           ---------

Here is another batch of TIPC changes.  The most interesting
thing is probably the non-blocking socket connect - I'm told
there were several users looking forward to seeing this.

Also there were some resource limitation changes that had
the right intent back in 2005, but were now apparently causing
needless limitations to people's real use cases; those have
been relaxed/removed.

There is a lockdep splat fix, but no need for a stable backport,
since it is virtually impossible to trigger in mainline; you
have to essentially modify code to force the probabilities
in your favour to see it.

The rest can largely be categorized as general cleanup of things
seen in the process of getting the above changes done.

Tested between 64 and 32 bit nodes with the test suite.  I've
also compile tested all the individual commits on the chain.

I'd originally figured on this queue not being ready for 3.8, but
the extended stabilization window of 3.7 has changed that.  On
the other hand, this can still be 3.9 material, if that simply
works better for folks - no problem for me to defer it to 2013.
If anyone spots any problems then I'll definitely defer it,
rather than rush a last minute respin.
===================

Signed-off-by: David S. Miller <[email protected]>
duncanje pushed a commit to bluca/mptcp that referenced this issue Sep 27, 2013
 This patch supports basic common driver code for LP5521, LP5523/55231 devices.

 ( Driver Structure Data )

 lp55xx_led and lp55xx_chip
 In lp55xx common driver, two different data structure is used.
 o lp55xx_led
   control multi output LED channels such as led current, channel index.
 o lp55xx_chip
   general chip control such like the I2C and platform data.

 For example, LP5521 has maximum 3 LED channels.
 LP5523/55231 has 9 output channels.

 lp55xx_chip for LP5521 ... lp55xx_led multipath-tcp#1
                            lp55xx_led multipath-tcp#2
                            lp55xx_led multipath-tcp#3

 lp55xx_chip for LP5523 ... lp55xx_led multipath-tcp#1
                            lp55xx_led multipath-tcp#2
                            .
                            .
                            lp55xx_led multipath-tcp#9

 ( Platform Data )

 LP5521 and LP5523/55231 have own specific platform data.
 However, this data can be handled with just one platform data structure.
 The lp55xx platform data is declared in the header.
 This structure is derived from leds-lp5521.h and leds-lp5523.h

Signed-off-by: Milo(Woogyom) Kim <[email protected]>
Signed-off-by: Bryan Wu <[email protected]>
duncanje pushed a commit to bluca/mptcp that referenced this issue Sep 27, 2013
i915 driver needs to do modeset when
1. system resumes from sleep
2. lid is opened

In PM_SUSPEND_MEM state, all the GPEs are cleared when system resumes,
thus it is the i915_resume code does the modeset rather than intel_lid_notify().

But in PM_SUSPEND_FREEZE state, this will be broken because
system is still responsive to the lid events.
1. When we close the lid in Freeze state, intel_lid_notify() sets modeset_on_lid.
2. When we reopen the lid, intel_lid_notify() will do a modeset,
   before the system is resumed.
here is the error log,

[92146.548074] WARNING: at drivers/gpu/drm/i915/intel_display.c:1028 intel_wait_for_pipe_off+0x184/0x190 [i915]()
[92146.548076] Hardware name: VGN-Z540N
[92146.548078] pipe_off wait timed out
[92146.548167] Modules linked in: hid_generic usbhid hid snd_hda_codec_realtek snd_hda_intel snd_hda_codec parport_pc snd_hwdep ppdev snd_pcm_oss i915 snd_mixer_oss snd_pcm arc4 iwldvm snd_seq_dummy mac80211 snd_seq_oss snd_seq_midi fbcon tileblit font bitblit softcursor drm_kms_helper snd_rawmidi snd_seq_midi_event coretemp drm snd_seq kvm btusb bluetooth snd_timer iwlwifi pcmcia tpm_infineon i2c_algo_bit joydev snd_seq_device intel_agp cfg80211 snd intel_gtt yenta_socket pcmcia_rsrc sony_laptop agpgart microcode psmouse tpm_tis serio_raw mxm_wmi soundcore snd_page_alloc tpm acpi_cpufreq lpc_ich pcmcia_core tpm_bios mperf processor lp parport firewire_ohci firewire_core crc_itu_t sdhci_pci sdhci thermal e1000e
[92146.548173] Pid: 4304, comm: kworker/0:0 Tainted: G        W    3.8.0-rc3-s0i3-v3-test+ multipath-tcp#9
[92146.548175] Call Trace:
[92146.548189]  [<c10378e2>] warn_slowpath_common+0x72/0xa0
[92146.548227]  [<f86398b4>] ? intel_wait_for_pipe_off+0x184/0x190 [i915]
[92146.548263]  [<f86398b4>] ? intel_wait_for_pipe_off+0x184/0x190 [i915]
[92146.548270]  [<c10379b3>] warn_slowpath_fmt+0x33/0x40
[92146.548307]  [<f86398b4>] intel_wait_for_pipe_off+0x184/0x190 [i915]
[92146.548344]  [<f86399c2>] intel_disable_pipe+0x102/0x190 [i915]
[92146.548380]  [<f8639ea4>] ? intel_disable_plane+0x64/0x80 [i915]
[92146.548417]  [<f8639f7c>] i9xx_crtc_disable+0xbc/0x150 [i915]
[92146.548456]  [<f863ebee>] intel_crtc_update_dpms+0x5e/0x90 [i915]
[92146.548493]  [<f86437cf>] intel_modeset_setup_hw_state+0x42f/0x8f0 [i915]
[92146.548535]  [<f8645b0b>] intel_lid_notify+0x9b/0xc0 [i915]
[92146.548543]  [<c15610d3>] notifier_call_chain+0x43/0x60
[92146.548550]  [<c105d1e1>] __blocking_notifier_call_chain+0x41/0x80
[92146.548556]  [<c105d23f>] blocking_notifier_call_chain+0x1f/0x30
[92146.548563]  [<c131a684>] acpi_lid_send_state+0x78/0xa4
[92146.548569]  [<c131aa9e>] acpi_button_notify+0x3b/0xf1
[92146.548577]  [<c12df56a>] ? acpi_os_execute+0x17/0x19
[92146.548582]  [<c12e591a>] ? acpi_ec_sync_query+0xa5/0xbc
[92146.548589]  [<c12e2b82>] acpi_device_notify+0x16/0x18
[92146.548595]  [<c12f4904>] acpi_ev_notify_dispatch+0x38/0x4f
[92146.548600]  [<c12df0e8>] acpi_os_execute_deferred+0x20/0x2b
[92146.548607]  [<c1051208>] process_one_work+0x128/0x3f0
[92146.548613]  [<c1564f73>] ? common_interrupt+0x33/0x38
[92146.548618]  [<c104f8c0>] ? wake_up_worker+0x30/0x30
[92146.548624]  [<c12df0c8>] ? acpi_os_wait_events_complete+0x1e/0x1e
[92146.548629]  [<c10524f9>] worker_thread+0x119/0x3b0
[92146.548634]  [<c10523e0>] ? manage_workers+0x240/0x240
[92146.548640]  [<c1056e84>] kthread+0x94/0xa0
[92146.548647]  [<c1060000>] ? ftrace_raw_output_sched_stat_runtime+0x70/0xf0
[92146.548652]  [<c15649b7>] ret_from_kernel_thread+0x1b/0x28
[92146.548658]  [<c1056df0>] ? kthread_create_on_node+0xc0/0xc0

three different modeset flags are introduced in this patch
MODESET_ON_LID_OPEN: do modeset on next lid open event
MODESET_DONE:  modeset already done
MODESET_SUSPENDED:  suspended, only do modeset when system is resumed

In this way,
1. when lid is closed, MODESET_ON_LID_OPEN is set so that
   we'll do modeset on next lid open event.
2. when lid is opened, MODESET_DONE is set
   so that duplicate lid open events will be ignored.
3. when system suspends, MODESET_SUSPENDED is set.
   In this case, we will not do modeset on any lid events.

Plus, locking mechanism is also introduced to avoid racing.

Signed-off-by: Zhang Rui <[email protected]>
Signed-off-by: Daniel Vetter <[email protected]>
duncanje pushed a commit to bluca/mptcp that referenced this issue Sep 27, 2013
The following script will produce a kernel oops:

    sudo ip netns add v
    sudo ip netns exec v ip ad add 127.0.0.1/8 dev lo
    sudo ip netns exec v ip link set lo up
    sudo ip netns exec v ip ro add 224.0.0.0/4 dev lo
    sudo ip netns exec v ip li add vxlan0 type vxlan id 42 group 239.1.1.1 dev lo
    sudo ip netns exec v ip link set vxlan0 up
    sudo ip netns del v

where inspect by gdb:

    Program received signal SIGSEGV, Segmentation fault.
    [Switching to Thread 107]
    0xffffffffa0289e33 in ?? ()
    (gdb) bt
    #0  vxlan_leave_group (dev=0xffff88001bafa000) at drivers/net/vxlan.c:533
    multipath-tcp#1  vxlan_stop (dev=0xffff88001bafa000) at drivers/net/vxlan.c:1087
    multipath-tcp#2  0xffffffff812cc498 in __dev_close_many (head=head@entry=0xffff88001f2e7dc8) at net/core/dev.c:1299
    multipath-tcp#3  0xffffffff812cd920 in dev_close_many (head=head@entry=0xffff88001f2e7dc8) at net/core/dev.c:1335
    multipath-tcp#4  0xffffffff812cef31 in rollback_registered_many (head=head@entry=0xffff88001f2e7dc8) at net/core/dev.c:4851
    multipath-tcp#5  0xffffffff812cf040 in unregister_netdevice_many (head=head@entry=0xffff88001f2e7dc8) at net/core/dev.c:5752
    multipath-tcp#6  0xffffffff812cf1ba in default_device_exit_batch (net_list=0xffff88001f2e7e18) at net/core/dev.c:6170
    multipath-tcp#7  0xffffffff812cab27 in cleanup_net (work=<optimized out>) at net/core/net_namespace.c:302
    multipath-tcp#8  0xffffffff810540ef in process_one_work (worker=0xffff88001ba9ed40, work=0xffffffff8167d020) at kernel/workqueue.c:2157
    multipath-tcp#9  0xffffffff810549d0 in worker_thread (__worker=__worker@entry=0xffff88001ba9ed40) at kernel/workqueue.c:2276
    multipath-tcp#10 0xffffffff8105870c in kthread (_create=0xffff88001f2e5d68) at kernel/kthread.c:168
    multipath-tcp#11 <signal handler called>
    multipath-tcp#12 0x0000000000000000 in ?? ()
    multipath-tcp#13 0x0000000000000000 in ?? ()
    (gdb) fr 0
    #0  vxlan_leave_group (dev=0xffff88001bafa000) at drivers/net/vxlan.c:533
    533		struct sock *sk = vn->sock->sk;
    (gdb) l
    528	static int vxlan_leave_group(struct net_device *dev)
    529	{
    530		struct vxlan_dev *vxlan = netdev_priv(dev);
    531		struct vxlan_net *vn = net_generic(dev_net(dev), vxlan_net_id);
    532		int err = 0;
    533		struct sock *sk = vn->sock->sk;
    534		struct ip_mreqn mreq = {
    535			.imr_multiaddr.s_addr	= vxlan->gaddr,
    536			.imr_ifindex		= vxlan->link,
    537		};
    (gdb) p vn->sock
    $4 = (struct socket *) 0x0

The kernel calls `vxlan_exit_net` when deleting the netns before shutting down
vxlan interfaces. Later the removal of all vxlan interfaces, where `vn->sock`
is already gone causes the oops. so we should manually shutdown all interfaces
before deleting `vn->sock` as the patch does.

Signed-off-by: Zang MingJie <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
duncanje pushed a commit to bluca/mptcp that referenced this issue Sep 27, 2013
…behaviors

Both dump_stack() and show_stack() are currently implemented by each
architecture.  show_stack(NULL, NULL) dumps the backtrace for the
current task as does dump_stack().  On some archs, dump_stack() prints
extra information - pid, utsname and so on - in addition to the
backtrace while the two are identical on other archs.

The usages in arch-independent code of the two functions indicate
show_stack(NULL, NULL) should print out bare backtrace while
dump_stack() is used for debugging purposes when something went wrong,
so it does make sense to print additional information on the task which
triggered dump_stack().

There's no reason to require archs to implement two separate but mostly
identical functions.  It leads to unnecessary subtle information.

This patch expands the dummy fallback dump_stack() implementation in
lib/dump_stack.c such that it prints out debug information (taken from
x86) and invokes show_stack(NULL, NULL) and drops arch-specific
dump_stack() implementations in all archs except blackfin.  Blackfin's
dump_stack() does something wonky that I don't understand.

Debug information can be printed separately by calling
dump_stack_print_info() so that arch-specific dump_stack()
implementation can still emit the same debug information.  This is used
in blackfin.

This patch brings the following behavior changes.

* On some archs, an extra level in backtrace for show_stack() could be
  printed.  This is because the top frame was determined in
  dump_stack() on those archs while generic dump_stack() can't do that
  reliably.  It can be compensated by inlining dump_stack() but not
  sure whether that'd be necessary.

* Most archs didn't use to print debug info on dump_stack().  They do
  now.

An example WARN dump follows.

 WARNING: at kernel/workqueue.c:4841 init_workqueues+0x35/0x505()
 Hardware name: empty
 Modules linked in:
 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ multipath-tcp#9
  0000000000000009 ffff88007c861e08 ffffffff81c614dc ffff88007c861e48
  ffffffff8108f50f ffffffff82228240 0000000000000040 ffffffff8234a03c
  0000000000000000 0000000000000000 0000000000000000 ffff88007c861e58
 Call Trace:
  [<ffffffff81c614dc>] dump_stack+0x19/0x1b
  [<ffffffff8108f50f>] warn_slowpath_common+0x7f/0xc0
  [<ffffffff8108f56a>] warn_slowpath_null+0x1a/0x20
  [<ffffffff8234a071>] init_workqueues+0x35/0x505
  ...

v2: CPU number added to the generic debug info as requested by s390
    folks and dropped the s390 specific dump_stack().  This loses %ksp
    from the debug message which the maintainers think isn't important
    enough to keep the s390-specific dump_stack() implementation.

    dump_stack_print_info() is moved to kernel/printk.c from
    lib/dump_stack.c.  Because linkage is per objecct file,
    dump_stack_print_info() living in the same lib file as generic
    dump_stack() means that archs which implement custom dump_stack()
    - at this point, only blackfin - can't use dump_stack_print_info()
    as that will bring in the generic version of dump_stack() too.  v1
    The v1 patch broke build on blackfin due to this issue.  The build
    breakage was reported by Fengguang Wu.

Signed-off-by: Tejun Heo <[email protected]>
Acked-by: David S. Miller <[email protected]>
Acked-by: Vineet Gupta <[email protected]>
Acked-by: Jesper Nilsson <[email protected]>
Acked-by: Vineet Gupta <[email protected]>
Acked-by: Martin Schwidefsky <[email protected]>	[s390 bits]
Cc: Heiko Carstens <[email protected]>
Cc: Mike Frysinger <[email protected]>
Cc: Fengguang Wu <[email protected]>
Cc: Bjorn Helgaas <[email protected]>
Cc: Sam Ravnborg <[email protected]>
Acked-by: Richard Kuo <[email protected]>		[hexagon bits]
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
duncanje pushed a commit to bluca/mptcp that referenced this issue Sep 27, 2013
Daniel Petre reported crashes in icmp_dst_unreach() with following call
graph:

multipath-tcp#3 [ffff88003fc03938] __stack_chk_fail at ffffffff81037f77
multipath-tcp#4 [ffff88003fc03948] icmp_send at ffffffff814d5fec
multipath-tcp#5 [ffff88003fc03ae8] ipv4_link_failure at ffffffff814a1795
multipath-tcp#6 [ffff88003fc03af8] ipgre_tunnel_xmit at ffffffff814e7965
multipath-tcp#7 [ffff88003fc03b78] dev_hard_start_xmit at ffffffff8146e032
multipath-tcp#8 [ffff88003fc03bc8] sch_direct_xmit at ffffffff81487d66
multipath-tcp#9 [ffff88003fc03c08] __qdisc_run at ffffffff81487efd
multipath-tcp#10 [ffff88003fc03c48] dev_queue_xmit at ffffffff8146e5a7
multipath-tcp#11 [ffff88003fc03c88] ip_finish_output at ffffffff814ab596

Daniel found a similar problem mentioned in
 http://lkml.indiana.edu/hypermail/linux/kernel/1007.0/00961.html

And indeed this is the root cause : skb->cb[] contains data fooling IP
stack.

We must clear IPCB in ip_tunnel_xmit() sooner in case dst_link_failure()
is called. Or else skb->cb[] might contain garbage from GSO segmentation
layer.

A similar fix was tested on linux-3.9, but gre code was refactored in
linux-3.10. I'll send patches for stable kernels as well.

Many thanks to Daniel for providing reports, patches and testing !

Reported-by: Daniel Petre <[email protected]>
Signed-off-by: Eric Dumazet <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
duncanje pushed a commit to bluca/mptcp that referenced this issue Sep 27, 2013
Michael L. Semon has been testing CRC patches on a 32 bit system and
been seeing assert failures in the directory code from xfs/080.
Thanks to Michael's heroic efforts with printk debugging, we found
that the problem was that the last free space being left in the
directory structure was too small to fit a unused tag structure and
it was being corrupted and attempting to log a region out of bounds.
Hence the assert failure looked something like:

.....
multipath-tcp#5 calling xfs_dir2_data_log_unused() 36 32
multipath-tcp#1 4092 4095 4096
multipath-tcp#2 8182 8183 4096
XFS: Assertion failed: first <= last && last < BBTOB(bp->b_length), file: fs/xfs/xfs_trans_buf.c, line: 568

Where multipath-tcp#1 showed the first region of the dup being logged (i.e. the
last 4 bytes of a directory buffer) and multipath-tcp#2 shows the corrupt values
being calculated from the length of the dup entry which overflowed
the size of the buffer.

It turns out that the problem was not in the logging code, nor in
the freespace handling code. It is an initial condition bug that
only shows up on 32 bit systems. When a new buffer is initialised,
where's the freespace that is set up:

[  172.316249] calling xfs_dir2_leaf_addname() from xfs_dir_createname()
[  172.316346] multipath-tcp#9 calling xfs_dir2_data_log_unused()
[  172.316351] multipath-tcp#1 calling xfs_trans_log_buf() 60 63 4096
[  172.316353] multipath-tcp#2 calling xfs_trans_log_buf() 4094 4095 4096

Note the offset of the first region being logged? It's 60 bytes into
the buffer. Once I saw that, I pretty much knew that the bug was
going to be caused by this.

Essentially, all direct entries are rounded to 8 bytes in length,
and all entries start with an 8 byte alignment. This means that we
can decode inplace as variables are naturally aligned. With the
directory data supposedly starting on a 8 byte boundary, and all
entries padded to 8 bytes, the minimum freespace in a directory
block is supposed to be 8 bytes, which is large enough to fit a
unused data entry structure (6 bytes in size). The fact we only have
4 bytes of free space indicates a directory data block alignment
problem.

And what do you know - there's an implicit hole in the directory
data block header for the CRC format, which means the header is 60
byte on 32 bit intel systems and 64 bytes on 64 bit systems. Needs
padding. And while looking at the structures, I found the same
problem in the attr leaf header. Fix them both.

Note that this only affects 32 bit systems with CRCs enabled.
Everything else is just fine. Note that CRC enabled filesystems created
before this fix on such systems will not be readable with this fix
applied.

Reported-by: Michael L. Semon <[email protected]>
Debugged-by: Michael L. Semon <[email protected]>
Signed-off-by: Dave Chinner <[email protected]>
Reviewed-by: Ben Myers <[email protected]>
Signed-off-by: Ben Myers <[email protected]>

(cherry picked from commit 8a1fd29)
cpaasch pushed a commit that referenced this issue Sep 30, 2013
commit 8a09a4c upstream.

Commit 1c1d86a ("[media] v4l2: always require v4l2_dev,
rename parent to dev_parent") expects v4l2_dev to be always set.
It converted most of the drivers using the parent field of video_device
to v4l2_dev field. G2D driver did not set the parent field. Hence it got
left out. Without this patch we get the following boot warning and G2D
driver fails to register the video device.
WARNING: CPU: 0 PID: 1 at drivers/media/v4l2-core/v4l2-dev.c:775 __video_register_device+0xfc0/0x1028()
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.11.0-rc1-00001-g1c3e372-dirty #9
[<c0014b7c>] (unwind_backtrace+0x0/0xf4) from [<c0011524>] (show_stack+0x10/0x14)
[<c0011524>] (show_stack+0x10/0x14) from [<c041d7a8>] (dump_stack+0x7c/0xb0)
[<c041d7a8>] (dump_stack+0x7c/0xb0) from [<c001dc94>] (warn_slowpath_common+0x6c/0x88)
[<c001dc94>] (warn_slowpath_common+0x6c/0x88) from [<c001dd4c>] (warn_slowpath_null+0x1c/0x24)
[<c001dd4c>] (warn_slowpath_null+0x1c/0x24) from [<c02cf8d4>] (__video_register_device+0xfc0/0x1028)
[<c02cf8d4>] (__video_register_device+0xfc0/0x1028) from [<c0311a94>] (g2d_probe+0x1f8/0x398)
[<c0311a94>] (g2d_probe+0x1f8/0x398) from [<c0247d54>] (platform_drv_probe+0x14/0x18)
[<c0247d54>] (platform_drv_probe+0x14/0x18) from [<c0246b10>] (driver_probe_device+0x108/0x220)
[<c0246b10>] (driver_probe_device+0x108/0x220) from [<c0246cf8>] (__driver_attach+0x8c/0x90)
[<c0246cf8>] (__driver_attach+0x8c/0x90) from [<c0245050>] (bus_for_each_dev+0x60/0x94)
[<c0245050>] (bus_for_each_dev+0x60/0x94) from [<c02462c8>] (bus_add_driver+0x1c0/0x24c)
[<c02462c8>] (bus_add_driver+0x1c0/0x24c) from [<c02472d0>] (driver_register+0x78/0x140)
[<c02472d0>] (driver_register+0x78/0x140) from [<c00087c8>] (do_one_initcall+0xf8/0x144)
[<c00087c8>] (do_one_initcall+0xf8/0x144) from [<c05b29e8>] (kernel_init_freeable+0x13c/0x1d8)
[<c05b29e8>] (kernel_init_freeable+0x13c/0x1d8) from [<c041a108>] (kernel_init+0xc/0x160)
[<c041a108>] (kernel_init+0xc/0x160) from [<c000e2f8>] (ret_from_fork+0x14/0x3c)
---[ end trace 4e0ec028b0028e02 ]---
s5p-g2d 12800000.g2d: Failed to register video device
s5p-g2d: probe of 12800000.g2d failed with error -22

Signed-off-by: Sachin Kamat <[email protected]>
Cc: Hans Verkuil <[email protected]>
Signed-off-by: Kamil Debski <[email protected]>
Signed-off-by: Mauro Carvalho Chehab <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
cpaasch pushed a commit that referenced this issue Sep 30, 2013
…s struct file

BugLink: http://bugs.launchpad.net/bugs/1221794

commit e4daf1f upstream.

The following call chain:
------------------------------------------------------------
nfs4_get_vfs_file
- nfsd_open
  - dentry_open
    - do_dentry_open
      - __get_file_write_access
        - get_write_access
          - return atomic_inc_unless_negative(&inode->i_writecount) ? 0 : -ETXTBSY;
------------------------------------------------------------

can result in the following state:
------------------------------------------------------------
struct nfs4_file {
...
  fi_fds = {0xffff880c1fa65c80, 0xffffffffffffffe6, 0x0},
  fi_access = {{
      counter = 0x1
    }, {
      counter = 0x0
    }},
...
------------------------------------------------------------

1) First time around, in nfs4_get_vfs_file() fp->fi_fds[O_WRONLY] is
NULL, hence nfsd_open() is called where we get status set to an error
and fp->fi_fds[O_WRONLY] to -ETXTBSY. Thus we do not reach
nfs4_file_get_access() and fi_access[O_WRONLY] is not incremented.

2) Second time around, in nfs4_get_vfs_file() fp->fi_fds[O_WRONLY] is
NOT NULL (-ETXTBSY), so nfsd_open() is NOT called, but
nfs4_file_get_access() IS called and fi_access[O_WRONLY] is incremented.
Thus we leave a landmine in the form of the nfs4_file data structure in
an incorrect state.

3) Eventually, when __nfs4_file_put_access() is called it finds
fi_access[O_WRONLY] being non-zero, it decrements it and calls
nfs4_file_put_fd() which tries to fput -ETXTBSY.
------------------------------------------------------------
...
     [exception RIP: fput+0x9]
     RIP: ffffffff81177fa9  RSP: ffff88062e365c90  RFLAGS: 00010282
     RAX: ffff880c2b3d99cc  RBX: ffff880c2b3d9978  RCX: 0000000000000002
     RDX: dead000000100101  RSI: 0000000000000001  RDI: ffffffffffffffe6
     RBP: ffff88062e365c90   R8: ffff88041fe797d8   R9: ffff88062e365d58
     R10: 0000000000000008  R11: 0000000000000000  R12: 0000000000000001
     R13: 0000000000000007  R14: 0000000000000000  R15: 0000000000000000
     ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
  #9 [ffff88062e365c98] __nfs4_file_put_access at ffffffffa0562334 [nfsd]
 #10 [ffff88062e365cc8] nfs4_file_put_access at ffffffffa05623ab [nfsd]
 #11 [ffff88062e365ce8] free_generic_stateid at ffffffffa056634d [nfsd]
 #12 [ffff88062e365d18] release_open_stateid at ffffffffa0566e4b [nfsd]
 #13 [ffff88062e365d38] nfsd4_close at ffffffffa0567401 [nfsd]
 #14 [ffff88062e365d88] nfsd4_proc_compound at ffffffffa0557f28 [nfsd]
 #15 [ffff88062e365dd8] nfsd_dispatch at ffffffffa054543e [nfsd]
 #16 [ffff88062e365e18] svc_process_common at ffffffffa04ba5a4 [sunrpc]
 #17 [ffff88062e365e98] svc_process at ffffffffa04babe0 [sunrpc]
 #18 [ffff88062e365eb8] nfsd at ffffffffa0545b62 [nfsd]
 #19 [ffff88062e365ee8] kthread at ffffffff81090886
 #20 [ffff88062e365f48] kernel_thread at ffffffff8100c14a
------------------------------------------------------------

Signed-off-by: Harshula Jayasuriya <[email protected]>
Signed-off-by: J. Bruce Fields <[email protected]>
Signed-off-by: Kamal Mostafa <[email protected]>
Signed-off-by: Brad Figg <[email protected]>
cpaasch pushed a commit that referenced this issue Sep 30, 2013
BugLink: http://bugs.launchpad.net/bugs/1221794

commit ea3768b upstream.

We used to keep the port's char device structs and the /sys entries
around till the last reference to the port was dropped.  This is
actually unnecessary, and resulted in buggy behaviour:

1. Open port in guest
2. Hot-unplug port
3. Hot-plug a port with the same 'name' property as the unplugged one

This resulted in hot-plug being unsuccessful, as a port with the same
name already exists (even though it was unplugged).

This behaviour resulted in a warning message like this one:

-------------------8<---------------------------------------
WARNING: at fs/sysfs/dir.c:512 sysfs_add_one+0xc9/0x130() (Not tainted)
Hardware name: KVM
sysfs: cannot create duplicate filename
'/devices/pci0000:00/0000:00:04.0/virtio0/virtio-ports/vport0p1'

Call Trace:
 [<ffffffff8106b607>] ? warn_slowpath_common+0x87/0xc0
 [<ffffffff8106b6f6>] ? warn_slowpath_fmt+0x46/0x50
 [<ffffffff811f2319>] ? sysfs_add_one+0xc9/0x130
 [<ffffffff811f23e8>] ? create_dir+0x68/0xb0
 [<ffffffff811f2469>] ? sysfs_create_dir+0x39/0x50
 [<ffffffff81273129>] ? kobject_add_internal+0xb9/0x260
 [<ffffffff812733d8>] ? kobject_add_varg+0x38/0x60
 [<ffffffff812734b4>] ? kobject_add+0x44/0x70
 [<ffffffff81349de4>] ? get_device_parent+0xf4/0x1d0
 [<ffffffff8134b389>] ? device_add+0xc9/0x650

-------------------8<---------------------------------------

Instead of relying on guest applications to release all references to
the ports, we should go ahead and unregister the port from all the core
layers.  Any open/read calls on the port will then just return errors,
and an unplug/plug operation on the host will succeed as expected.

This also caused buggy behaviour in case of the device removal (not just
a port): when the device was removed (which means all ports on that
device are removed automatically as well), the ports with active
users would clean up only when the last references were dropped -- and
it would be too late then to be referencing char device pointers,
resulting in oopses:

-------------------8<---------------------------------------
PID: 6162   TASK: ffff8801147ad500  CPU: 0   COMMAND: "cat"
 #0 [ffff88011b9d5a90] machine_kexec at ffffffff8103232b
 #1 [ffff88011b9d5af0] crash_kexec at ffffffff810b9322
 #2 [ffff88011b9d5bc0] oops_end at ffffffff814f4a50
 #3 [ffff88011b9d5bf0] die at ffffffff8100f26b
 #4 [ffff88011b9d5c20] do_general_protection at ffffffff814f45e2
 #5 [ffff88011b9d5c50] general_protection at ffffffff814f3db5
    [exception RIP: strlen+2]
    RIP: ffffffff81272ae2  RSP: ffff88011b9d5d00  RFLAGS: 00010246
    RAX: 0000000000000000  RBX: ffff880118901c18  RCX: 0000000000000000
    RDX: ffff88011799982c  RSI: 00000000000000d0  RDI: 3a303030302f3030
    RBP: ffff88011b9d5d38   R8: 0000000000000006   R9: ffffffffa0134500
    R10: 0000000000001000  R11: 0000000000001000  R12: ffff880117a1cc10
    R13: 00000000000000d0  R14: 0000000000000017  R15: ffffffff81aff700
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #6 [ffff88011b9d5d00] kobject_get_path at ffffffff8126dc5d
 #7 [ffff88011b9d5d40] kobject_uevent_env at ffffffff8126e551
 #8 [ffff88011b9d5dd0] kobject_uevent at ffffffff8126e9eb
 #9 [ffff88011b9d5de0] device_del at ffffffff813440c7

-------------------8<---------------------------------------

So clean up when we have all the context, and all that's left to do when
the references to the port have dropped is to free up the port struct
itself.

Reported-by: chayang <[email protected]>
Reported-by: YOGANANTH SUBRAMANIAN <[email protected]>
Reported-by: FuXiangChun <[email protected]>
Reported-by: Qunfang Zhang <[email protected]>
Reported-by: Sibiao Luo <[email protected]>
Signed-off-by: Amit Shah <[email protected]>
Signed-off-by: Rusty Russell <[email protected]>
Signed-off-by: Kamal Mostafa <[email protected]>
Signed-off-by: Brad Figg <[email protected]>
cpaasch pushed a commit that referenced this issue Oct 18, 2013
BugLink: http://bugs.launchpad.net/bugs/1233227

commit 8a09a4c upstream.

Commit 1c1d86a ("[media] v4l2: always require v4l2_dev,
rename parent to dev_parent") expects v4l2_dev to be always set.
It converted most of the drivers using the parent field of video_device
to v4l2_dev field. G2D driver did not set the parent field. Hence it got
left out. Without this patch we get the following boot warning and G2D
driver fails to register the video device.
WARNING: CPU: 0 PID: 1 at drivers/media/v4l2-core/v4l2-dev.c:775 __video_register_device+0xfc0/0x1028()
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.11.0-rc1-00001-g1c3e372-dirty #9
[<c0014b7c>] (unwind_backtrace+0x0/0xf4) from [<c0011524>] (show_stack+0x10/0x14)
[<c0011524>] (show_stack+0x10/0x14) from [<c041d7a8>] (dump_stack+0x7c/0xb0)
[<c041d7a8>] (dump_stack+0x7c/0xb0) from [<c001dc94>] (warn_slowpath_common+0x6c/0x88)
[<c001dc94>] (warn_slowpath_common+0x6c/0x88) from [<c001dd4c>] (warn_slowpath_null+0x1c/0x24)
[<c001dd4c>] (warn_slowpath_null+0x1c/0x24) from [<c02cf8d4>] (__video_register_device+0xfc0/0x1028)
[<c02cf8d4>] (__video_register_device+0xfc0/0x1028) from [<c0311a94>] (g2d_probe+0x1f8/0x398)
[<c0311a94>] (g2d_probe+0x1f8/0x398) from [<c0247d54>] (platform_drv_probe+0x14/0x18)
[<c0247d54>] (platform_drv_probe+0x14/0x18) from [<c0246b10>] (driver_probe_device+0x108/0x220)
[<c0246b10>] (driver_probe_device+0x108/0x220) from [<c0246cf8>] (__driver_attach+0x8c/0x90)
[<c0246cf8>] (__driver_attach+0x8c/0x90) from [<c0245050>] (bus_for_each_dev+0x60/0x94)
[<c0245050>] (bus_for_each_dev+0x60/0x94) from [<c02462c8>] (bus_add_driver+0x1c0/0x24c)
[<c02462c8>] (bus_add_driver+0x1c0/0x24c) from [<c02472d0>] (driver_register+0x78/0x140)
[<c02472d0>] (driver_register+0x78/0x140) from [<c00087c8>] (do_one_initcall+0xf8/0x144)
[<c00087c8>] (do_one_initcall+0xf8/0x144) from [<c05b29e8>] (kernel_init_freeable+0x13c/0x1d8)
[<c05b29e8>] (kernel_init_freeable+0x13c/0x1d8) from [<c041a108>] (kernel_init+0xc/0x160)
[<c041a108>] (kernel_init+0xc/0x160) from [<c000e2f8>] (ret_from_fork+0x14/0x3c)
---[ end trace 4e0ec028b0028e02 ]---
s5p-g2d 12800000.g2d: Failed to register video device
s5p-g2d: probe of 12800000.g2d failed with error -22

Signed-off-by: Sachin Kamat <[email protected]>
Cc: Hans Verkuil <[email protected]>
Signed-off-by: Kamil Debski <[email protected]>
Signed-off-by: Mauro Carvalho Chehab <[email protected]>
Signed-off-by: Kamal Mostafa <[email protected]>
Signed-off-by: Steve Conklin <[email protected]>
cpaasch pushed a commit that referenced this issue Oct 27, 2013
Commit 1c1d86a ("[media] v4l2: always require v4l2_dev,
rename parent to dev_parent") expects v4l2_dev to be always set.
It converted most of the drivers using the parent field of video_device
to v4l2_dev field. G2D driver did not set the parent field. Hence it got
left out. Without this patch we get the following boot warning and G2D
driver fails to register the video device.
WARNING: CPU: 0 PID: 1 at drivers/media/v4l2-core/v4l2-dev.c:775 __video_register_device+0xfc0/0x1028()
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.11.0-rc1-00001-g1c3e372-dirty #9
[<c0014b7c>] (unwind_backtrace+0x0/0xf4) from [<c0011524>] (show_stack+0x10/0x14)
[<c0011524>] (show_stack+0x10/0x14) from [<c041d7a8>] (dump_stack+0x7c/0xb0)
[<c041d7a8>] (dump_stack+0x7c/0xb0) from [<c001dc94>] (warn_slowpath_common+0x6c/0x88)
[<c001dc94>] (warn_slowpath_common+0x6c/0x88) from [<c001dd4c>] (warn_slowpath_null+0x1c/0x24)
[<c001dd4c>] (warn_slowpath_null+0x1c/0x24) from [<c02cf8d4>] (__video_register_device+0xfc0/0x1028)
[<c02cf8d4>] (__video_register_device+0xfc0/0x1028) from [<c0311a94>] (g2d_probe+0x1f8/0x398)
[<c0311a94>] (g2d_probe+0x1f8/0x398) from [<c0247d54>] (platform_drv_probe+0x14/0x18)
[<c0247d54>] (platform_drv_probe+0x14/0x18) from [<c0246b10>] (driver_probe_device+0x108/0x220)
[<c0246b10>] (driver_probe_device+0x108/0x220) from [<c0246cf8>] (__driver_attach+0x8c/0x90)
[<c0246cf8>] (__driver_attach+0x8c/0x90) from [<c0245050>] (bus_for_each_dev+0x60/0x94)
[<c0245050>] (bus_for_each_dev+0x60/0x94) from [<c02462c8>] (bus_add_driver+0x1c0/0x24c)
[<c02462c8>] (bus_add_driver+0x1c0/0x24c) from [<c02472d0>] (driver_register+0x78/0x140)
[<c02472d0>] (driver_register+0x78/0x140) from [<c00087c8>] (do_one_initcall+0xf8/0x144)
[<c00087c8>] (do_one_initcall+0xf8/0x144) from [<c05b29e8>] (kernel_init_freeable+0x13c/0x1d8)
[<c05b29e8>] (kernel_init_freeable+0x13c/0x1d8) from [<c041a108>] (kernel_init+0xc/0x160)
[<c041a108>] (kernel_init+0xc/0x160) from [<c000e2f8>] (ret_from_fork+0x14/0x3c)
---[ end trace 4e0ec028b0028e02 ]---
s5p-g2d 12800000.g2d: Failed to register video device
s5p-g2d: probe of 12800000.g2d failed with error -22

Signed-off-by: Sachin Kamat <[email protected]>
Cc: Hans Verkuil <[email protected]>
Signed-off-by: Kamil Debski <[email protected]>
Signed-off-by: Mauro Carvalho Chehab <[email protected]>
cpaasch pushed a commit that referenced this issue Oct 27, 2013
We used to keep the port's char device structs and the /sys entries
around till the last reference to the port was dropped.  This is
actually unnecessary, and resulted in buggy behaviour:

1. Open port in guest
2. Hot-unplug port
3. Hot-plug a port with the same 'name' property as the unplugged one

This resulted in hot-plug being unsuccessful, as a port with the same
name already exists (even though it was unplugged).

This behaviour resulted in a warning message like this one:

-------------------8<---------------------------------------
WARNING: at fs/sysfs/dir.c:512 sysfs_add_one+0xc9/0x130() (Not tainted)
Hardware name: KVM
sysfs: cannot create duplicate filename
'/devices/pci0000:00/0000:00:04.0/virtio0/virtio-ports/vport0p1'

Call Trace:
 [<ffffffff8106b607>] ? warn_slowpath_common+0x87/0xc0
 [<ffffffff8106b6f6>] ? warn_slowpath_fmt+0x46/0x50
 [<ffffffff811f2319>] ? sysfs_add_one+0xc9/0x130
 [<ffffffff811f23e8>] ? create_dir+0x68/0xb0
 [<ffffffff811f2469>] ? sysfs_create_dir+0x39/0x50
 [<ffffffff81273129>] ? kobject_add_internal+0xb9/0x260
 [<ffffffff812733d8>] ? kobject_add_varg+0x38/0x60
 [<ffffffff812734b4>] ? kobject_add+0x44/0x70
 [<ffffffff81349de4>] ? get_device_parent+0xf4/0x1d0
 [<ffffffff8134b389>] ? device_add+0xc9/0x650

-------------------8<---------------------------------------

Instead of relying on guest applications to release all references to
the ports, we should go ahead and unregister the port from all the core
layers.  Any open/read calls on the port will then just return errors,
and an unplug/plug operation on the host will succeed as expected.

This also caused buggy behaviour in case of the device removal (not just
a port): when the device was removed (which means all ports on that
device are removed automatically as well), the ports with active
users would clean up only when the last references were dropped -- and
it would be too late then to be referencing char device pointers,
resulting in oopses:

-------------------8<---------------------------------------
PID: 6162   TASK: ffff8801147ad500  CPU: 0   COMMAND: "cat"
 #0 [ffff88011b9d5a90] machine_kexec at ffffffff8103232b
 #1 [ffff88011b9d5af0] crash_kexec at ffffffff810b9322
 #2 [ffff88011b9d5bc0] oops_end at ffffffff814f4a50
 #3 [ffff88011b9d5bf0] die at ffffffff8100f26b
 #4 [ffff88011b9d5c20] do_general_protection at ffffffff814f45e2
 #5 [ffff88011b9d5c50] general_protection at ffffffff814f3db5
    [exception RIP: strlen+2]
    RIP: ffffffff81272ae2  RSP: ffff88011b9d5d00  RFLAGS: 00010246
    RAX: 0000000000000000  RBX: ffff880118901c18  RCX: 0000000000000000
    RDX: ffff88011799982c  RSI: 00000000000000d0  RDI: 3a303030302f3030
    RBP: ffff88011b9d5d38   R8: 0000000000000006   R9: ffffffffa0134500
    R10: 0000000000001000  R11: 0000000000001000  R12: ffff880117a1cc10
    R13: 00000000000000d0  R14: 0000000000000017  R15: ffffffff81aff700
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #6 [ffff88011b9d5d00] kobject_get_path at ffffffff8126dc5d
 #7 [ffff88011b9d5d40] kobject_uevent_env at ffffffff8126e551
 #8 [ffff88011b9d5dd0] kobject_uevent at ffffffff8126e9eb
 #9 [ffff88011b9d5de0] device_del at ffffffff813440c7

-------------------8<---------------------------------------

So clean up when we have all the context, and all that's left to do when
the references to the port have dropped is to free up the port struct
itself.

CC: <[email protected]>
Reported-by: chayang <[email protected]>
Reported-by: YOGANANTH SUBRAMANIAN <[email protected]>
Reported-by: FuXiangChun <[email protected]>
Reported-by: Qunfang Zhang <[email protected]>
Reported-by: Sibiao Luo <[email protected]>
Signed-off-by: Amit Shah <[email protected]>
Signed-off-by: Rusty Russell <[email protected]>
cpaasch pushed a commit that referenced this issue Oct 27, 2013
Dave has reported the following lockdep splat:

  =================================
  [ INFO: inconsistent lock state ]
  3.11.0-rc1+ #9 Not tainted
  ---------------------------------
  inconsistent {RECLAIM_FS-ON-W} -> {IN-RECLAIM_FS-W} usage.
  kswapd0/49 [HC0[0]:SC0[0]:HE1:SE1] takes:
   (&mapping->i_mmap_mutex){+.+.?.}, at: [<c114971b>] page_referenced+0x87/0x5e3
  {RECLAIM_FS-ON-W} state was registered at:
     mark_held_locks+0x81/0xe7
     lockdep_trace_alloc+0x5e/0xbc
     __alloc_pages_nodemask+0x8b/0x9b6
     __get_free_pages+0x20/0x31
     get_zeroed_page+0x12/0x14
     __pmd_alloc+0x1c/0x6b
     huge_pmd_share+0x265/0x283
     huge_pte_alloc+0x5d/0x71
     hugetlb_fault+0x7c/0x64a
     handle_mm_fault+0x255/0x299
     __do_page_fault+0x142/0x55c
     do_page_fault+0xd/0x16
     error_code+0x6c/0x74
  irq event stamp: 3136917
  hardirqs last  enabled at (3136917):  _raw_spin_unlock_irq+0x27/0x50
  hardirqs last disabled at (3136916):  _raw_spin_lock_irq+0x15/0x78
  softirqs last  enabled at (3136180):  __do_softirq+0x137/0x30f
  softirqs last disabled at (3136175):  irq_exit+0xa8/0xaa
  other info that might help us debug this:
   Possible unsafe locking scenario:
         CPU0
         ----
    lock(&mapping->i_mmap_mutex);
    <Interrupt>
      lock(&mapping->i_mmap_mutex);

  *** DEADLOCK ***
  no locks held by kswapd0/49.

  stack backtrace:
  CPU: 1 PID: 49 Comm: kswapd0 Not tainted 3.11.0-rc1+ #9
  Hardware name: Dell Inc.                 Precision WorkStation 490    /0DT031, BIOS A08 04/25/2008
  Call Trace:
    dump_stack+0x4b/0x79
    print_usage_bug+0x1d9/0x1e3
    mark_lock+0x1e0/0x261
    __lock_acquire+0x623/0x17f2
    lock_acquire+0x7d/0x195
    mutex_lock_nested+0x6c/0x3a7
    page_referenced+0x87/0x5e3
    shrink_page_list+0x3d9/0x947
    shrink_inactive_list+0x155/0x4cb
    shrink_lruvec+0x300/0x5ce
    shrink_zone+0x53/0x14e
    kswapd+0x517/0xa75
    kthread+0xa8/0xaa
    ret_from_kernel_thread+0x1b/0x28

which is a false positive caused by hugetlb pmd sharing code which
allocates a new pmd from withing mapping->i_mmap_mutex.  If this
allocation causes reclaim then the lockdep detector complains that we
might self-deadlock.

This is not correct though, because hugetlb pages are not reclaimable so
their mapping will be never touched from the reclaim path.

The patch tells lockup detector that hugetlb i_mmap_mutex is special by
assigning it a separate lockdep class so it won't report possible
deadlocks on unrelated mappings.

[[email protected]: comment for annotation]
Reported-by: Dave Jones <[email protected]>
Signed-off-by: Michal Hocko <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Reviewed-by: Minchan Kim <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
cpaasch pushed a commit that referenced this issue Oct 28, 2013
BugLink: http://bugs.launchpad.net/bugs/1242700

commit 6c00350 upstream.

Some ARC SMP systems lack native atomic R-M-W (LLOCK/SCOND) insns and
can only use atomic EX insn (reg with mem) to build higher level R-M-W
primitives. This includes a SystemC based SMP simulation model.

So rwlocks need to use a protecting spinlock for atomic cmp-n-exchange
operation to update reader(s)/writer count.

The spinlock operation itself looks as follows:

	mov reg, 1		; 1=locked, 0=unlocked
retry:
	EX reg, [lock]		; load existing, store 1, atomically
	BREQ reg, 1, rety	; if already locked, retry

In single-threaded simulation, SystemC alternates between the 2 cores
with "N" insn each based scheduling. Additionally for insn with global
side effect, such as EX writing to shared mem, a core switch is
enforced too.

Given that, 2 cores doing a repeated EX on same location, Linux often
got into a livelock e.g. when both cores were fiddling with tasklist
lock (gdbserver / hackbench) for read/write respectively as the
sequence diagram below shows:

           core1                                   core2
         --------                                --------
1. spin lock [EX r=0, w=1] - LOCKED
2. rwlock(Read)            - LOCKED
3. spin unlock  [ST 0]     - UNLOCKED
                                         spin lock [EX r=0,w=1] - LOCKED
                      -- resched core 1----

5. spin lock [EX r=1] - ALREADY-LOCKED

                      -- resched core 2----
6.                                       rwlock(Write) - READER-LOCKED
7.                                       spin unlock [ST 0]
8.                                       rwlock failed, retry again

9.                                       spin lock  [EX r=0, w=1]
                      -- resched core 1----

10  spinlock locked in #9, retry #5
11. spin lock [EX gets 1]
                      -- resched core 2----
...
...

The fix was to unlock using the EX insn too (step 7), to trigger another
SystemC scheduling pass which would let core1 proceed, eliding the
livelock.

Signed-off-by: Vineet Gupta <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Brad Figg <[email protected]>
cpaasch pushed a commit that referenced this issue Oct 28, 2013
commit 6c00350 upstream.

Some ARC SMP systems lack native atomic R-M-W (LLOCK/SCOND) insns and
can only use atomic EX insn (reg with mem) to build higher level R-M-W
primitives. This includes a SystemC based SMP simulation model.

So rwlocks need to use a protecting spinlock for atomic cmp-n-exchange
operation to update reader(s)/writer count.

The spinlock operation itself looks as follows:

	mov reg, 1		; 1=locked, 0=unlocked
retry:
	EX reg, [lock]		; load existing, store 1, atomically
	BREQ reg, 1, rety	; if already locked, retry

In single-threaded simulation, SystemC alternates between the 2 cores
with "N" insn each based scheduling. Additionally for insn with global
side effect, such as EX writing to shared mem, a core switch is
enforced too.

Given that, 2 cores doing a repeated EX on same location, Linux often
got into a livelock e.g. when both cores were fiddling with tasklist
lock (gdbserver / hackbench) for read/write respectively as the
sequence diagram below shows:

           core1                                   core2
         --------                                --------
1. spin lock [EX r=0, w=1] - LOCKED
2. rwlock(Read)            - LOCKED
3. spin unlock  [ST 0]     - UNLOCKED
                                         spin lock [EX r=0,w=1] - LOCKED
                      -- resched core 1----

5. spin lock [EX r=1] - ALREADY-LOCKED

                      -- resched core 2----
6.                                       rwlock(Write) - READER-LOCKED
7.                                       spin unlock [ST 0]
8.                                       rwlock failed, retry again

9.                                       spin lock  [EX r=0, w=1]
                      -- resched core 1----

10  spinlock locked in #9, retry #5
11. spin lock [EX gets 1]
                      -- resched core 2----
...
...

The fix was to unlock using the EX insn too (step 7), to trigger another
SystemC scheduling pass which would let core1 proceed, eliding the
livelock.

Signed-off-by: Vineet Gupta <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
cpaasch pushed a commit that referenced this issue Nov 7, 2013
commit 6c00350 upstream.

Some ARC SMP systems lack native atomic R-M-W (LLOCK/SCOND) insns and
can only use atomic EX insn (reg with mem) to build higher level R-M-W
primitives. This includes a SystemC based SMP simulation model.

So rwlocks need to use a protecting spinlock for atomic cmp-n-exchange
operation to update reader(s)/writer count.

The spinlock operation itself looks as follows:

	mov reg, 1		; 1=locked, 0=unlocked
retry:
	EX reg, [lock]		; load existing, store 1, atomically
	BREQ reg, 1, rety	; if already locked, retry

In single-threaded simulation, SystemC alternates between the 2 cores
with "N" insn each based scheduling. Additionally for insn with global
side effect, such as EX writing to shared mem, a core switch is
enforced too.

Given that, 2 cores doing a repeated EX on same location, Linux often
got into a livelock e.g. when both cores were fiddling with tasklist
lock (gdbserver / hackbench) for read/write respectively as the
sequence diagram below shows:

           core1                                   core2
         --------                                --------
1. spin lock [EX r=0, w=1] - LOCKED
2. rwlock(Read)            - LOCKED
3. spin unlock  [ST 0]     - UNLOCKED
                                         spin lock [EX r=0,w=1] - LOCKED
                      -- resched core 1----

5. spin lock [EX r=1] - ALREADY-LOCKED

                      -- resched core 2----
6.                                       rwlock(Write) - READER-LOCKED
7.                                       spin unlock [ST 0]
8.                                       rwlock failed, retry again

9.                                       spin lock  [EX r=0, w=1]
                      -- resched core 1----

10  spinlock locked in #9, retry #5
11. spin lock [EX gets 1]
                      -- resched core 2----
...
...

The fix was to unlock using the EX insn too (step 7), to trigger another
SystemC scheduling pass which would let core1 proceed, eliding the
livelock.

Signed-off-by: Vineet Gupta <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
cpaasch pushed a commit that referenced this issue Dec 4, 2013
commit 057db84 upstream.

Andrey reported the following report:

ERROR: AddressSanitizer: heap-buffer-overflow on address ffff8800359c99f3
ffff8800359c99f3 is located 0 bytes to the right of 243-byte region [ffff8800359c9900, ffff8800359c99f3)
Accessed by thread T13003:
  #0 ffffffff810dd2da (asan_report_error+0x32a/0x440)
  #1 ffffffff810dc6b0 (asan_check_region+0x30/0x40)
  #2 ffffffff810dd4d3 (__tsan_write1+0x13/0x20)
  #3 ffffffff811cd19e (ftrace_regex_release+0x1be/0x260)
  #4 ffffffff812a1065 (__fput+0x155/0x360)
  #5 ffffffff812a12de (____fput+0x1e/0x30)
  #6 ffffffff8111708d (task_work_run+0x10d/0x140)
  #7 ffffffff810ea043 (do_exit+0x433/0x11f0)
  #8 ffffffff810eaee4 (do_group_exit+0x84/0x130)
  #9 ffffffff810eafb1 (SyS_exit_group+0x21/0x30)
  #10 ffffffff81928782 (system_call_fastpath+0x16/0x1b)

Allocated by thread T5167:
  #0 ffffffff810dc778 (asan_slab_alloc+0x48/0xc0)
  #1 ffffffff8128337c (__kmalloc+0xbc/0x500)
  #2 ffffffff811d9d54 (trace_parser_get_init+0x34/0x90)
  #3 ffffffff811cd7b3 (ftrace_regex_open+0x83/0x2e0)
  #4 ffffffff811cda7d (ftrace_filter_open+0x2d/0x40)
  #5 ffffffff8129b4ff (do_dentry_open+0x32f/0x430)
  #6 ffffffff8129b668 (finish_open+0x68/0xa0)
  #7 ffffffff812b66ac (do_last+0xb8c/0x1710)
  #8 ffffffff812b7350 (path_openat+0x120/0xb50)
  #9 ffffffff812b8884 (do_filp_open+0x54/0xb0)
  #10 ffffffff8129d36c (do_sys_open+0x1ac/0x2c0)
  #11 ffffffff8129d4b7 (SyS_open+0x37/0x50)
  #12 ffffffff81928782 (system_call_fastpath+0x16/0x1b)

Shadow bytes around the buggy address:
  ffff8800359c9700: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  ffff8800359c9780: fd fd fd fd fd fd fd fd fa fa fa fa fa fa fa fa
  ffff8800359c9800: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  ffff8800359c9880: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  ffff8800359c9900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
=>ffff8800359c9980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00[03]fb
  ffff8800359c9a00: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  ffff8800359c9a80: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  ffff8800359c9b00: fa fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00
  ffff8800359c9b80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  ffff8800359c9c00: 00 00 00 00 00 00 00 00 fa fa fa fa fa fa fa fa
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07
  Heap redzone:          fa
  Heap kmalloc redzone:  fb
  Freed heap region:     fd
  Shadow gap:            fe

The out-of-bounds access happens on 'parser->buffer[parser->idx] = 0;'

Although the crash happened in ftrace_regex_open() the real bug
occurred in trace_get_user() where there's an incrementation to
parser->idx without a check against the size. The way it is triggered
is if userspace sends in 128 characters (EVENT_BUF_SIZE + 1), the loop
that reads the last character stores it and then breaks out because
there is no more characters. Then the last character is read to determine
what to do next, and the index is incremented without checking size.

Then the caller of trace_get_user() usually nulls out the last character
with a zero, but since the index is equal to the size, it writes a nul
character after the allocated space, which can corrupt memory.

Luckily, only root user has write access to this file.

Link: http://lkml.kernel.org/r/[email protected]

Reported-by: Andrey Konovalov <[email protected]>
Signed-off-by: Steven Rostedt <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
cpaasch pushed a commit that referenced this issue Dec 4, 2013
BugLink: http://bugs.launchpad.net/bugs/1257037

commit 057db84 upstream.

Andrey reported the following report:

ERROR: AddressSanitizer: heap-buffer-overflow on address ffff8800359c99f3
ffff8800359c99f3 is located 0 bytes to the right of 243-byte region [ffff8800359c9900, ffff8800359c99f3)
Accessed by thread T13003:
  #0 ffffffff810dd2da (asan_report_error+0x32a/0x440)
  #1 ffffffff810dc6b0 (asan_check_region+0x30/0x40)
  #2 ffffffff810dd4d3 (__tsan_write1+0x13/0x20)
  #3 ffffffff811cd19e (ftrace_regex_release+0x1be/0x260)
  #4 ffffffff812a1065 (__fput+0x155/0x360)
  #5 ffffffff812a12de (____fput+0x1e/0x30)
  #6 ffffffff8111708d (task_work_run+0x10d/0x140)
  #7 ffffffff810ea043 (do_exit+0x433/0x11f0)
  #8 ffffffff810eaee4 (do_group_exit+0x84/0x130)
  #9 ffffffff810eafb1 (SyS_exit_group+0x21/0x30)
  #10 ffffffff81928782 (system_call_fastpath+0x16/0x1b)

Allocated by thread T5167:
  #0 ffffffff810dc778 (asan_slab_alloc+0x48/0xc0)
  #1 ffffffff8128337c (__kmalloc+0xbc/0x500)
  #2 ffffffff811d9d54 (trace_parser_get_init+0x34/0x90)
  #3 ffffffff811cd7b3 (ftrace_regex_open+0x83/0x2e0)
  #4 ffffffff811cda7d (ftrace_filter_open+0x2d/0x40)
  #5 ffffffff8129b4ff (do_dentry_open+0x32f/0x430)
  #6 ffffffff8129b668 (finish_open+0x68/0xa0)
  #7 ffffffff812b66ac (do_last+0xb8c/0x1710)
  #8 ffffffff812b7350 (path_openat+0x120/0xb50)
  #9 ffffffff812b8884 (do_filp_open+0x54/0xb0)
  #10 ffffffff8129d36c (do_sys_open+0x1ac/0x2c0)
  #11 ffffffff8129d4b7 (SyS_open+0x37/0x50)
  #12 ffffffff81928782 (system_call_fastpath+0x16/0x1b)

Shadow bytes around the buggy address:
  ffff8800359c9700: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  ffff8800359c9780: fd fd fd fd fd fd fd fd fa fa fa fa fa fa fa fa
  ffff8800359c9800: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  ffff8800359c9880: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  ffff8800359c9900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
=>ffff8800359c9980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00[03]fb
  ffff8800359c9a00: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  ffff8800359c9a80: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  ffff8800359c9b00: fa fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00
  ffff8800359c9b80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  ffff8800359c9c00: 00 00 00 00 00 00 00 00 fa fa fa fa fa fa fa fa
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07
  Heap redzone:          fa
  Heap kmalloc redzone:  fb
  Freed heap region:     fd
  Shadow gap:            fe

The out-of-bounds access happens on 'parser->buffer[parser->idx] = 0;'

Although the crash happened in ftrace_regex_open() the real bug
occurred in trace_get_user() where there's an incrementation to
parser->idx without a check against the size. The way it is triggered
is if userspace sends in 128 characters (EVENT_BUF_SIZE + 1), the loop
that reads the last character stores it and then breaks out because
there is no more characters. Then the last character is read to determine
what to do next, and the index is incremented without checking size.

Then the caller of trace_get_user() usually nulls out the last character
with a zero, but since the index is equal to the size, it writes a nul
character after the allocated space, which can corrupt memory.

Luckily, only root user has write access to this file.

Link: http://lkml.kernel.org/r/[email protected]

Reported-by: Andrey Konovalov <[email protected]>
Signed-off-by: Steven Rostedt <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Brad Figg <[email protected]>
cpaasch pushed a commit that referenced this issue Jan 22, 2014
BugLink: http://bugs.launchpad.net/bugs/1269863

commit f873042 upstream.

 bridge dev

When the following commands are executed:

brctl addbr br0
ifconfig br0 hw ether <addr>
rmmod bridge

The calltrace will occur:

[  563.312114] device eth1 left promiscuous mode
[  563.312188] br0: port 1(eth1) entered disabled state
[  563.468190] kmem_cache_destroy bridge_fdb_cache: Slab cache still has objects
[  563.468197] CPU: 6 PID: 6982 Comm: rmmod Tainted: G           O 3.12.0-0.7-default+ #9
[  563.468199] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007
[  563.468200]  0000000000000880 ffff88010f111e98 ffffffff814d1c92 ffff88010f111eb8
[  563.468204]  ffffffff81148efd ffff88010f111eb8 0000000000000000 ffff88010f111ec8
[  563.468206]  ffffffffa062a270 ffff88010f111ed8 ffffffffa063ac76 ffff88010f111f78
[  563.468209] Call Trace:
[  563.468218]  [<ffffffff814d1c92>] dump_stack+0x6a/0x78
[  563.468234]  [<ffffffff81148efd>] kmem_cache_destroy+0xfd/0x100
[  563.468242]  [<ffffffffa062a270>] br_fdb_fini+0x10/0x20 [bridge]
[  563.468247]  [<ffffffffa063ac76>] br_deinit+0x4e/0x50 [bridge]
[  563.468254]  [<ffffffff810c7dc9>] SyS_delete_module+0x199/0x2b0
[  563.468259]  [<ffffffff814e0922>] system_call_fastpath+0x16/0x1b
[  570.377958] Bridge firewalling registered

--------------------------- cut here -------------------------------

The reason is that when the bridge dev's address is changed, the
br_fdb_change_mac_address() will add new address in fdb, but when
the bridge was removed, the address entry in the fdb did not free,
the bridge_fdb_cache still has objects when destroy the cache, Fix
this by flushing the bridge address entry when removing the bridge.

v2: according to the Toshiaki Makita and Vlad's suggestion, I only
    delete the vlan0 entry, it still have a leak here if the vlan id
    is other number, so I need to call fdb_delete_by_port(br, NULL, 1)
    to flush all entries whose dst is NULL for the bridge.

Suggested-by: Toshiaki Makita <[email protected]>
Suggested-by: Vlad Yasevich <[email protected]>
Signed-off-by: Ding Tianhong <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
[ luis: backported to 3.11: adjusted context ]
Signed-off-by: Luis Henriques <[email protected]>
Signed-off-by: Brad Figg <[email protected]>
cpaasch pushed a commit that referenced this issue Apr 1, 2014
vmxnet3's netpoll driver is incorrectly coded.  It directly calls
vmxnet3_do_poll, which is the driver internal napi poll routine.  As the netpoll
controller method doesn't block real napi polls in any way, there is a potential
for race conditions in which the netpoll controller method and the napi poll
method run concurrently.  The result is data corruption causing panics such as this
one recently observed:
PID: 1371   TASK: ffff88023762caa0  CPU: 1   COMMAND: "rs:main Q:Reg"
 #0 [ffff88023abd5780] machine_kexec at ffffffff81038f3b
 #1 [ffff88023abd57e0] crash_kexec at ffffffff810c5d92
 #2 [ffff88023abd58b0] oops_end at ffffffff8152b570
 #3 [ffff88023abd58e0] die at ffffffff81010e0b
 #4 [ffff88023abd5910] do_trap at ffffffff8152add4
 #5 [ffff88023abd5970] do_invalid_op at ffffffff8100cf95
 #6 [ffff88023abd5a10] invalid_op at ffffffff8100bf9b
    [exception RIP: vmxnet3_rq_rx_complete+1968]
    RIP: ffffffffa00f1e80  RSP: ffff88023abd5ac8  RFLAGS: 00010086
    RAX: 0000000000000000  RBX: ffff88023b5dcee0  RCX: 00000000000000c0
    RDX: 0000000000000000  RSI: 00000000000005f2  RDI: ffff88023b5dcee0
    RBP: ffff88023abd5b48   R8: 0000000000000000   R9: ffff88023a3b6048
    R10: 0000000000000000  R11: 0000000000000002  R12: ffff8802398d4cd8
    R13: ffff88023af35140  R14: ffff88023b60c890  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #7 [ffff88023abd5b50] vmxnet3_do_poll at ffffffffa00f204a [vmxnet3]
 #8 [ffff88023abd5b80] vmxnet3_netpoll at ffffffffa00f209c [vmxnet3]
 #9 [ffff88023abd5ba0] netpoll_poll_dev at ffffffff81472bb7

The fix is to do as other drivers do, and have the poll controller call the top
half interrupt handler, which schedules a napi poll properly to recieve frames

Tested by myself, successfully.

Signed-off-by: Neil Horman <[email protected]>
CC: Shreyas Bhatewara <[email protected]>
CC: "VMware, Inc." <[email protected]>
CC: "David S. Miller" <[email protected]>
CC: [email protected]
Reviewed-by: Shreyas N Bhatewara <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
cpaasch pushed a commit that referenced this issue Apr 29, 2014
commit b34aa86 upstream.

Mmapping a comedi data buffer with lockdep checking enabled produced the
following kernel debug messages:

======================================================
[ INFO: possible circular locking dependency detected ]
3.5.0-rc3-ija1+ #9 Tainted: G         C
-------------------------------------------------------
comedi_test/4160 is trying to acquire lock:
 (&dev->mutex#2){+.+.+.}, at: [<ffffffffa00313f4>] comedi_mmap+0x57/0x1d9 [comedi]

but task is already holding lock:
 (&mm->mmap_sem){++++++}, at: [<ffffffff810c96fe>] vm_mmap_pgoff+0x41/0x76

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&mm->mmap_sem){++++++}:
       [<ffffffff8106d0e8>] lock_acquire+0x97/0x105
       [<ffffffff810ce3bc>] might_fault+0x6d/0x90
       [<ffffffffa0031ffb>] do_devinfo_ioctl.isra.7+0x11e/0x14c [comedi]
       [<ffffffffa003227f>] comedi_unlocked_ioctl+0x256/0xe48 [comedi]
       [<ffffffff810f7fcd>] vfs_ioctl+0x18/0x34
       [<ffffffff810f87fd>] do_vfs_ioctl+0x382/0x43c
       [<ffffffff810f88f9>] sys_ioctl+0x42/0x65
       [<ffffffff81415c62>] system_call_fastpath+0x16/0x1b

-> #0 (&dev->mutex#2){+.+.+.}:
       [<ffffffff8106c528>] __lock_acquire+0x101d/0x1591
       [<ffffffff8106d0e8>] lock_acquire+0x97/0x105
       [<ffffffff8140c894>] mutex_lock_nested+0x46/0x2a4
       [<ffffffffa00313f4>] comedi_mmap+0x57/0x1d9 [comedi]
       [<ffffffff810d5816>] mmap_region+0x281/0x492
       [<ffffffff810d5c92>] do_mmap_pgoff+0x26b/0x2a7
       [<ffffffff810c971a>] vm_mmap_pgoff+0x5d/0x76
       [<ffffffff810d493f>] sys_mmap_pgoff+0xc7/0x10d
       [<ffffffff81004d36>] sys_mmap+0x16/0x20
       [<ffffffff81415c62>] system_call_fastpath+0x16/0x1b

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&mm->mmap_sem);
                               lock(&dev->mutex#2);
                               lock(&mm->mmap_sem);
  lock(&dev->mutex#2);

 *** DEADLOCK ***

To avoid the circular dependency, just try to get the lock in
`comedi_mmap()` instead of blocking.  Since the comedi device's main mutex
is heavily used, do a down-read of its `attach_lock` rwsemaphore
instead.  Trying to down-read `attach_lock` should only fail if
some task has down-write locked it, and that is only done while the
comedi device is being attached to or detached from a low-level hardware
device.

Unfortunately, acquiring the `attach_lock` doesn't prevent another
task replacing the comedi data buffer we are trying to mmap.  The
details of the buffer are held in a `struct comedi_buf_map` and pointed
to by `s->async->buf_map` where `s` is the comedi subdevice whose buffer
we are trying to map.  The `struct comedi_buf_map` is already reference
counted with a `struct kref`, so we can stop it being freed prematurely.

Modify `comedi_mmap()` to call new function
`comedi_buf_map_from_subdev_get()` to read the subdevice's current
buffer map pointer and increment its reference instead of accessing
`async->buf_map` directly.  Call `comedi_buf_map_put()` to decrement the
reference once the buffer map structure has been dealt with.  (Note that
`comedi_buf_map_put()` does nothing if passed a NULL pointer.)

`comedi_buf_map_from_subdev_get()` checks the subdevice's buffer map
pointer has been set and the buffer map has been initialized enough for
`comedi_mmap()` to deal with it (specifically, check the `n_pages`
member has been set to a non-zero value).  If all is well, the buffer
map's reference is incremented and a pointer to it is returned.  The
comedi subdevice's spin-lock is used to protect the checks.  Also use
the spin-lock in `__comedi_buf_alloc()` and `__comedi_buf_free()` to
protect changes to the subdevice's buffer map structure pointer and the
buffer map structure's `n_pages` member.  (This checking of `n_pages` is
a bit clunky and I [Ian Abbott] plan to deal with it in the future.)

Signed-off-by: Ian Abbott <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
cpaasch pushed a commit that referenced this issue May 4, 2014
BugLink: http://bugs.launchpad.net/bugs/1311196

commit d25f06e upstream.

vmxnet3's netpoll driver is incorrectly coded.  It directly calls
vmxnet3_do_poll, which is the driver internal napi poll routine.  As the netpoll
controller method doesn't block real napi polls in any way, there is a potential
for race conditions in which the netpoll controller method and the napi poll
method run concurrently.  The result is data corruption causing panics such as this
one recently observed:
PID: 1371   TASK: ffff88023762caa0  CPU: 1   COMMAND: "rs:main Q:Reg"
 #0 [ffff88023abd5780] machine_kexec at ffffffff81038f3b
 #1 [ffff88023abd57e0] crash_kexec at ffffffff810c5d92
 #2 [ffff88023abd58b0] oops_end at ffffffff8152b570
 #3 [ffff88023abd58e0] die at ffffffff81010e0b
 #4 [ffff88023abd5910] do_trap at ffffffff8152add4
 #5 [ffff88023abd5970] do_invalid_op at ffffffff8100cf95
 #6 [ffff88023abd5a10] invalid_op at ffffffff8100bf9b
    [exception RIP: vmxnet3_rq_rx_complete+1968]
    RIP: ffffffffa00f1e80  RSP: ffff88023abd5ac8  RFLAGS: 00010086
    RAX: 0000000000000000  RBX: ffff88023b5dcee0  RCX: 00000000000000c0
    RDX: 0000000000000000  RSI: 00000000000005f2  RDI: ffff88023b5dcee0
    RBP: ffff88023abd5b48   R8: 0000000000000000   R9: ffff88023a3b6048
    R10: 0000000000000000  R11: 0000000000000002  R12: ffff8802398d4cd8
    R13: ffff88023af35140  R14: ffff88023b60c890  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #7 [ffff88023abd5b50] vmxnet3_do_poll at ffffffffa00f204a [vmxnet3]
 #8 [ffff88023abd5b80] vmxnet3_netpoll at ffffffffa00f209c [vmxnet3]
 #9 [ffff88023abd5ba0] netpoll_poll_dev at ffffffff81472bb7

The fix is to do as other drivers do, and have the poll controller call the top
half interrupt handler, which schedules a napi poll properly to recieve frames

Tested by myself, successfully.

Signed-off-by: Neil Horman <[email protected]>
CC: Shreyas Bhatewara <[email protected]>
CC: "VMware, Inc." <[email protected]>
CC: "David S. Miller" <[email protected]>
Reviewed-by: Shreyas N Bhatewara <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Luis Henriques <[email protected]>
Signed-off-by: Joseph Salisbury <[email protected]>
cpaasch pushed a commit that referenced this issue Oct 22, 2021
commit 5d388fa upstream.

If a cell has 'nbits' equal to a multiple of BITS_PER_BYTE the logic

 *p &= GENMASK((cell->nbits%BITS_PER_BYTE) - 1, 0);

will become undefined behavior because nbits modulo BITS_PER_BYTE is 0, and we
subtract one from that making a large number that is then shifted more than the
number of bits that fit into an unsigned long.

UBSAN reports this problem:

 UBSAN: shift-out-of-bounds in drivers/nvmem/core.c:1386:8
 shift exponent 64 is too large for 64-bit type 'unsigned long'
 CPU: 6 PID: 7 Comm: kworker/u16:0 Not tainted 5.15.0-rc3+ #9
 Hardware name: Google Lazor (rev3+) with KB Backlight (DT)
 Workqueue: events_unbound deferred_probe_work_func
 Call trace:
  dump_backtrace+0x0/0x170
  show_stack+0x24/0x30
  dump_stack_lvl+0x64/0x7c
  dump_stack+0x18/0x38
  ubsan_epilogue+0x10/0x54
  __ubsan_handle_shift_out_of_bounds+0x180/0x194
  __nvmem_cell_read+0x1ec/0x21c
  nvmem_cell_read+0x58/0x94
  nvmem_cell_read_variable_common+0x4c/0xb0
  nvmem_cell_read_variable_le_u32+0x40/0x100
  a6xx_gpu_init+0x170/0x2f4
  adreno_bind+0x174/0x284
  component_bind_all+0xf0/0x264
  msm_drm_bind+0x1d8/0x7a0
  try_to_bring_up_master+0x164/0x1ac
  __component_add+0xbc/0x13c
  component_add+0x20/0x2c
  dp_display_probe+0x340/0x384
  platform_probe+0xc0/0x100
  really_probe+0x110/0x304
  __driver_probe_device+0xb8/0x120
  driver_probe_device+0x4c/0xfc
  __device_attach_driver+0xb0/0x128
  bus_for_each_drv+0x90/0xdc
  __device_attach+0xc8/0x174
  device_initial_probe+0x20/0x2c
  bus_probe_device+0x40/0xa4
  deferred_probe_work_func+0x7c/0xb8
  process_one_work+0x128/0x21c
  process_scheduled_works+0x40/0x54
  worker_thread+0x1ec/0x2a8
  kthread+0x138/0x158
  ret_from_fork+0x10/0x20

Fix it by making sure there are any bits to mask out.

Fixes: 69aba79 ("nvmem: Add a simple NVMEM framework for consumers")
Cc: Douglas Anderson <[email protected]>
Cc: [email protected]
Signed-off-by: Stephen Boyd <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
matttbe pushed a commit that referenced this issue Jan 7, 2022
commit 5d388fa upstream.

If a cell has 'nbits' equal to a multiple of BITS_PER_BYTE the logic

 *p &= GENMASK((cell->nbits%BITS_PER_BYTE) - 1, 0);

will become undefined behavior because nbits modulo BITS_PER_BYTE is 0, and we
subtract one from that making a large number that is then shifted more than the
number of bits that fit into an unsigned long.

UBSAN reports this problem:

 UBSAN: shift-out-of-bounds in drivers/nvmem/core.c:1386:8
 shift exponent 64 is too large for 64-bit type 'unsigned long'
 CPU: 6 PID: 7 Comm: kworker/u16:0 Not tainted 5.15.0-rc3+ #9
 Hardware name: Google Lazor (rev3+) with KB Backlight (DT)
 Workqueue: events_unbound deferred_probe_work_func
 Call trace:
  dump_backtrace+0x0/0x170
  show_stack+0x24/0x30
  dump_stack_lvl+0x64/0x7c
  dump_stack+0x18/0x38
  ubsan_epilogue+0x10/0x54
  __ubsan_handle_shift_out_of_bounds+0x180/0x194
  __nvmem_cell_read+0x1ec/0x21c
  nvmem_cell_read+0x58/0x94
  nvmem_cell_read_variable_common+0x4c/0xb0
  nvmem_cell_read_variable_le_u32+0x40/0x100
  a6xx_gpu_init+0x170/0x2f4
  adreno_bind+0x174/0x284
  component_bind_all+0xf0/0x264
  msm_drm_bind+0x1d8/0x7a0
  try_to_bring_up_master+0x164/0x1ac
  __component_add+0xbc/0x13c
  component_add+0x20/0x2c
  dp_display_probe+0x340/0x384
  platform_probe+0xc0/0x100
  really_probe+0x110/0x304
  __driver_probe_device+0xb8/0x120
  driver_probe_device+0x4c/0xfc
  __device_attach_driver+0xb0/0x128
  bus_for_each_drv+0x90/0xdc
  __device_attach+0xc8/0x174
  device_initial_probe+0x20/0x2c
  bus_probe_device+0x40/0xa4
  deferred_probe_work_func+0x7c/0xb8
  process_one_work+0x128/0x21c
  process_scheduled_works+0x40/0x54
  worker_thread+0x1ec/0x2a8
  kthread+0x138/0x158
  ret_from_fork+0x10/0x20

Fix it by making sure there are any bits to mask out.

Fixes: 69aba79 ("nvmem: Add a simple NVMEM framework for consumers")
Cc: Douglas Anderson <[email protected]>
Cc: [email protected]
Signed-off-by: Stephen Boyd <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
matttbe pushed a commit that referenced this issue Jan 7, 2022
commit 57f0ff0 upstream.

It's later supposed to be either a correct address or NULL. Without the
initialization, it may contain an undefined value which results in the
following segmentation fault:

  # perf top --sort comm -g --ignore-callees=do_idle

terminates with:

  #0  0x00007ffff56b7685 in __strlen_avx2 () from /lib64/libc.so.6
  #1  0x00007ffff55e3802 in strdup () from /lib64/libc.so.6
  #2  0x00005555558cb139 in hist_entry__init (callchain_size=<optimized out>, sample_self=true, template=0x7fffde7fb110, he=0x7fffd801c250) at util/hist.c:489
  #3  hist_entry__new (template=template@entry=0x7fffde7fb110, sample_self=sample_self@entry=true) at util/hist.c:564
  #4  0x00005555558cb4ba in hists__findnew_entry (hists=hists@entry=0x5555561d9e38, entry=entry@entry=0x7fffde7fb110, al=al@entry=0x7fffde7fb420,
      sample_self=sample_self@entry=true) at util/hist.c:657
  #5  0x00005555558cba1b in __hists__add_entry (hists=hists@entry=0x5555561d9e38, al=0x7fffde7fb420, sym_parent=<optimized out>, bi=bi@entry=0x0, mi=mi@entry=0x0,
      sample=sample@entry=0x7fffde7fb4b0, sample_self=true, ops=0x0, block_info=0x0) at util/hist.c:288
  #6  0x00005555558cbb70 in hists__add_entry (sample_self=true, sample=0x7fffde7fb4b0, mi=0x0, bi=0x0, sym_parent=<optimized out>, al=<optimized out>, hists=0x5555561d9e38)
      at util/hist.c:1056
  #7  iter_add_single_cumulative_entry (iter=0x7fffde7fb460, al=<optimized out>) at util/hist.c:1056
  #8  0x00005555558cc8a4 in hist_entry_iter__add (iter=iter@entry=0x7fffde7fb460, al=al@entry=0x7fffde7fb420, max_stack_depth=<optimized out>, arg=arg@entry=0x7fffffff7db0)
      at util/hist.c:1231
  #9  0x00005555557cdc9a in perf_event__process_sample (machine=<optimized out>, sample=0x7fffde7fb4b0, evsel=<optimized out>, event=<optimized out>, tool=0x7fffffff7db0)
      at builtin-top.c:842
  #10 deliver_event (qe=<optimized out>, qevent=<optimized out>) at builtin-top.c:1202
  #11 0x00005555558a9318 in do_flush (show_progress=false, oe=0x7fffffff80e0) at util/ordered-events.c:244
  #12 __ordered_events__flush (oe=oe@entry=0x7fffffff80e0, how=how@entry=OE_FLUSH__TOP, timestamp=timestamp@entry=0) at util/ordered-events.c:323
  #13 0x00005555558a9789 in __ordered_events__flush (timestamp=<optimized out>, how=<optimized out>, oe=<optimized out>) at util/ordered-events.c:339
  #14 ordered_events__flush (how=OE_FLUSH__TOP, oe=0x7fffffff80e0) at util/ordered-events.c:341
  #15 ordered_events__flush (oe=oe@entry=0x7fffffff80e0, how=how@entry=OE_FLUSH__TOP) at util/ordered-events.c:339
  #16 0x00005555557cd631 in process_thread (arg=0x7fffffff7db0) at builtin-top.c:1114
  #17 0x00007ffff7bb817a in start_thread () from /lib64/libpthread.so.0
  #18 0x00007ffff5656dc3 in clone () from /lib64/libc.so.6

If you look at the frame #2, the code is:

488	 if (he->srcline) {
489          he->srcline = strdup(he->srcline);
490          if (he->srcline == NULL)
491              goto err_rawdata;
492	 }

If he->srcline is not NULL (it is not NULL if it is uninitialized rubbish),
it gets strdupped and strdupping a rubbish random string causes the problem.

Also, if you look at the commit 1fb7d06, it adds the srcline property
into the struct, but not initializing it everywhere needed.

Committer notes:

Now I see, when using --ignore-callees=do_idle we end up here at line
2189 in add_callchain_ip():

2181         if (al.sym != NULL) {
2182                 if (perf_hpp_list.parent && !*parent &&
2183                     symbol__match_regex(al.sym, &parent_regex))
2184                         *parent = al.sym;
2185                 else if (have_ignore_callees && root_al &&
2186                   symbol__match_regex(al.sym, &ignore_callees_regex)) {
2187                         /* Treat this symbol as the root,
2188                            forgetting its callees. */
2189                         *root_al = al;
2190                         callchain_cursor_reset(cursor);
2191                 }
2192         }

And the al that doesn't have the ->srcline field initialized will be
copied to the root_al, so then, back to:

1211 int hist_entry_iter__add(struct hist_entry_iter *iter, struct addr_location *al,
1212                          int max_stack_depth, void *arg)
1213 {
1214         int err, err2;
1215         struct map *alm = NULL;
1216
1217         if (al)
1218                 alm = map__get(al->map);
1219
1220         err = sample__resolve_callchain(iter->sample, &callchain_cursor, &iter->parent,
1221                                         iter->evsel, al, max_stack_depth);
1222         if (err) {
1223                 map__put(alm);
1224                 return err;
1225         }
1226
1227         err = iter->ops->prepare_entry(iter, al);
1228         if (err)
1229                 goto out;
1230
1231         err = iter->ops->add_single_entry(iter, al);
1232         if (err)
1233                 goto out;
1234

That al at line 1221 is what hist_entry_iter__add() (called from
sample__resolve_callchain()) saw as 'root_al', and then:

        iter->ops->add_single_entry(iter, al);

will go on with al->srcline with a bogus value, I'll add the above
sequence to the cset and apply, thanks!

Signed-off-by: Michael Petlan <[email protected]>
CC: Milian Wolff <[email protected]>
Cc: Jiri Olsa <[email protected]>
Fixes: 1fb7d06 ("perf report Use srcline from callchain for hist entries")
Link: https //lore.kernel.org/r/[email protected]
Reported-by: Juri Lelli <[email protected]>
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
matttbe pushed a commit that referenced this issue Jan 7, 2022
commit 5d388fa upstream.

If a cell has 'nbits' equal to a multiple of BITS_PER_BYTE the logic

 *p &= GENMASK((cell->nbits%BITS_PER_BYTE) - 1, 0);

will become undefined behavior because nbits modulo BITS_PER_BYTE is 0, and we
subtract one from that making a large number that is then shifted more than the
number of bits that fit into an unsigned long.

UBSAN reports this problem:

 UBSAN: shift-out-of-bounds in drivers/nvmem/core.c:1386:8
 shift exponent 64 is too large for 64-bit type 'unsigned long'
 CPU: 6 PID: 7 Comm: kworker/u16:0 Not tainted 5.15.0-rc3+ #9
 Hardware name: Google Lazor (rev3+) with KB Backlight (DT)
 Workqueue: events_unbound deferred_probe_work_func
 Call trace:
  dump_backtrace+0x0/0x170
  show_stack+0x24/0x30
  dump_stack_lvl+0x64/0x7c
  dump_stack+0x18/0x38
  ubsan_epilogue+0x10/0x54
  __ubsan_handle_shift_out_of_bounds+0x180/0x194
  __nvmem_cell_read+0x1ec/0x21c
  nvmem_cell_read+0x58/0x94
  nvmem_cell_read_variable_common+0x4c/0xb0
  nvmem_cell_read_variable_le_u32+0x40/0x100
  a6xx_gpu_init+0x170/0x2f4
  adreno_bind+0x174/0x284
  component_bind_all+0xf0/0x264
  msm_drm_bind+0x1d8/0x7a0
  try_to_bring_up_master+0x164/0x1ac
  __component_add+0xbc/0x13c
  component_add+0x20/0x2c
  dp_display_probe+0x340/0x384
  platform_probe+0xc0/0x100
  really_probe+0x110/0x304
  __driver_probe_device+0xb8/0x120
  driver_probe_device+0x4c/0xfc
  __device_attach_driver+0xb0/0x128
  bus_for_each_drv+0x90/0xdc
  __device_attach+0xc8/0x174
  device_initial_probe+0x20/0x2c
  bus_probe_device+0x40/0xa4
  deferred_probe_work_func+0x7c/0xb8
  process_one_work+0x128/0x21c
  process_scheduled_works+0x40/0x54
  worker_thread+0x1ec/0x2a8
  kthread+0x138/0x158
  ret_from_fork+0x10/0x20

Fix it by making sure there are any bits to mask out.

Fixes: 69aba79 ("nvmem: Add a simple NVMEM framework for consumers")
Cc: Douglas Anderson <[email protected]>
Cc: [email protected]
Signed-off-by: Stephen Boyd <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
dreibh pushed a commit to dreibh/mptcp that referenced this issue Feb 7, 2022
[ Upstream commit df1f679d19edb9eeb67cc2f96b29375f21991945 ]

KeyWest i2c @0xf8001003 irq 42 /uni-n@f8000000/i2c@f8001000
BUG: key c2d00cbc has not been registered!
------------[ cut here ]------------
DEBUG_LOCKS_WARN_ON(1)
WARNING: CPU: 0 PID: 1 at kernel/locking/lockdep.c:4801 lockdep_init_map_type+0x4c0/0xb4c
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.15.5-gentoo-PowerMacG4 multipath-tcp#9
NIP:  c01a9428 LR: c01a9428 CTR: 00000000
REGS: e1033cf0 TRAP: 0700   Not tainted  (5.15.5-gentoo-PowerMacG4)
MSR:  00029032 <EE,ME,IR,DR,RI>  CR: 24002002  XER: 00000000

GPR00: c01a9428 e1033db0 c2d1cf20 00000016 00000004 00000001 c01c0630 e1033a73
GPR08: 00000000 00000000 00000000 e1033db0 24002004 00000000 f8729377 00000003
GPR16: c1829a9c 00000000 18305357 c1416fc0 c1416f80 c006ac60 c2d00ca8 c1416f00
GPR24: 00000000 c21586f0 c2160000 00000000 c2d00cbc c2170000 c216e1a0 c2160000
NIP [c01a9428] lockdep_init_map_type+0x4c0/0xb4c
LR [c01a9428] lockdep_init_map_type+0x4c0/0xb4c
Call Trace:
[e1033db0] [c01a9428] lockdep_init_map_type+0x4c0/0xb4c (unreliable)
[e1033df0] [c1c177b8] kw_i2c_add+0x334/0x424
[e1033e20] [c1c18294] pmac_i2c_init+0x9ec/0xa9c
[e1033e80] [c1c1a790] smp_core99_probe+0xbc/0x35c
[e1033eb0] [c1c03cb0] kernel_init_freeable+0x190/0x5a4
[e1033f10] [c000946c] kernel_init+0x28/0x154
[e1033f30] [c0035148] ret_from_kernel_thread+0x14/0x1c

Add missing lockdep_register_key()

Reported-by: Erhard Furtner <[email protected]>
Signed-off-by: Christophe Leroy <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/69e4f55565bb45ebb0843977801b245af0c666fe.1638264741.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <[email protected]>
dreibh pushed a commit to dreibh/mptcp that referenced this issue Mar 21, 2022
[ Upstream commit 4224cfd7fb6523f7a9d1c8bb91bb5df1e38eb624 ]

When bringing down the netdevice or system shutdown, a panic can be
triggered while accessing the sysfs path because the device is already
removed.

    [  755.549084] mlx5_core 0000:12:00.1: Shutdown was called
    [  756.404455] mlx5_core 0000:12:00.0: Shutdown was called
    ...
    [  757.937260] BUG: unable to handle kernel NULL pointer dereference at           (null)
    [  758.031397] IP: [<ffffffff8ee11acb>] dma_pool_alloc+0x1ab/0x280

    crash> bt
    ...
    PID: 12649  TASK: ffff8924108f2100  CPU: 1   COMMAND: "amsd"
    ...
     multipath-tcp#9 [ffff89240e1a38b0] page_fault at ffffffff8f38c778
        [exception RIP: dma_pool_alloc+0x1ab]
        RIP: ffffffff8ee11acb  RSP: ffff89240e1a3968  RFLAGS: 00010046
        RAX: 0000000000000246  RBX: ffff89243d874100  RCX: 0000000000001000
        RDX: 0000000000000000  RSI: 0000000000000246  RDI: ffff89243d874090
        RBP: ffff89240e1a39c0   R8: 000000000001f080   R9: ffff8905ffc03c00
        R10: ffffffffc04680d4  R11: ffffffff8edde9fd  R12: 00000000000080d0
        R13: ffff89243d874090  R14: ffff89243d874080  R15: 0000000000000000
        ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
    multipath-tcp#10 [ffff89240e1a39c8] mlx5_alloc_cmd_msg at ffffffffc04680f3 [mlx5_core]
    multipath-tcp#11 [ffff89240e1a3a18] cmd_exec at ffffffffc046ad62 [mlx5_core]
    multipath-tcp#12 [ffff89240e1a3ab8] mlx5_cmd_exec at ffffffffc046b4fb [mlx5_core]
    multipath-tcp#13 [ffff89240e1a3ae8] mlx5_core_access_reg at ffffffffc0475434 [mlx5_core]
    multipath-tcp#14 [ffff89240e1a3b40] mlx5e_get_fec_caps at ffffffffc04a7348 [mlx5_core]
    multipath-tcp#15 [ffff89240e1a3bb0] get_fec_supported_advertised at ffffffffc04992bf [mlx5_core]
    multipath-tcp#16 [ffff89240e1a3c08] mlx5e_get_link_ksettings at ffffffffc049ab36 [mlx5_core]
    multipath-tcp#17 [ffff89240e1a3ce8] __ethtool_get_link_ksettings at ffffffff8f25db46
    multipath-tcp#18 [ffff89240e1a3d48] speed_show at ffffffff8f277208
    multipath-tcp#19 [ffff89240e1a3dd8] dev_attr_show at ffffffff8f0b70e3
    multipath-tcp#20 [ffff89240e1a3df8] sysfs_kf_seq_show at ffffffff8eedbedf
    multipath-tcp#21 [ffff89240e1a3e18] kernfs_seq_show at ffffffff8eeda596
    multipath-tcp#22 [ffff89240e1a3e28] seq_read at ffffffff8ee76d10
    multipath-tcp#23 [ffff89240e1a3e98] kernfs_fop_read at ffffffff8eedaef5
    multipath-tcp#24 [ffff89240e1a3ed8] vfs_read at ffffffff8ee4e3ff
    multipath-tcp#25 [ffff89240e1a3f08] sys_read at ffffffff8ee4f27f
    multipath-tcp#26 [ffff89240e1a3f50] system_call_fastpath at ffffffff8f395f92

    crash> net_device.state ffff89443b0c0000
      state = 0x5  (__LINK_STATE_START| __LINK_STATE_NOCARRIER)

To prevent this scenario, we also make sure that the netdevice is present.

Signed-off-by: suresh kumar <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
dreibh pushed a commit to dreibh/mptcp that referenced this issue Mar 21, 2022
[ Upstream commit 4224cfd7fb6523f7a9d1c8bb91bb5df1e38eb624 ]

When bringing down the netdevice or system shutdown, a panic can be
triggered while accessing the sysfs path because the device is already
removed.

    [  755.549084] mlx5_core 0000:12:00.1: Shutdown was called
    [  756.404455] mlx5_core 0000:12:00.0: Shutdown was called
    ...
    [  757.937260] BUG: unable to handle kernel NULL pointer dereference at           (null)
    [  758.031397] IP: [<ffffffff8ee11acb>] dma_pool_alloc+0x1ab/0x280

    crash> bt
    ...
    PID: 12649  TASK: ffff8924108f2100  CPU: 1   COMMAND: "amsd"
    ...
     multipath-tcp#9 [ffff89240e1a38b0] page_fault at ffffffff8f38c778
        [exception RIP: dma_pool_alloc+0x1ab]
        RIP: ffffffff8ee11acb  RSP: ffff89240e1a3968  RFLAGS: 00010046
        RAX: 0000000000000246  RBX: ffff89243d874100  RCX: 0000000000001000
        RDX: 0000000000000000  RSI: 0000000000000246  RDI: ffff89243d874090
        RBP: ffff89240e1a39c0   R8: 000000000001f080   R9: ffff8905ffc03c00
        R10: ffffffffc04680d4  R11: ffffffff8edde9fd  R12: 00000000000080d0
        R13: ffff89243d874090  R14: ffff89243d874080  R15: 0000000000000000
        ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
    multipath-tcp#10 [ffff89240e1a39c8] mlx5_alloc_cmd_msg at ffffffffc04680f3 [mlx5_core]
    multipath-tcp#11 [ffff89240e1a3a18] cmd_exec at ffffffffc046ad62 [mlx5_core]
    multipath-tcp#12 [ffff89240e1a3ab8] mlx5_cmd_exec at ffffffffc046b4fb [mlx5_core]
    multipath-tcp#13 [ffff89240e1a3ae8] mlx5_core_access_reg at ffffffffc0475434 [mlx5_core]
    multipath-tcp#14 [ffff89240e1a3b40] mlx5e_get_fec_caps at ffffffffc04a7348 [mlx5_core]
    multipath-tcp#15 [ffff89240e1a3bb0] get_fec_supported_advertised at ffffffffc04992bf [mlx5_core]
    multipath-tcp#16 [ffff89240e1a3c08] mlx5e_get_link_ksettings at ffffffffc049ab36 [mlx5_core]
    multipath-tcp#17 [ffff89240e1a3ce8] __ethtool_get_link_ksettings at ffffffff8f25db46
    multipath-tcp#18 [ffff89240e1a3d48] speed_show at ffffffff8f277208
    multipath-tcp#19 [ffff89240e1a3dd8] dev_attr_show at ffffffff8f0b70e3
    multipath-tcp#20 [ffff89240e1a3df8] sysfs_kf_seq_show at ffffffff8eedbedf
    multipath-tcp#21 [ffff89240e1a3e18] kernfs_seq_show at ffffffff8eeda596
    multipath-tcp#22 [ffff89240e1a3e28] seq_read at ffffffff8ee76d10
    multipath-tcp#23 [ffff89240e1a3e98] kernfs_fop_read at ffffffff8eedaef5
    multipath-tcp#24 [ffff89240e1a3ed8] vfs_read at ffffffff8ee4e3ff
    multipath-tcp#25 [ffff89240e1a3f08] sys_read at ffffffff8ee4f27f
    multipath-tcp#26 [ffff89240e1a3f50] system_call_fastpath at ffffffff8f395f92

    crash> net_device.state ffff89443b0c0000
      state = 0x5  (__LINK_STATE_START| __LINK_STATE_NOCARRIER)

To prevent this scenario, we also make sure that the netdevice is present.

Signed-off-by: suresh kumar <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
matttbe pushed a commit that referenced this issue Apr 21, 2022
[ Upstream commit 9d7cbe2b9cf5f650067df4f402fdd799d4bbb4e1 ]

kvartet reported, that hci_uart_tx_wakeup() uses uninitialized rwsem.
The problem was in wrong place for percpu_init_rwsem() call.

hci_uart_proto::open() may register a timer whose callback may call
hci_uart_tx_wakeup(). There is a chance, that hci_uart_register_device()
thread won't be fast enough to call percpu_init_rwsem().

Fix it my moving percpu_init_rwsem() call before p->open().

INFO: trying to register non-static key.
The code is fine but needs lockdep annotation, or maybe
you didn't initialize this object before use?
turning off the locking correctness validator.
CPU: 2 PID: 18524 Comm: syz-executor.5 Not tainted 5.16.0-rc6 #9
...
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 assign_lock_key kernel/locking/lockdep.c:951 [inline]
 register_lock_class+0x148d/0x1950 kernel/locking/lockdep.c:1263
 __lock_acquire+0x106/0x57e0 kernel/locking/lockdep.c:4906
 lock_acquire kernel/locking/lockdep.c:5637 [inline]
 lock_acquire+0x1ab/0x520 kernel/locking/lockdep.c:5602
 percpu_down_read_trylock include/linux/percpu-rwsem.h:92 [inline]
 hci_uart_tx_wakeup+0x12e/0x490 drivers/bluetooth/hci_ldisc.c:124
 h5_timed_event+0x32f/0x6a0 drivers/bluetooth/hci_h5.c:188
 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421

Fixes: d73e172 ("Bluetooth: hci_serdev: Init hci_uart proto_lock to avoid oops")
Reported-by: Yiru Xu <[email protected]>
Signed-off-by: Pavel Skripkin <[email protected]>
Signed-off-by: Marcel Holtmann <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
matttbe pushed a commit that referenced this issue Apr 21, 2022
[ Upstream commit 9d7cbe2b9cf5f650067df4f402fdd799d4bbb4e1 ]

kvartet reported, that hci_uart_tx_wakeup() uses uninitialized rwsem.
The problem was in wrong place for percpu_init_rwsem() call.

hci_uart_proto::open() may register a timer whose callback may call
hci_uart_tx_wakeup(). There is a chance, that hci_uart_register_device()
thread won't be fast enough to call percpu_init_rwsem().

Fix it my moving percpu_init_rwsem() call before p->open().

INFO: trying to register non-static key.
The code is fine but needs lockdep annotation, or maybe
you didn't initialize this object before use?
turning off the locking correctness validator.
CPU: 2 PID: 18524 Comm: syz-executor.5 Not tainted 5.16.0-rc6 #9
...
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 assign_lock_key kernel/locking/lockdep.c:951 [inline]
 register_lock_class+0x148d/0x1950 kernel/locking/lockdep.c:1263
 __lock_acquire+0x106/0x57e0 kernel/locking/lockdep.c:4906
 lock_acquire kernel/locking/lockdep.c:5637 [inline]
 lock_acquire+0x1ab/0x520 kernel/locking/lockdep.c:5602
 percpu_down_read_trylock include/linux/percpu-rwsem.h:92 [inline]
 hci_uart_tx_wakeup+0x12e/0x490 drivers/bluetooth/hci_ldisc.c:124
 h5_timed_event+0x32f/0x6a0 drivers/bluetooth/hci_h5.c:188
 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421

Fixes: d73e172 ("Bluetooth: hci_serdev: Init hci_uart proto_lock to avoid oops")
Reported-by: Yiru Xu <[email protected]>
Signed-off-by: Pavel Skripkin <[email protected]>
Signed-off-by: Marcel Holtmann <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
matttbe pushed a commit that referenced this issue Apr 21, 2022
[ Upstream commit 4224cfd7fb6523f7a9d1c8bb91bb5df1e38eb624 ]

When bringing down the netdevice or system shutdown, a panic can be
triggered while accessing the sysfs path because the device is already
removed.

    [  755.549084] mlx5_core 0000:12:00.1: Shutdown was called
    [  756.404455] mlx5_core 0000:12:00.0: Shutdown was called
    ...
    [  757.937260] BUG: unable to handle kernel NULL pointer dereference at           (null)
    [  758.031397] IP: [<ffffffff8ee11acb>] dma_pool_alloc+0x1ab/0x280

    crash> bt
    ...
    PID: 12649  TASK: ffff8924108f2100  CPU: 1   COMMAND: "amsd"
    ...
     #9 [ffff89240e1a38b0] page_fault at ffffffff8f38c778
        [exception RIP: dma_pool_alloc+0x1ab]
        RIP: ffffffff8ee11acb  RSP: ffff89240e1a3968  RFLAGS: 00010046
        RAX: 0000000000000246  RBX: ffff89243d874100  RCX: 0000000000001000
        RDX: 0000000000000000  RSI: 0000000000000246  RDI: ffff89243d874090
        RBP: ffff89240e1a39c0   R8: 000000000001f080   R9: ffff8905ffc03c00
        R10: ffffffffc04680d4  R11: ffffffff8edde9fd  R12: 00000000000080d0
        R13: ffff89243d874090  R14: ffff89243d874080  R15: 0000000000000000
        ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
    #10 [ffff89240e1a39c8] mlx5_alloc_cmd_msg at ffffffffc04680f3 [mlx5_core]
    #11 [ffff89240e1a3a18] cmd_exec at ffffffffc046ad62 [mlx5_core]
    #12 [ffff89240e1a3ab8] mlx5_cmd_exec at ffffffffc046b4fb [mlx5_core]
    #13 [ffff89240e1a3ae8] mlx5_core_access_reg at ffffffffc0475434 [mlx5_core]
    #14 [ffff89240e1a3b40] mlx5e_get_fec_caps at ffffffffc04a7348 [mlx5_core]
    #15 [ffff89240e1a3bb0] get_fec_supported_advertised at ffffffffc04992bf [mlx5_core]
    #16 [ffff89240e1a3c08] mlx5e_get_link_ksettings at ffffffffc049ab36 [mlx5_core]
    #17 [ffff89240e1a3ce8] __ethtool_get_link_ksettings at ffffffff8f25db46
    #18 [ffff89240e1a3d48] speed_show at ffffffff8f277208
    #19 [ffff89240e1a3dd8] dev_attr_show at ffffffff8f0b70e3
    #20 [ffff89240e1a3df8] sysfs_kf_seq_show at ffffffff8eedbedf
    #21 [ffff89240e1a3e18] kernfs_seq_show at ffffffff8eeda596
    #22 [ffff89240e1a3e28] seq_read at ffffffff8ee76d10
    #23 [ffff89240e1a3e98] kernfs_fop_read at ffffffff8eedaef5
    #24 [ffff89240e1a3ed8] vfs_read at ffffffff8ee4e3ff
    #25 [ffff89240e1a3f08] sys_read at ffffffff8ee4f27f
    #26 [ffff89240e1a3f50] system_call_fastpath at ffffffff8f395f92

    crash> net_device.state ffff89443b0c0000
      state = 0x5  (__LINK_STATE_START| __LINK_STATE_NOCARRIER)

To prevent this scenario, we also make sure that the netdevice is present.

Signed-off-by: suresh kumar <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
dreibh pushed a commit to dreibh/mptcp that referenced this issue May 16, 2022
[ Upstream commit af68656d66eda219b7f55ce8313a1da0312c79e1 ]

While handling PCI errors (AER flow) driver tries to
disable NAPI [napi_disable()] after NAPI is deleted
[__netif_napi_del()] which causes unexpected system
hang/crash.

System message log shows the following:
=======================================
[ 3222.537510] EEH: Detected PCI bus error on PHB#384-PE#800000 [ 3222.537511] EEH: This PCI device has failed 2 times in the last hour and will be permanently disabled after 5 failures.
[ 3222.537512] EEH: Notify device drivers to shutdown [ 3222.537513] EEH: Beginning: 'error_detected(IO frozen)'
[ 3222.537514] EEH: PE#800000 (PCI 0384:80:00.0): Invoking
bnx2x->error_detected(IO frozen)
[ 3222.537516] bnx2x: [bnx2x_io_error_detected:14236(eth14)]IO error detected [ 3222.537650] EEH: PE#800000 (PCI 0384:80:00.0): bnx2x driver reports:
'need reset'
[ 3222.537651] EEH: PE#800000 (PCI 0384:80:00.1): Invoking
bnx2x->error_detected(IO frozen)
[ 3222.537651] bnx2x: [bnx2x_io_error_detected:14236(eth13)]IO error detected [ 3222.537729] EEH: PE#800000 (PCI 0384:80:00.1): bnx2x driver reports:
'need reset'
[ 3222.537729] EEH: Finished:'error_detected(IO frozen)' with aggregate recovery state:'need reset'
[ 3222.537890] EEH: Collect temporary log [ 3222.583481] EEH: of node=0384:80:00.0 [ 3222.583519] EEH: PCI device/vendor: 168e14e4 [ 3222.583557] EEH: PCI cmd/status register: 00100140 [ 3222.583557] EEH: PCI-E capabilities and status follow:
[ 3222.583744] EEH: PCI-E 00: 00020010 012c8da2 00095d5e 00455c82 [ 3222.583892] EEH: PCI-E 10: 10820000 00000000 00000000 00000000 [ 3222.583893] EEH: PCI-E 20: 00000000 [ 3222.583893] EEH: PCI-E AER capability register set follows:
[ 3222.584079] EEH: PCI-E AER 00: 13c10001 00000000 00000000 00062030 [ 3222.584230] EEH: PCI-E AER 10: 00002000 000031c0 000001e0 00000000 [ 3222.584378] EEH: PCI-E AER 20: 00000000 00000000 00000000 00000000 [ 3222.584416] EEH: PCI-E AER 30: 00000000 00000000 [ 3222.584416] EEH: of node=0384:80:00.1 [ 3222.584454] EEH: PCI device/vendor: 168e14e4 [ 3222.584491] EEH: PCI cmd/status register: 00100140 [ 3222.584492] EEH: PCI-E capabilities and status follow:
[ 3222.584677] EEH: PCI-E 00: 00020010 012c8da2 00095d5e 00455c82 [ 3222.584825] EEH: PCI-E 10: 10820000 00000000 00000000 00000000 [ 3222.584826] EEH: PCI-E 20: 00000000 [ 3222.584826] EEH: PCI-E AER capability register set follows:
[ 3222.585011] EEH: PCI-E AER 00: 13c10001 00000000 00000000 00062030 [ 3222.585160] EEH: PCI-E AER 10: 00002000 000031c0 000001e0 00000000 [ 3222.585309] EEH: PCI-E AER 20: 00000000 00000000 00000000 00000000 [ 3222.585347] EEH: PCI-E AER 30: 00000000 00000000 [ 3222.586872] RTAS: event: 5, Type: Platform Error (224), Severity: 2 [ 3222.586873] EEH: Reset without hotplug activity [ 3224.762767] EEH: Beginning: 'slot_reset'
[ 3224.762770] EEH: PE#800000 (PCI 0384:80:00.0): Invoking
bnx2x->slot_reset()
[ 3224.762771] bnx2x: [bnx2x_io_slot_reset:14271(eth14)]IO slot reset initializing...
[ 3224.762887] bnx2x 0384:80:00.0: enabling device (0140 -> 0142) [ 3224.768157] bnx2x: [bnx2x_io_slot_reset:14287(eth14)]IO slot reset
--> driver unload

Uninterruptible tasks
=====================
crash> ps | grep UN
     213      2  11  c000000004c89e00  UN   0.0       0      0  [eehd]
     215      2   0  c000000004c80000  UN   0.0       0      0
[kworker/0:2]
    2196      1  28  c000000004504f00  UN   0.1   15936  11136  wickedd
    4287      1   9  c00000020d076800  UN   0.0    4032   3008  agetty
    4289      1  20  c00000020d056680  UN   0.0    7232   3840  agetty
   32423      2  26  c00000020038c580  UN   0.0       0      0
[kworker/26:3]
   32871   4241  27  c0000002609ddd00  UN   0.1   18624  11648  sshd
   32920  10130  16  c00000027284a100  UN   0.1   48512  12608  sendmail
   33092  32987   0  c000000205218b00  UN   0.1   48512  12608  sendmail
   33154   4567  16  c000000260e51780  UN   0.1   48832  12864  pickup
   33209   4241  36  c000000270cb6500  UN   0.1   18624  11712  sshd
   33473  33283   0  c000000205211480  UN   0.1   48512  12672  sendmail
   33531   4241  37  c00000023c902780  UN   0.1   18624  11648  sshd

EEH handler hung while bnx2x sleeping and holding RTNL lock
===========================================================
crash> bt 213
PID: 213    TASK: c000000004c89e00  CPU: 11  COMMAND: "eehd"
  #0 [c000000004d477e0] __schedule at c000000000c70808
  #1 [c000000004d478b0] schedule at c000000000c70ee0
  multipath-tcp#2 [c000000004d478e0] schedule_timeout at c000000000c76dec
  multipath-tcp#3 [c000000004d479c0] msleep at c0000000002120cc
  multipath-tcp#4 [c000000004d479f0] napi_disable at c000000000a06448
                                        ^^^^^^^^^^^^^^^^
  multipath-tcp#5 [c000000004d47a30] bnx2x_netif_stop at c0080000018dba94 [bnx2x]
  multipath-tcp#6 [c000000004d47a60] bnx2x_io_slot_reset at c0080000018a551c [bnx2x]
  multipath-tcp#7 [c000000004d47b20] eeh_report_reset at c00000000004c9bc
  multipath-tcp#8 [c000000004d47b90] eeh_pe_report at c00000000004d1a8
  multipath-tcp#9 [c000000004d47c40] eeh_handle_normal_event at c00000000004da64

And the sleeping source code
============================
crash> dis -ls c000000000a06448
FILE: ../net/core/dev.c
LINE: 6702

   6697  {
   6698          might_sleep();
   6699          set_bit(NAPI_STATE_DISABLE, &n->state);
   6700
   6701          while (test_and_set_bit(NAPI_STATE_SCHED, &n->state))
* 6702                  msleep(1);
   6703          while (test_and_set_bit(NAPI_STATE_NPSVC, &n->state))
   6704                  msleep(1);
   6705
   6706          hrtimer_cancel(&n->timer);
   6707
   6708          clear_bit(NAPI_STATE_DISABLE, &n->state);
   6709  }

EEH calls into bnx2x twice based on the system log above, first through
bnx2x_io_error_detected() and then bnx2x_io_slot_reset(), and executes
the following call chains:

bnx2x_io_error_detected()
  +-> bnx2x_eeh_nic_unload()
       +-> bnx2x_del_all_napi()
            +-> __netif_napi_del()

bnx2x_io_slot_reset()
  +-> bnx2x_netif_stop()
       +-> bnx2x_napi_disable()
            +->napi_disable()

Fix this by correcting the sequence of NAPI APIs usage,
that is delete the NAPI after disabling it.

Fixes: 7fa6f34 ("bnx2x: AER revised")
Reported-by: David Christensen <[email protected]>
Tested-by: David Christensen <[email protected]>
Signed-off-by: Manish Chopra <[email protected]>
Signed-off-by: Ariel Elior <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
dreibh pushed a commit to dreibh/mptcp that referenced this issue May 16, 2022
[ Upstream commit af68656d66eda219b7f55ce8313a1da0312c79e1 ]

While handling PCI errors (AER flow) driver tries to
disable NAPI [napi_disable()] after NAPI is deleted
[__netif_napi_del()] which causes unexpected system
hang/crash.

System message log shows the following:
=======================================
[ 3222.537510] EEH: Detected PCI bus error on PHB#384-PE#800000 [ 3222.537511] EEH: This PCI device has failed 2 times in the last hour and will be permanently disabled after 5 failures.
[ 3222.537512] EEH: Notify device drivers to shutdown [ 3222.537513] EEH: Beginning: 'error_detected(IO frozen)'
[ 3222.537514] EEH: PE#800000 (PCI 0384:80:00.0): Invoking
bnx2x->error_detected(IO frozen)
[ 3222.537516] bnx2x: [bnx2x_io_error_detected:14236(eth14)]IO error detected [ 3222.537650] EEH: PE#800000 (PCI 0384:80:00.0): bnx2x driver reports:
'need reset'
[ 3222.537651] EEH: PE#800000 (PCI 0384:80:00.1): Invoking
bnx2x->error_detected(IO frozen)
[ 3222.537651] bnx2x: [bnx2x_io_error_detected:14236(eth13)]IO error detected [ 3222.537729] EEH: PE#800000 (PCI 0384:80:00.1): bnx2x driver reports:
'need reset'
[ 3222.537729] EEH: Finished:'error_detected(IO frozen)' with aggregate recovery state:'need reset'
[ 3222.537890] EEH: Collect temporary log [ 3222.583481] EEH: of node=0384:80:00.0 [ 3222.583519] EEH: PCI device/vendor: 168e14e4 [ 3222.583557] EEH: PCI cmd/status register: 00100140 [ 3222.583557] EEH: PCI-E capabilities and status follow:
[ 3222.583744] EEH: PCI-E 00: 00020010 012c8da2 00095d5e 00455c82 [ 3222.583892] EEH: PCI-E 10: 10820000 00000000 00000000 00000000 [ 3222.583893] EEH: PCI-E 20: 00000000 [ 3222.583893] EEH: PCI-E AER capability register set follows:
[ 3222.584079] EEH: PCI-E AER 00: 13c10001 00000000 00000000 00062030 [ 3222.584230] EEH: PCI-E AER 10: 00002000 000031c0 000001e0 00000000 [ 3222.584378] EEH: PCI-E AER 20: 00000000 00000000 00000000 00000000 [ 3222.584416] EEH: PCI-E AER 30: 00000000 00000000 [ 3222.584416] EEH: of node=0384:80:00.1 [ 3222.584454] EEH: PCI device/vendor: 168e14e4 [ 3222.584491] EEH: PCI cmd/status register: 00100140 [ 3222.584492] EEH: PCI-E capabilities and status follow:
[ 3222.584677] EEH: PCI-E 00: 00020010 012c8da2 00095d5e 00455c82 [ 3222.584825] EEH: PCI-E 10: 10820000 00000000 00000000 00000000 [ 3222.584826] EEH: PCI-E 20: 00000000 [ 3222.584826] EEH: PCI-E AER capability register set follows:
[ 3222.585011] EEH: PCI-E AER 00: 13c10001 00000000 00000000 00062030 [ 3222.585160] EEH: PCI-E AER 10: 00002000 000031c0 000001e0 00000000 [ 3222.585309] EEH: PCI-E AER 20: 00000000 00000000 00000000 00000000 [ 3222.585347] EEH: PCI-E AER 30: 00000000 00000000 [ 3222.586872] RTAS: event: 5, Type: Platform Error (224), Severity: 2 [ 3222.586873] EEH: Reset without hotplug activity [ 3224.762767] EEH: Beginning: 'slot_reset'
[ 3224.762770] EEH: PE#800000 (PCI 0384:80:00.0): Invoking
bnx2x->slot_reset()
[ 3224.762771] bnx2x: [bnx2x_io_slot_reset:14271(eth14)]IO slot reset initializing...
[ 3224.762887] bnx2x 0384:80:00.0: enabling device (0140 -> 0142) [ 3224.768157] bnx2x: [bnx2x_io_slot_reset:14287(eth14)]IO slot reset
--> driver unload

Uninterruptible tasks
=====================
crash> ps | grep UN
     213      2  11  c000000004c89e00  UN   0.0       0      0  [eehd]
     215      2   0  c000000004c80000  UN   0.0       0      0
[kworker/0:2]
    2196      1  28  c000000004504f00  UN   0.1   15936  11136  wickedd
    4287      1   9  c00000020d076800  UN   0.0    4032   3008  agetty
    4289      1  20  c00000020d056680  UN   0.0    7232   3840  agetty
   32423      2  26  c00000020038c580  UN   0.0       0      0
[kworker/26:3]
   32871   4241  27  c0000002609ddd00  UN   0.1   18624  11648  sshd
   32920  10130  16  c00000027284a100  UN   0.1   48512  12608  sendmail
   33092  32987   0  c000000205218b00  UN   0.1   48512  12608  sendmail
   33154   4567  16  c000000260e51780  UN   0.1   48832  12864  pickup
   33209   4241  36  c000000270cb6500  UN   0.1   18624  11712  sshd
   33473  33283   0  c000000205211480  UN   0.1   48512  12672  sendmail
   33531   4241  37  c00000023c902780  UN   0.1   18624  11648  sshd

EEH handler hung while bnx2x sleeping and holding RTNL lock
===========================================================
crash> bt 213
PID: 213    TASK: c000000004c89e00  CPU: 11  COMMAND: "eehd"
  #0 [c000000004d477e0] __schedule at c000000000c70808
  #1 [c000000004d478b0] schedule at c000000000c70ee0
  multipath-tcp#2 [c000000004d478e0] schedule_timeout at c000000000c76dec
  multipath-tcp#3 [c000000004d479c0] msleep at c0000000002120cc
  multipath-tcp#4 [c000000004d479f0] napi_disable at c000000000a06448
                                        ^^^^^^^^^^^^^^^^
  multipath-tcp#5 [c000000004d47a30] bnx2x_netif_stop at c0080000018dba94 [bnx2x]
  multipath-tcp#6 [c000000004d47a60] bnx2x_io_slot_reset at c0080000018a551c [bnx2x]
  multipath-tcp#7 [c000000004d47b20] eeh_report_reset at c00000000004c9bc
  multipath-tcp#8 [c000000004d47b90] eeh_pe_report at c00000000004d1a8
  multipath-tcp#9 [c000000004d47c40] eeh_handle_normal_event at c00000000004da64

And the sleeping source code
============================
crash> dis -ls c000000000a06448
FILE: ../net/core/dev.c
LINE: 6702

   6697  {
   6698          might_sleep();
   6699          set_bit(NAPI_STATE_DISABLE, &n->state);
   6700
   6701          while (test_and_set_bit(NAPI_STATE_SCHED, &n->state))
* 6702                  msleep(1);
   6703          while (test_and_set_bit(NAPI_STATE_NPSVC, &n->state))
   6704                  msleep(1);
   6705
   6706          hrtimer_cancel(&n->timer);
   6707
   6708          clear_bit(NAPI_STATE_DISABLE, &n->state);
   6709  }

EEH calls into bnx2x twice based on the system log above, first through
bnx2x_io_error_detected() and then bnx2x_io_slot_reset(), and executes
the following call chains:

bnx2x_io_error_detected()
  +-> bnx2x_eeh_nic_unload()
       +-> bnx2x_del_all_napi()
            +-> __netif_napi_del()

bnx2x_io_slot_reset()
  +-> bnx2x_netif_stop()
       +-> bnx2x_napi_disable()
            +->napi_disable()

Fix this by correcting the sequence of NAPI APIs usage,
that is delete the NAPI after disabling it.

Fixes: 7fa6f34 ("bnx2x: AER revised")
Reported-by: David Christensen <[email protected]>
Tested-by: David Christensen <[email protected]>
Signed-off-by: Manish Chopra <[email protected]>
Signed-off-by: Ariel Elior <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
matttbe pushed a commit that referenced this issue May 16, 2022
[ Upstream commit af68656d66eda219b7f55ce8313a1da0312c79e1 ]

While handling PCI errors (AER flow) driver tries to
disable NAPI [napi_disable()] after NAPI is deleted
[__netif_napi_del()] which causes unexpected system
hang/crash.

System message log shows the following:
=======================================
[ 3222.537510] EEH: Detected PCI bus error on PHB#384-PE#800000 [ 3222.537511] EEH: This PCI device has failed 2 times in the last hour and will be permanently disabled after 5 failures.
[ 3222.537512] EEH: Notify device drivers to shutdown [ 3222.537513] EEH: Beginning: 'error_detected(IO frozen)'
[ 3222.537514] EEH: PE#800000 (PCI 0384:80:00.0): Invoking
bnx2x->error_detected(IO frozen)
[ 3222.537516] bnx2x: [bnx2x_io_error_detected:14236(eth14)]IO error detected [ 3222.537650] EEH: PE#800000 (PCI 0384:80:00.0): bnx2x driver reports:
'need reset'
[ 3222.537651] EEH: PE#800000 (PCI 0384:80:00.1): Invoking
bnx2x->error_detected(IO frozen)
[ 3222.537651] bnx2x: [bnx2x_io_error_detected:14236(eth13)]IO error detected [ 3222.537729] EEH: PE#800000 (PCI 0384:80:00.1): bnx2x driver reports:
'need reset'
[ 3222.537729] EEH: Finished:'error_detected(IO frozen)' with aggregate recovery state:'need reset'
[ 3222.537890] EEH: Collect temporary log [ 3222.583481] EEH: of node=0384:80:00.0 [ 3222.583519] EEH: PCI device/vendor: 168e14e4 [ 3222.583557] EEH: PCI cmd/status register: 00100140 [ 3222.583557] EEH: PCI-E capabilities and status follow:
[ 3222.583744] EEH: PCI-E 00: 00020010 012c8da2 00095d5e 00455c82 [ 3222.583892] EEH: PCI-E 10: 10820000 00000000 00000000 00000000 [ 3222.583893] EEH: PCI-E 20: 00000000 [ 3222.583893] EEH: PCI-E AER capability register set follows:
[ 3222.584079] EEH: PCI-E AER 00: 13c10001 00000000 00000000 00062030 [ 3222.584230] EEH: PCI-E AER 10: 00002000 000031c0 000001e0 00000000 [ 3222.584378] EEH: PCI-E AER 20: 00000000 00000000 00000000 00000000 [ 3222.584416] EEH: PCI-E AER 30: 00000000 00000000 [ 3222.584416] EEH: of node=0384:80:00.1 [ 3222.584454] EEH: PCI device/vendor: 168e14e4 [ 3222.584491] EEH: PCI cmd/status register: 00100140 [ 3222.584492] EEH: PCI-E capabilities and status follow:
[ 3222.584677] EEH: PCI-E 00: 00020010 012c8da2 00095d5e 00455c82 [ 3222.584825] EEH: PCI-E 10: 10820000 00000000 00000000 00000000 [ 3222.584826] EEH: PCI-E 20: 00000000 [ 3222.584826] EEH: PCI-E AER capability register set follows:
[ 3222.585011] EEH: PCI-E AER 00: 13c10001 00000000 00000000 00062030 [ 3222.585160] EEH: PCI-E AER 10: 00002000 000031c0 000001e0 00000000 [ 3222.585309] EEH: PCI-E AER 20: 00000000 00000000 00000000 00000000 [ 3222.585347] EEH: PCI-E AER 30: 00000000 00000000 [ 3222.586872] RTAS: event: 5, Type: Platform Error (224), Severity: 2 [ 3222.586873] EEH: Reset without hotplug activity [ 3224.762767] EEH: Beginning: 'slot_reset'
[ 3224.762770] EEH: PE#800000 (PCI 0384:80:00.0): Invoking
bnx2x->slot_reset()
[ 3224.762771] bnx2x: [bnx2x_io_slot_reset:14271(eth14)]IO slot reset initializing...
[ 3224.762887] bnx2x 0384:80:00.0: enabling device (0140 -> 0142) [ 3224.768157] bnx2x: [bnx2x_io_slot_reset:14287(eth14)]IO slot reset
--> driver unload

Uninterruptible tasks
=====================
crash> ps | grep UN
     213      2  11  c000000004c89e00  UN   0.0       0      0  [eehd]
     215      2   0  c000000004c80000  UN   0.0       0      0
[kworker/0:2]
    2196      1  28  c000000004504f00  UN   0.1   15936  11136  wickedd
    4287      1   9  c00000020d076800  UN   0.0    4032   3008  agetty
    4289      1  20  c00000020d056680  UN   0.0    7232   3840  agetty
   32423      2  26  c00000020038c580  UN   0.0       0      0
[kworker/26:3]
   32871   4241  27  c0000002609ddd00  UN   0.1   18624  11648  sshd
   32920  10130  16  c00000027284a100  UN   0.1   48512  12608  sendmail
   33092  32987   0  c000000205218b00  UN   0.1   48512  12608  sendmail
   33154   4567  16  c000000260e51780  UN   0.1   48832  12864  pickup
   33209   4241  36  c000000270cb6500  UN   0.1   18624  11712  sshd
   33473  33283   0  c000000205211480  UN   0.1   48512  12672  sendmail
   33531   4241  37  c00000023c902780  UN   0.1   18624  11648  sshd

EEH handler hung while bnx2x sleeping and holding RTNL lock
===========================================================
crash> bt 213
PID: 213    TASK: c000000004c89e00  CPU: 11  COMMAND: "eehd"
  #0 [c000000004d477e0] __schedule at c000000000c70808
  #1 [c000000004d478b0] schedule at c000000000c70ee0
  #2 [c000000004d478e0] schedule_timeout at c000000000c76dec
  #3 [c000000004d479c0] msleep at c0000000002120cc
  #4 [c000000004d479f0] napi_disable at c000000000a06448
                                        ^^^^^^^^^^^^^^^^
  #5 [c000000004d47a30] bnx2x_netif_stop at c0080000018dba94 [bnx2x]
  #6 [c000000004d47a60] bnx2x_io_slot_reset at c0080000018a551c [bnx2x]
  #7 [c000000004d47b20] eeh_report_reset at c00000000004c9bc
  #8 [c000000004d47b90] eeh_pe_report at c00000000004d1a8
  #9 [c000000004d47c40] eeh_handle_normal_event at c00000000004da64

And the sleeping source code
============================
crash> dis -ls c000000000a06448
FILE: ../net/core/dev.c
LINE: 6702

   6697  {
   6698          might_sleep();
   6699          set_bit(NAPI_STATE_DISABLE, &n->state);
   6700
   6701          while (test_and_set_bit(NAPI_STATE_SCHED, &n->state))
* 6702                  msleep(1);
   6703          while (test_and_set_bit(NAPI_STATE_NPSVC, &n->state))
   6704                  msleep(1);
   6705
   6706          hrtimer_cancel(&n->timer);
   6707
   6708          clear_bit(NAPI_STATE_DISABLE, &n->state);
   6709  }

EEH calls into bnx2x twice based on the system log above, first through
bnx2x_io_error_detected() and then bnx2x_io_slot_reset(), and executes
the following call chains:

bnx2x_io_error_detected()
  +-> bnx2x_eeh_nic_unload()
       +-> bnx2x_del_all_napi()
            +-> __netif_napi_del()

bnx2x_io_slot_reset()
  +-> bnx2x_netif_stop()
       +-> bnx2x_napi_disable()
            +->napi_disable()

Fix this by correcting the sequence of NAPI APIs usage,
that is delete the NAPI after disabling it.

Fixes: 7fa6f34 ("bnx2x: AER revised")
Reported-by: David Christensen <[email protected]>
Tested-by: David Christensen <[email protected]>
Signed-off-by: Manish Chopra <[email protected]>
Signed-off-by: Ariel Elior <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
dreibh pushed a commit to dreibh/mptcp that referenced this issue May 19, 2022
commit 91a7cda1f4b8bdf770000a3b60640576dafe0cec upstream.

This fixes the following error caused by a race condition between
phydev->adjust_link() and a MDIO transaction in the phy interrupt
handler. The issue was reproduced with the ethernet FEC driver and a
micrel KSZ9031 phy.

[  146.195696] fec 2188000.ethernet eth0: MDIO read timeout
[  146.201779] ------------[ cut here ]------------
[  146.206671] WARNING: CPU: 0 PID: 571 at drivers/net/phy/phy.c:942 phy_error+0x24/0x6c
[  146.214744] Modules linked in: bnep imx_vdoa imx_sdma evbug
[  146.220640] CPU: 0 PID: 571 Comm: irq/128-2188000 Not tainted 5.18.0-rc3-00080-gd569e86915b7 multipath-tcp#9
[  146.229563] Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
[  146.236257]  unwind_backtrace from show_stack+0x10/0x14
[  146.241640]  show_stack from dump_stack_lvl+0x58/0x70
[  146.246841]  dump_stack_lvl from __warn+0xb4/0x24c
[  146.251772]  __warn from warn_slowpath_fmt+0x5c/0xd4
[  146.256873]  warn_slowpath_fmt from phy_error+0x24/0x6c
[  146.262249]  phy_error from kszphy_handle_interrupt+0x40/0x48
[  146.268159]  kszphy_handle_interrupt from irq_thread_fn+0x1c/0x78
[  146.274417]  irq_thread_fn from irq_thread+0xf0/0x1dc
[  146.279605]  irq_thread from kthread+0xe4/0x104
[  146.284267]  kthread from ret_from_fork+0x14/0x28
[  146.289164] Exception stack(0xe6fa1fb0 to 0xe6fa1ff8)
[  146.294448] 1fa0:                                     00000000 00000000 00000000 00000000
[  146.302842] 1fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[  146.311281] 1fe0: 00000000 00000000 00000000 00000000 00000013 00000000
[  146.318262] irq event stamp: 12325
[  146.321780] hardirqs last  enabled at (12333): [<c01984c4>] __up_console_sem+0x50/0x60
[  146.330013] hardirqs last disabled at (12342): [<c01984b0>] __up_console_sem+0x3c/0x60
[  146.338259] softirqs last  enabled at (12324): [<c01017f0>] __do_softirq+0x2c0/0x624
[  146.346311] softirqs last disabled at (12319): [<c01300ac>] __irq_exit_rcu+0x138/0x178
[  146.354447] ---[ end trace 0000000000000000 ]---

With the FEC driver phydev->adjust_link() calls fec_enet_adjust_link()
calls fec_stop()/fec_restart() and both these function reset and
temporary disable the FEC disrupting any MII transaction that
could be happening at the same time.

fec_enet_adjust_link() and phy_read() can be running at the same time
when we have one additional interrupt before the phy_state_machine() is
able to terminate.

Thread 1 (phylib WQ)       | Thread 2 (phy interrupt)
                           |
                           | phy_interrupt()            <-- PHY IRQ
                           |  handle_interrupt()
                           |   phy_read()
                           |   phy_trigger_machine()
                           |    --> schedule phylib WQ
                           |
                           |
phy_state_machine()        |
 phy_check_link_status()   |
  phy_link_change()        |
   phydev->adjust_link()   |
    fec_enet_adjust_link() |
     --> FEC reset         | phy_interrupt()            <-- PHY IRQ
                           |  phy_read()
                           |

Fix this by acquiring the phydev lock in phy_interrupt().

Link: https://lore.kernel.org/all/[email protected]/
Fixes: c974bdb ("net: phy: Use threaded IRQ, to allow IRQ from sleeping devices")
cc: <[email protected]>
Signed-off-by: Francesco Dolcini <[email protected]>
Reviewed-by: Andrew Lunn <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
[fd: backport: adapt locking before did_interrupt()/ack_interrupt()
 callbacks removal ]
Signed-off-by: Francesco Dolcini <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
matttbe pushed a commit that referenced this issue Jul 1, 2022
commit 42252d0d2aa9b94d168241710a761588b3959019 upstream.

This patch fixes an invalid read showed by KASAN. A unlock will allocate a
"struct plock_op" and a followed send_op() will append it to a global
send_list data structure. In some cases a followed dev_read() moves it
to recv_list and dev_write() will cast it to "struct plock_xop" and access
fields which are only available in those structures. At this point an
invalid read happens by accessing those fields.

To fix this issue the "callback" field is moved to "struct plock_op" to
indicate that a cast to "plock_xop" is allowed and does the additional
"plock_xop" handling if set.

Example of the KASAN output which showed the invalid read:

[ 2064.296453] ==================================================================
[ 2064.304852] BUG: KASAN: slab-out-of-bounds in dev_write+0x52b/0x5a0 [dlm]
[ 2064.306491] Read of size 8 at addr ffff88800ef227d8 by task dlm_controld/7484
[ 2064.308168]
[ 2064.308575] CPU: 0 PID: 7484 Comm: dlm_controld Kdump: loaded Not tainted 5.14.0+ #9
[ 2064.310292] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
[ 2064.311618] Call Trace:
[ 2064.312218]  dump_stack_lvl+0x56/0x7b
[ 2064.313150]  print_address_description.constprop.8+0x21/0x150
[ 2064.314578]  ? dev_write+0x52b/0x5a0 [dlm]
[ 2064.315610]  ? dev_write+0x52b/0x5a0 [dlm]
[ 2064.316595]  kasan_report.cold.14+0x7f/0x11b
[ 2064.317674]  ? dev_write+0x52b/0x5a0 [dlm]
[ 2064.318687]  dev_write+0x52b/0x5a0 [dlm]
[ 2064.319629]  ? dev_read+0x4a0/0x4a0 [dlm]
[ 2064.320713]  ? bpf_lsm_kernfs_init_security+0x10/0x10
[ 2064.321926]  vfs_write+0x17e/0x930
[ 2064.322769]  ? __fget_light+0x1aa/0x220
[ 2064.323753]  ksys_write+0xf1/0x1c0
[ 2064.324548]  ? __ia32_sys_read+0xb0/0xb0
[ 2064.325464]  do_syscall_64+0x3a/0x80
[ 2064.326387]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 2064.327606] RIP: 0033:0x7f807e4ba96f
[ 2064.328470] Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 39 87 f8 ff 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 7c 87 f8 ff 48
[ 2064.332902] RSP: 002b:00007ffd50cfe6e0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
[ 2064.334658] RAX: ffffffffffffffda RBX: 000055cc3886eb30 RCX: 00007f807e4ba96f
[ 2064.336275] RDX: 0000000000000040 RSI: 00007ffd50cfe7e0 RDI: 0000000000000010
[ 2064.337980] RBP: 00007ffd50cfe7e0 R08: 0000000000000000 R09: 0000000000000001
[ 2064.339560] R10: 000055cc3886eb30 R11: 0000000000000293 R12: 000055cc3886eb80
[ 2064.341237] R13: 000055cc3886eb00 R14: 000055cc3886f590 R15: 0000000000000001
[ 2064.342857]
[ 2064.343226] Allocated by task 12438:
[ 2064.344057]  kasan_save_stack+0x1c/0x40
[ 2064.345079]  __kasan_kmalloc+0x84/0xa0
[ 2064.345933]  kmem_cache_alloc_trace+0x13b/0x220
[ 2064.346953]  dlm_posix_unlock+0xec/0x720 [dlm]
[ 2064.348811]  do_lock_file_wait.part.32+0xca/0x1d0
[ 2064.351070]  fcntl_setlk+0x281/0xbc0
[ 2064.352879]  do_fcntl+0x5e4/0xfe0
[ 2064.354657]  __x64_sys_fcntl+0x11f/0x170
[ 2064.356550]  do_syscall_64+0x3a/0x80
[ 2064.358259]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 2064.360745]
[ 2064.361511] Last potentially related work creation:
[ 2064.363957]  kasan_save_stack+0x1c/0x40
[ 2064.365811]  __kasan_record_aux_stack+0xaf/0xc0
[ 2064.368100]  call_rcu+0x11b/0xf70
[ 2064.369785]  dlm_process_incoming_buffer+0x47d/0xfd0 [dlm]
[ 2064.372404]  receive_from_sock+0x290/0x770 [dlm]
[ 2064.374607]  process_recv_sockets+0x32/0x40 [dlm]
[ 2064.377290]  process_one_work+0x9a8/0x16e0
[ 2064.379357]  worker_thread+0x87/0xbf0
[ 2064.381188]  kthread+0x3ac/0x490
[ 2064.383460]  ret_from_fork+0x22/0x30
[ 2064.385588]
[ 2064.386518] Second to last potentially related work creation:
[ 2064.389219]  kasan_save_stack+0x1c/0x40
[ 2064.391043]  __kasan_record_aux_stack+0xaf/0xc0
[ 2064.393303]  call_rcu+0x11b/0xf70
[ 2064.394885]  dlm_process_incoming_buffer+0x47d/0xfd0 [dlm]
[ 2064.397694]  receive_from_sock+0x290/0x770 [dlm]
[ 2064.399932]  process_recv_sockets+0x32/0x40 [dlm]
[ 2064.402180]  process_one_work+0x9a8/0x16e0
[ 2064.404388]  worker_thread+0x87/0xbf0
[ 2064.406124]  kthread+0x3ac/0x490
[ 2064.408021]  ret_from_fork+0x22/0x30
[ 2064.409834]
[ 2064.410599] The buggy address belongs to the object at ffff88800ef22780
[ 2064.410599]  which belongs to the cache kmalloc-96 of size 96
[ 2064.416495] The buggy address is located 88 bytes inside of
[ 2064.416495]  96-byte region [ffff88800ef22780, ffff88800ef227e0)
[ 2064.422045] The buggy address belongs to the page:
[ 2064.424635] page:00000000b6bef8bc refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xef22
[ 2064.428970] flags: 0xfffffc0000200(slab|node=0|zone=1|lastcpupid=0x1fffff)
[ 2064.432515] raw: 000fffffc0000200 ffffea0000d68b80 0000001400000014 ffff888001041780
[ 2064.436110] raw: 0000000000000000 0000000080200020 00000001ffffffff 0000000000000000
[ 2064.439813] page dumped because: kasan: bad access detected
[ 2064.442548]
[ 2064.443310] Memory state around the buggy address:
[ 2064.445988]  ffff88800ef22680: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
[ 2064.449444]  ffff88800ef22700: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
[ 2064.452941] >ffff88800ef22780: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc
[ 2064.456383]                                                     ^
[ 2064.459386]  ffff88800ef22800: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc
[ 2064.462788]  ffff88800ef22880: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
[ 2064.466239] ==================================================================

reproducer in python:

import argparse
import struct
import fcntl
import os

parser = argparse.ArgumentParser()

parser.add_argument('-f', '--file',
		    help='file to use fcntl, must be on dlm lock filesystem e.g. gfs2')

args = parser.parse_args()

f = open(args.file, 'wb+')

lockdata = struct.pack('hhllhh', fcntl.F_WRLCK,0,0,0,0,0)
fcntl.fcntl(f, fcntl.F_SETLK, lockdata)
lockdata = struct.pack('hhllhh', fcntl.F_UNLCK,0,0,0,0,0)
fcntl.fcntl(f, fcntl.F_SETLK, lockdata)

Fixes: 586759f ("gfs2: nfs lock support for gfs2")
Cc: [email protected]
Signed-off-by: Andreas Gruenbacher <[email protected]>
Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David Teigland <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
matttbe pushed a commit that referenced this issue Jul 1, 2022
commit 42252d0d2aa9b94d168241710a761588b3959019 upstream.

This patch fixes an invalid read showed by KASAN. A unlock will allocate a
"struct plock_op" and a followed send_op() will append it to a global
send_list data structure. In some cases a followed dev_read() moves it
to recv_list and dev_write() will cast it to "struct plock_xop" and access
fields which are only available in those structures. At this point an
invalid read happens by accessing those fields.

To fix this issue the "callback" field is moved to "struct plock_op" to
indicate that a cast to "plock_xop" is allowed and does the additional
"plock_xop" handling if set.

Example of the KASAN output which showed the invalid read:

[ 2064.296453] ==================================================================
[ 2064.304852] BUG: KASAN: slab-out-of-bounds in dev_write+0x52b/0x5a0 [dlm]
[ 2064.306491] Read of size 8 at addr ffff88800ef227d8 by task dlm_controld/7484
[ 2064.308168]
[ 2064.308575] CPU: 0 PID: 7484 Comm: dlm_controld Kdump: loaded Not tainted 5.14.0+ #9
[ 2064.310292] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
[ 2064.311618] Call Trace:
[ 2064.312218]  dump_stack_lvl+0x56/0x7b
[ 2064.313150]  print_address_description.constprop.8+0x21/0x150
[ 2064.314578]  ? dev_write+0x52b/0x5a0 [dlm]
[ 2064.315610]  ? dev_write+0x52b/0x5a0 [dlm]
[ 2064.316595]  kasan_report.cold.14+0x7f/0x11b
[ 2064.317674]  ? dev_write+0x52b/0x5a0 [dlm]
[ 2064.318687]  dev_write+0x52b/0x5a0 [dlm]
[ 2064.319629]  ? dev_read+0x4a0/0x4a0 [dlm]
[ 2064.320713]  ? bpf_lsm_kernfs_init_security+0x10/0x10
[ 2064.321926]  vfs_write+0x17e/0x930
[ 2064.322769]  ? __fget_light+0x1aa/0x220
[ 2064.323753]  ksys_write+0xf1/0x1c0
[ 2064.324548]  ? __ia32_sys_read+0xb0/0xb0
[ 2064.325464]  do_syscall_64+0x3a/0x80
[ 2064.326387]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 2064.327606] RIP: 0033:0x7f807e4ba96f
[ 2064.328470] Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 39 87 f8 ff 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 7c 87 f8 ff 48
[ 2064.332902] RSP: 002b:00007ffd50cfe6e0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
[ 2064.334658] RAX: ffffffffffffffda RBX: 000055cc3886eb30 RCX: 00007f807e4ba96f
[ 2064.336275] RDX: 0000000000000040 RSI: 00007ffd50cfe7e0 RDI: 0000000000000010
[ 2064.337980] RBP: 00007ffd50cfe7e0 R08: 0000000000000000 R09: 0000000000000001
[ 2064.339560] R10: 000055cc3886eb30 R11: 0000000000000293 R12: 000055cc3886eb80
[ 2064.341237] R13: 000055cc3886eb00 R14: 000055cc3886f590 R15: 0000000000000001
[ 2064.342857]
[ 2064.343226] Allocated by task 12438:
[ 2064.344057]  kasan_save_stack+0x1c/0x40
[ 2064.345079]  __kasan_kmalloc+0x84/0xa0
[ 2064.345933]  kmem_cache_alloc_trace+0x13b/0x220
[ 2064.346953]  dlm_posix_unlock+0xec/0x720 [dlm]
[ 2064.348811]  do_lock_file_wait.part.32+0xca/0x1d0
[ 2064.351070]  fcntl_setlk+0x281/0xbc0
[ 2064.352879]  do_fcntl+0x5e4/0xfe0
[ 2064.354657]  __x64_sys_fcntl+0x11f/0x170
[ 2064.356550]  do_syscall_64+0x3a/0x80
[ 2064.358259]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 2064.360745]
[ 2064.361511] Last potentially related work creation:
[ 2064.363957]  kasan_save_stack+0x1c/0x40
[ 2064.365811]  __kasan_record_aux_stack+0xaf/0xc0
[ 2064.368100]  call_rcu+0x11b/0xf70
[ 2064.369785]  dlm_process_incoming_buffer+0x47d/0xfd0 [dlm]
[ 2064.372404]  receive_from_sock+0x290/0x770 [dlm]
[ 2064.374607]  process_recv_sockets+0x32/0x40 [dlm]
[ 2064.377290]  process_one_work+0x9a8/0x16e0
[ 2064.379357]  worker_thread+0x87/0xbf0
[ 2064.381188]  kthread+0x3ac/0x490
[ 2064.383460]  ret_from_fork+0x22/0x30
[ 2064.385588]
[ 2064.386518] Second to last potentially related work creation:
[ 2064.389219]  kasan_save_stack+0x1c/0x40
[ 2064.391043]  __kasan_record_aux_stack+0xaf/0xc0
[ 2064.393303]  call_rcu+0x11b/0xf70
[ 2064.394885]  dlm_process_incoming_buffer+0x47d/0xfd0 [dlm]
[ 2064.397694]  receive_from_sock+0x290/0x770 [dlm]
[ 2064.399932]  process_recv_sockets+0x32/0x40 [dlm]
[ 2064.402180]  process_one_work+0x9a8/0x16e0
[ 2064.404388]  worker_thread+0x87/0xbf0
[ 2064.406124]  kthread+0x3ac/0x490
[ 2064.408021]  ret_from_fork+0x22/0x30
[ 2064.409834]
[ 2064.410599] The buggy address belongs to the object at ffff88800ef22780
[ 2064.410599]  which belongs to the cache kmalloc-96 of size 96
[ 2064.416495] The buggy address is located 88 bytes inside of
[ 2064.416495]  96-byte region [ffff88800ef22780, ffff88800ef227e0)
[ 2064.422045] The buggy address belongs to the page:
[ 2064.424635] page:00000000b6bef8bc refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xef22
[ 2064.428970] flags: 0xfffffc0000200(slab|node=0|zone=1|lastcpupid=0x1fffff)
[ 2064.432515] raw: 000fffffc0000200 ffffea0000d68b80 0000001400000014 ffff888001041780
[ 2064.436110] raw: 0000000000000000 0000000080200020 00000001ffffffff 0000000000000000
[ 2064.439813] page dumped because: kasan: bad access detected
[ 2064.442548]
[ 2064.443310] Memory state around the buggy address:
[ 2064.445988]  ffff88800ef22680: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
[ 2064.449444]  ffff88800ef22700: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
[ 2064.452941] >ffff88800ef22780: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc
[ 2064.456383]                                                     ^
[ 2064.459386]  ffff88800ef22800: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc
[ 2064.462788]  ffff88800ef22880: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
[ 2064.466239] ==================================================================

reproducer in python:

import argparse
import struct
import fcntl
import os

parser = argparse.ArgumentParser()

parser.add_argument('-f', '--file',
		    help='file to use fcntl, must be on dlm lock filesystem e.g. gfs2')

args = parser.parse_args()

f = open(args.file, 'wb+')

lockdata = struct.pack('hhllhh', fcntl.F_WRLCK,0,0,0,0,0)
fcntl.fcntl(f, fcntl.F_SETLK, lockdata)
lockdata = struct.pack('hhllhh', fcntl.F_UNLCK,0,0,0,0,0)
fcntl.fcntl(f, fcntl.F_SETLK, lockdata)

Fixes: 586759f ("gfs2: nfs lock support for gfs2")
Cc: [email protected]
Signed-off-by: Andreas Gruenbacher <[email protected]>
Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David Teigland <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
matttbe pushed a commit that referenced this issue Jul 1, 2022
commit 42252d0d2aa9b94d168241710a761588b3959019 upstream.

This patch fixes an invalid read showed by KASAN. A unlock will allocate a
"struct plock_op" and a followed send_op() will append it to a global
send_list data structure. In some cases a followed dev_read() moves it
to recv_list and dev_write() will cast it to "struct plock_xop" and access
fields which are only available in those structures. At this point an
invalid read happens by accessing those fields.

To fix this issue the "callback" field is moved to "struct plock_op" to
indicate that a cast to "plock_xop" is allowed and does the additional
"plock_xop" handling if set.

Example of the KASAN output which showed the invalid read:

[ 2064.296453] ==================================================================
[ 2064.304852] BUG: KASAN: slab-out-of-bounds in dev_write+0x52b/0x5a0 [dlm]
[ 2064.306491] Read of size 8 at addr ffff88800ef227d8 by task dlm_controld/7484
[ 2064.308168]
[ 2064.308575] CPU: 0 PID: 7484 Comm: dlm_controld Kdump: loaded Not tainted 5.14.0+ #9
[ 2064.310292] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
[ 2064.311618] Call Trace:
[ 2064.312218]  dump_stack_lvl+0x56/0x7b
[ 2064.313150]  print_address_description.constprop.8+0x21/0x150
[ 2064.314578]  ? dev_write+0x52b/0x5a0 [dlm]
[ 2064.315610]  ? dev_write+0x52b/0x5a0 [dlm]
[ 2064.316595]  kasan_report.cold.14+0x7f/0x11b
[ 2064.317674]  ? dev_write+0x52b/0x5a0 [dlm]
[ 2064.318687]  dev_write+0x52b/0x5a0 [dlm]
[ 2064.319629]  ? dev_read+0x4a0/0x4a0 [dlm]
[ 2064.320713]  ? bpf_lsm_kernfs_init_security+0x10/0x10
[ 2064.321926]  vfs_write+0x17e/0x930
[ 2064.322769]  ? __fget_light+0x1aa/0x220
[ 2064.323753]  ksys_write+0xf1/0x1c0
[ 2064.324548]  ? __ia32_sys_read+0xb0/0xb0
[ 2064.325464]  do_syscall_64+0x3a/0x80
[ 2064.326387]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 2064.327606] RIP: 0033:0x7f807e4ba96f
[ 2064.328470] Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 39 87 f8 ff 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 7c 87 f8 ff 48
[ 2064.332902] RSP: 002b:00007ffd50cfe6e0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
[ 2064.334658] RAX: ffffffffffffffda RBX: 000055cc3886eb30 RCX: 00007f807e4ba96f
[ 2064.336275] RDX: 0000000000000040 RSI: 00007ffd50cfe7e0 RDI: 0000000000000010
[ 2064.337980] RBP: 00007ffd50cfe7e0 R08: 0000000000000000 R09: 0000000000000001
[ 2064.339560] R10: 000055cc3886eb30 R11: 0000000000000293 R12: 000055cc3886eb80
[ 2064.341237] R13: 000055cc3886eb00 R14: 000055cc3886f590 R15: 0000000000000001
[ 2064.342857]
[ 2064.343226] Allocated by task 12438:
[ 2064.344057]  kasan_save_stack+0x1c/0x40
[ 2064.345079]  __kasan_kmalloc+0x84/0xa0
[ 2064.345933]  kmem_cache_alloc_trace+0x13b/0x220
[ 2064.346953]  dlm_posix_unlock+0xec/0x720 [dlm]
[ 2064.348811]  do_lock_file_wait.part.32+0xca/0x1d0
[ 2064.351070]  fcntl_setlk+0x281/0xbc0
[ 2064.352879]  do_fcntl+0x5e4/0xfe0
[ 2064.354657]  __x64_sys_fcntl+0x11f/0x170
[ 2064.356550]  do_syscall_64+0x3a/0x80
[ 2064.358259]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 2064.360745]
[ 2064.361511] Last potentially related work creation:
[ 2064.363957]  kasan_save_stack+0x1c/0x40
[ 2064.365811]  __kasan_record_aux_stack+0xaf/0xc0
[ 2064.368100]  call_rcu+0x11b/0xf70
[ 2064.369785]  dlm_process_incoming_buffer+0x47d/0xfd0 [dlm]
[ 2064.372404]  receive_from_sock+0x290/0x770 [dlm]
[ 2064.374607]  process_recv_sockets+0x32/0x40 [dlm]
[ 2064.377290]  process_one_work+0x9a8/0x16e0
[ 2064.379357]  worker_thread+0x87/0xbf0
[ 2064.381188]  kthread+0x3ac/0x490
[ 2064.383460]  ret_from_fork+0x22/0x30
[ 2064.385588]
[ 2064.386518] Second to last potentially related work creation:
[ 2064.389219]  kasan_save_stack+0x1c/0x40
[ 2064.391043]  __kasan_record_aux_stack+0xaf/0xc0
[ 2064.393303]  call_rcu+0x11b/0xf70
[ 2064.394885]  dlm_process_incoming_buffer+0x47d/0xfd0 [dlm]
[ 2064.397694]  receive_from_sock+0x290/0x770 [dlm]
[ 2064.399932]  process_recv_sockets+0x32/0x40 [dlm]
[ 2064.402180]  process_one_work+0x9a8/0x16e0
[ 2064.404388]  worker_thread+0x87/0xbf0
[ 2064.406124]  kthread+0x3ac/0x490
[ 2064.408021]  ret_from_fork+0x22/0x30
[ 2064.409834]
[ 2064.410599] The buggy address belongs to the object at ffff88800ef22780
[ 2064.410599]  which belongs to the cache kmalloc-96 of size 96
[ 2064.416495] The buggy address is located 88 bytes inside of
[ 2064.416495]  96-byte region [ffff88800ef22780, ffff88800ef227e0)
[ 2064.422045] The buggy address belongs to the page:
[ 2064.424635] page:00000000b6bef8bc refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xef22
[ 2064.428970] flags: 0xfffffc0000200(slab|node=0|zone=1|lastcpupid=0x1fffff)
[ 2064.432515] raw: 000fffffc0000200 ffffea0000d68b80 0000001400000014 ffff888001041780
[ 2064.436110] raw: 0000000000000000 0000000080200020 00000001ffffffff 0000000000000000
[ 2064.439813] page dumped because: kasan: bad access detected
[ 2064.442548]
[ 2064.443310] Memory state around the buggy address:
[ 2064.445988]  ffff88800ef22680: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
[ 2064.449444]  ffff88800ef22700: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
[ 2064.452941] >ffff88800ef22780: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc
[ 2064.456383]                                                     ^
[ 2064.459386]  ffff88800ef22800: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc
[ 2064.462788]  ffff88800ef22880: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
[ 2064.466239] ==================================================================

reproducer in python:

import argparse
import struct
import fcntl
import os

parser = argparse.ArgumentParser()

parser.add_argument('-f', '--file',
		    help='file to use fcntl, must be on dlm lock filesystem e.g. gfs2')

args = parser.parse_args()

f = open(args.file, 'wb+')

lockdata = struct.pack('hhllhh', fcntl.F_WRLCK,0,0,0,0,0)
fcntl.fcntl(f, fcntl.F_SETLK, lockdata)
lockdata = struct.pack('hhllhh', fcntl.F_UNLCK,0,0,0,0,0)
fcntl.fcntl(f, fcntl.F_SETLK, lockdata)

Fixes: 586759f ("gfs2: nfs lock support for gfs2")
Cc: [email protected]
Signed-off-by: Andreas Gruenbacher <[email protected]>
Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David Teigland <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
matttbe pushed a commit that referenced this issue Jan 25, 2023
…g the sock

[ Upstream commit 3cf7203ca620682165706f70a1b12b5194607dce ]

There is a race condition in vxlan that when deleting a vxlan device
during receiving packets, there is a possibility that the sock is
released after getting vxlan_sock vs from sk_user_data. Then in
later vxlan_ecn_decapsulate(), vxlan_get_sk_family() we will got
NULL pointer dereference. e.g.

   #0 [ffffa25ec6978a38] machine_kexec at ffffffff8c669757
   #1 [ffffa25ec6978a90] __crash_kexec at ffffffff8c7c0a4d
   #2 [ffffa25ec6978b58] crash_kexec at ffffffff8c7c1c48
   #3 [ffffa25ec6978b60] oops_end at ffffffff8c627f2b
   #4 [ffffa25ec6978b80] page_fault_oops at ffffffff8c678fcb
   #5 [ffffa25ec6978bd8] exc_page_fault at ffffffff8d109542
   #6 [ffffa25ec6978c00] asm_exc_page_fault at ffffffff8d200b62
      [exception RIP: vxlan_ecn_decapsulate+0x3b]
      RIP: ffffffffc1014e7b  RSP: ffffa25ec6978cb0  RFLAGS: 00010246
      RAX: 0000000000000008  RBX: ffff8aa000888000  RCX: 0000000000000000
      RDX: 000000000000000e  RSI: ffff8a9fc7ab803e  RDI: ffff8a9fd1168700
      RBP: ffff8a9fc7ab803e   R8: 0000000000700000   R9: 00000000000010ae
      R10: ffff8a9fcb748980  R11: 0000000000000000  R12: ffff8a9fd1168700
      R13: ffff8aa000888000  R14: 00000000002a0000  R15: 00000000000010ae
      ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
   #7 [ffffa25ec6978ce8] vxlan_rcv at ffffffffc10189cd [vxlan]
   #8 [ffffa25ec6978d90] udp_queue_rcv_one_skb at ffffffff8cfb6507
   #9 [ffffa25ec6978dc0] udp_unicast_rcv_skb at ffffffff8cfb6e45
  #10 [ffffa25ec6978dc8] __udp4_lib_rcv at ffffffff8cfb8807
  #11 [ffffa25ec6978e20] ip_protocol_deliver_rcu at ffffffff8cf76951
  #12 [ffffa25ec6978e48] ip_local_deliver at ffffffff8cf76bde
  #13 [ffffa25ec6978ea0] __netif_receive_skb_one_core at ffffffff8cecde9b
  #14 [ffffa25ec6978ec8] process_backlog at ffffffff8cece139
  #15 [ffffa25ec6978f00] __napi_poll at ffffffff8ceced1a
  #16 [ffffa25ec6978f28] net_rx_action at ffffffff8cecf1f3
  #17 [ffffa25ec6978fa0] __softirqentry_text_start at ffffffff8d4000ca
  #18 [ffffa25ec6978ff0] do_softirq at ffffffff8c6fbdc3

Reproducer: https://github.com/Mellanox/ovs-tests/blob/master/test-ovs-vxlan-remove-tunnel-during-traffic.sh

Fix this by waiting for all sk_user_data reader to finish before
releasing the sock.

Reported-by: Jianlin Shi <[email protected]>
Suggested-by: Jakub Sitnicki <[email protected]>
Fixes: 6a93cc9 ("udp-tunnel: Add a few more UDP tunnel APIs")
Signed-off-by: Hangbin Liu <[email protected]>
Reviewed-by: Jiri Pirko <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
matttbe pushed a commit that referenced this issue Jan 25, 2023
[ Upstream commit 6c606e57eecc37d6b36d732b1ff7e55b7dc32dd4 ]

It's unsafe to use rtas_busy_delay() to handle a busy status from
the ibm,os-term RTAS function in rtas_os_term():

Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
BUG: sleeping function called from invalid context at arch/powerpc/kernel/rtas.c:618
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 1, name: swapper/0
preempt_count: 2, expected: 0
CPU: 7 PID: 1 Comm: swapper/0 Tainted: G      D            6.0.0-rc5-02182-gf8553a572277-dirty #9
Call Trace:
[c000000007b8f000] [c000000001337110] dump_stack_lvl+0xb4/0x110 (unreliable)
[c000000007b8f040] [c0000000002440e4] __might_resched+0x394/0x3c0
[c000000007b8f0e0] [c00000000004f680] rtas_busy_delay+0x120/0x1b0
[c000000007b8f100] [c000000000052d04] rtas_os_term+0xb8/0xf4
[c000000007b8f180] [c0000000001150fc] pseries_panic+0x50/0x68
[c000000007b8f1f0] [c000000000036354] ppc_panic_platform_handler+0x34/0x50
[c000000007b8f210] [c0000000002303c4] notifier_call_chain+0xd4/0x1c0
[c000000007b8f2b0] [c0000000002306cc] atomic_notifier_call_chain+0xac/0x1c0
[c000000007b8f2f0] [c0000000001d62b8] panic+0x228/0x4d0
[c000000007b8f390] [c0000000001e573c] do_exit+0x140c/0x1420
[c000000007b8f480] [c0000000001e586c] make_task_dead+0xdc/0x200

Use rtas_busy_delay_time() instead, which signals without side effects
whether to attempt the ibm,os-term RTAS call again.

Signed-off-by: Nathan Lynch <[email protected]>
Reviewed-by: Nicholas Piggin <[email protected]>
Reviewed-by: Andrew Donnellan <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Sasha Levin <[email protected]>
matttbe pushed a commit that referenced this issue Jan 25, 2023
[ Upstream commit b18cba09e374637a0a3759d856a6bca94c133952 ]

Commit 9130b8d ("SUNRPC: allow for upcalls for the same uid
but different gss service") introduced `auth` argument to
__gss_find_upcall(), but in gss_pipe_downcall() it was left as NULL
since it (and auth->service) was not (yet) determined.

When multiple upcalls with the same uid and different service are
ongoing, it could happen that __gss_find_upcall(), which returns the
first match found in the pipe->in_downcall list, could not find the
correct gss_msg corresponding to the downcall we are looking for.
Moreover, it might return a msg which is not sent to rpc.gssd yet.

We could see mount.nfs process hung in D state with multiple mount.nfs
are executed in parallel.  The call trace below is of CentOS 7.9
kernel-3.10.0-1160.24.1.el7.x86_64 but we observed the same hang w/
elrepo kernel-ml-6.0.7-1.el7.

PID: 71258  TASK: ffff91ebd4be0000  CPU: 36  COMMAND: "mount.nfs"
 #0 [ffff9203ca3234f8] __schedule at ffffffffa3b8899f
 #1 [ffff9203ca323580] schedule at ffffffffa3b88eb9
 #2 [ffff9203ca323590] gss_cred_init at ffffffffc0355818 [auth_rpcgss]
 #3 [ffff9203ca323658] rpcauth_lookup_credcache at ffffffffc0421ebc
[sunrpc]
 #4 [ffff9203ca3236d8] gss_lookup_cred at ffffffffc0353633 [auth_rpcgss]
 #5 [ffff9203ca3236e8] rpcauth_lookupcred at ffffffffc0421581 [sunrpc]
 #6 [ffff9203ca323740] rpcauth_refreshcred at ffffffffc04223d3 [sunrpc]
 #7 [ffff9203ca3237a0] call_refresh at ffffffffc04103dc [sunrpc]
 #8 [ffff9203ca3237b8] __rpc_execute at ffffffffc041e1c9 [sunrpc]
 #9 [ffff9203ca323820] rpc_execute at ffffffffc0420a48 [sunrpc]

The scenario is like this. Let's say there are two upcalls for
services A and B, A -> B in pipe->in_downcall, B -> A in pipe->pipe.

When rpc.gssd reads pipe to get the upcall msg corresponding to
service B from pipe->pipe and then writes the response, in
gss_pipe_downcall the msg corresponding to service A will be picked
because only uid is used to find the msg and it is before the one for
B in pipe->in_downcall.  And the process waiting for the msg
corresponding to service A will be woken up.

Actual scheduing of that process might be after rpc.gssd processes the
next msg.  In rpc_pipe_generic_upcall it clears msg->errno (for A).
The process is scheduled to see gss_msg->ctx == NULL and
gss_msg->msg.errno == 0, therefore it cannot break the loop in
gss_create_upcall and is never woken up after that.

This patch adds a simple check to ensure that a msg which is not
sent to rpc.gssd yet is not chosen as the matching upcall upon
receiving a downcall.

Signed-off-by: minoura makoto <[email protected]>
Signed-off-by: Hiroshi Shimamoto <[email protected]>
Tested-by: Hiroshi Shimamoto <[email protected]>
Cc: Trond Myklebust <[email protected]>
Fixes: 9130b8d ("SUNRPC: allow for upcalls for same uid but different gss service")
Signed-off-by: Trond Myklebust <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
matttbe pushed a commit that referenced this issue Jan 25, 2023
…g the sock

[ Upstream commit 3cf7203ca620682165706f70a1b12b5194607dce ]

There is a race condition in vxlan that when deleting a vxlan device
during receiving packets, there is a possibility that the sock is
released after getting vxlan_sock vs from sk_user_data. Then in
later vxlan_ecn_decapsulate(), vxlan_get_sk_family() we will got
NULL pointer dereference. e.g.

   #0 [ffffa25ec6978a38] machine_kexec at ffffffff8c669757
   #1 [ffffa25ec6978a90] __crash_kexec at ffffffff8c7c0a4d
   #2 [ffffa25ec6978b58] crash_kexec at ffffffff8c7c1c48
   #3 [ffffa25ec6978b60] oops_end at ffffffff8c627f2b
   #4 [ffffa25ec6978b80] page_fault_oops at ffffffff8c678fcb
   #5 [ffffa25ec6978bd8] exc_page_fault at ffffffff8d109542
   #6 [ffffa25ec6978c00] asm_exc_page_fault at ffffffff8d200b62
      [exception RIP: vxlan_ecn_decapsulate+0x3b]
      RIP: ffffffffc1014e7b  RSP: ffffa25ec6978cb0  RFLAGS: 00010246
      RAX: 0000000000000008  RBX: ffff8aa000888000  RCX: 0000000000000000
      RDX: 000000000000000e  RSI: ffff8a9fc7ab803e  RDI: ffff8a9fd1168700
      RBP: ffff8a9fc7ab803e   R8: 0000000000700000   R9: 00000000000010ae
      R10: ffff8a9fcb748980  R11: 0000000000000000  R12: ffff8a9fd1168700
      R13: ffff8aa000888000  R14: 00000000002a0000  R15: 00000000000010ae
      ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
   #7 [ffffa25ec6978ce8] vxlan_rcv at ffffffffc10189cd [vxlan]
   #8 [ffffa25ec6978d90] udp_queue_rcv_one_skb at ffffffff8cfb6507
   #9 [ffffa25ec6978dc0] udp_unicast_rcv_skb at ffffffff8cfb6e45
  #10 [ffffa25ec6978dc8] __udp4_lib_rcv at ffffffff8cfb8807
  #11 [ffffa25ec6978e20] ip_protocol_deliver_rcu at ffffffff8cf76951
  #12 [ffffa25ec6978e48] ip_local_deliver at ffffffff8cf76bde
  #13 [ffffa25ec6978ea0] __netif_receive_skb_one_core at ffffffff8cecde9b
  #14 [ffffa25ec6978ec8] process_backlog at ffffffff8cece139
  #15 [ffffa25ec6978f00] __napi_poll at ffffffff8ceced1a
  #16 [ffffa25ec6978f28] net_rx_action at ffffffff8cecf1f3
  #17 [ffffa25ec6978fa0] __softirqentry_text_start at ffffffff8d4000ca
  #18 [ffffa25ec6978ff0] do_softirq at ffffffff8c6fbdc3

Reproducer: https://github.com/Mellanox/ovs-tests/blob/master/test-ovs-vxlan-remove-tunnel-during-traffic.sh

Fix this by waiting for all sk_user_data reader to finish before
releasing the sock.

Reported-by: Jianlin Shi <[email protected]>
Suggested-by: Jakub Sitnicki <[email protected]>
Fixes: 6a93cc9 ("udp-tunnel: Add a few more UDP tunnel APIs")
Signed-off-by: Hangbin Liu <[email protected]>
Reviewed-by: Jiri Pirko <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
matttbe pushed a commit that referenced this issue Jan 25, 2023
[ Upstream commit 6c606e57eecc37d6b36d732b1ff7e55b7dc32dd4 ]

It's unsafe to use rtas_busy_delay() to handle a busy status from
the ibm,os-term RTAS function in rtas_os_term():

Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
BUG: sleeping function called from invalid context at arch/powerpc/kernel/rtas.c:618
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 1, name: swapper/0
preempt_count: 2, expected: 0
CPU: 7 PID: 1 Comm: swapper/0 Tainted: G      D            6.0.0-rc5-02182-gf8553a572277-dirty #9
Call Trace:
[c000000007b8f000] [c000000001337110] dump_stack_lvl+0xb4/0x110 (unreliable)
[c000000007b8f040] [c0000000002440e4] __might_resched+0x394/0x3c0
[c000000007b8f0e0] [c00000000004f680] rtas_busy_delay+0x120/0x1b0
[c000000007b8f100] [c000000000052d04] rtas_os_term+0xb8/0xf4
[c000000007b8f180] [c0000000001150fc] pseries_panic+0x50/0x68
[c000000007b8f1f0] [c000000000036354] ppc_panic_platform_handler+0x34/0x50
[c000000007b8f210] [c0000000002303c4] notifier_call_chain+0xd4/0x1c0
[c000000007b8f2b0] [c0000000002306cc] atomic_notifier_call_chain+0xac/0x1c0
[c000000007b8f2f0] [c0000000001d62b8] panic+0x228/0x4d0
[c000000007b8f390] [c0000000001e573c] do_exit+0x140c/0x1420
[c000000007b8f480] [c0000000001e586c] make_task_dead+0xdc/0x200

Use rtas_busy_delay_time() instead, which signals without side effects
whether to attempt the ibm,os-term RTAS call again.

Signed-off-by: Nathan Lynch <[email protected]>
Reviewed-by: Nicholas Piggin <[email protected]>
Reviewed-by: Andrew Donnellan <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Sasha Levin <[email protected]>
matttbe pushed a commit that referenced this issue Jan 25, 2023
[ Upstream commit b18cba09e374637a0a3759d856a6bca94c133952 ]

Commit 9130b8d ("SUNRPC: allow for upcalls for the same uid
but different gss service") introduced `auth` argument to
__gss_find_upcall(), but in gss_pipe_downcall() it was left as NULL
since it (and auth->service) was not (yet) determined.

When multiple upcalls with the same uid and different service are
ongoing, it could happen that __gss_find_upcall(), which returns the
first match found in the pipe->in_downcall list, could not find the
correct gss_msg corresponding to the downcall we are looking for.
Moreover, it might return a msg which is not sent to rpc.gssd yet.

We could see mount.nfs process hung in D state with multiple mount.nfs
are executed in parallel.  The call trace below is of CentOS 7.9
kernel-3.10.0-1160.24.1.el7.x86_64 but we observed the same hang w/
elrepo kernel-ml-6.0.7-1.el7.

PID: 71258  TASK: ffff91ebd4be0000  CPU: 36  COMMAND: "mount.nfs"
 #0 [ffff9203ca3234f8] __schedule at ffffffffa3b8899f
 #1 [ffff9203ca323580] schedule at ffffffffa3b88eb9
 #2 [ffff9203ca323590] gss_cred_init at ffffffffc0355818 [auth_rpcgss]
 #3 [ffff9203ca323658] rpcauth_lookup_credcache at ffffffffc0421ebc
[sunrpc]
 #4 [ffff9203ca3236d8] gss_lookup_cred at ffffffffc0353633 [auth_rpcgss]
 #5 [ffff9203ca3236e8] rpcauth_lookupcred at ffffffffc0421581 [sunrpc]
 #6 [ffff9203ca323740] rpcauth_refreshcred at ffffffffc04223d3 [sunrpc]
 #7 [ffff9203ca3237a0] call_refresh at ffffffffc04103dc [sunrpc]
 #8 [ffff9203ca3237b8] __rpc_execute at ffffffffc041e1c9 [sunrpc]
 #9 [ffff9203ca323820] rpc_execute at ffffffffc0420a48 [sunrpc]

The scenario is like this. Let's say there are two upcalls for
services A and B, A -> B in pipe->in_downcall, B -> A in pipe->pipe.

When rpc.gssd reads pipe to get the upcall msg corresponding to
service B from pipe->pipe and then writes the response, in
gss_pipe_downcall the msg corresponding to service A will be picked
because only uid is used to find the msg and it is before the one for
B in pipe->in_downcall.  And the process waiting for the msg
corresponding to service A will be woken up.

Actual scheduing of that process might be after rpc.gssd processes the
next msg.  In rpc_pipe_generic_upcall it clears msg->errno (for A).
The process is scheduled to see gss_msg->ctx == NULL and
gss_msg->msg.errno == 0, therefore it cannot break the loop in
gss_create_upcall and is never woken up after that.

This patch adds a simple check to ensure that a msg which is not
sent to rpc.gssd yet is not chosen as the matching upcall upon
receiving a downcall.

Signed-off-by: minoura makoto <[email protected]>
Signed-off-by: Hiroshi Shimamoto <[email protected]>
Tested-by: Hiroshi Shimamoto <[email protected]>
Cc: Trond Myklebust <[email protected]>
Fixes: 9130b8d ("SUNRPC: allow for upcalls for same uid but different gss service")
Signed-off-by: Trond Myklebust <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
matttbe pushed a commit that referenced this issue Jan 25, 2023
…g the sock

[ Upstream commit 3cf7203ca620682165706f70a1b12b5194607dce ]

There is a race condition in vxlan that when deleting a vxlan device
during receiving packets, there is a possibility that the sock is
released after getting vxlan_sock vs from sk_user_data. Then in
later vxlan_ecn_decapsulate(), vxlan_get_sk_family() we will got
NULL pointer dereference. e.g.

   #0 [ffffa25ec6978a38] machine_kexec at ffffffff8c669757
   #1 [ffffa25ec6978a90] __crash_kexec at ffffffff8c7c0a4d
   #2 [ffffa25ec6978b58] crash_kexec at ffffffff8c7c1c48
   #3 [ffffa25ec6978b60] oops_end at ffffffff8c627f2b
   #4 [ffffa25ec6978b80] page_fault_oops at ffffffff8c678fcb
   #5 [ffffa25ec6978bd8] exc_page_fault at ffffffff8d109542
   #6 [ffffa25ec6978c00] asm_exc_page_fault at ffffffff8d200b62
      [exception RIP: vxlan_ecn_decapsulate+0x3b]
      RIP: ffffffffc1014e7b  RSP: ffffa25ec6978cb0  RFLAGS: 00010246
      RAX: 0000000000000008  RBX: ffff8aa000888000  RCX: 0000000000000000
      RDX: 000000000000000e  RSI: ffff8a9fc7ab803e  RDI: ffff8a9fd1168700
      RBP: ffff8a9fc7ab803e   R8: 0000000000700000   R9: 00000000000010ae
      R10: ffff8a9fcb748980  R11: 0000000000000000  R12: ffff8a9fd1168700
      R13: ffff8aa000888000  R14: 00000000002a0000  R15: 00000000000010ae
      ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
   #7 [ffffa25ec6978ce8] vxlan_rcv at ffffffffc10189cd [vxlan]
   #8 [ffffa25ec6978d90] udp_queue_rcv_one_skb at ffffffff8cfb6507
   #9 [ffffa25ec6978dc0] udp_unicast_rcv_skb at ffffffff8cfb6e45
  #10 [ffffa25ec6978dc8] __udp4_lib_rcv at ffffffff8cfb8807
  #11 [ffffa25ec6978e20] ip_protocol_deliver_rcu at ffffffff8cf76951
  #12 [ffffa25ec6978e48] ip_local_deliver at ffffffff8cf76bde
  #13 [ffffa25ec6978ea0] __netif_receive_skb_one_core at ffffffff8cecde9b
  #14 [ffffa25ec6978ec8] process_backlog at ffffffff8cece139
  #15 [ffffa25ec6978f00] __napi_poll at ffffffff8ceced1a
  #16 [ffffa25ec6978f28] net_rx_action at ffffffff8cecf1f3
  #17 [ffffa25ec6978fa0] __softirqentry_text_start at ffffffff8d4000ca
  #18 [ffffa25ec6978ff0] do_softirq at ffffffff8c6fbdc3

Reproducer: https://github.com/Mellanox/ovs-tests/blob/master/test-ovs-vxlan-remove-tunnel-during-traffic.sh

Fix this by waiting for all sk_user_data reader to finish before
releasing the sock.

Reported-by: Jianlin Shi <[email protected]>
Suggested-by: Jakub Sitnicki <[email protected]>
Fixes: 6a93cc9 ("udp-tunnel: Add a few more UDP tunnel APIs")
Signed-off-by: Hangbin Liu <[email protected]>
Reviewed-by: Jiri Pirko <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
matttbe pushed a commit that referenced this issue Jan 25, 2023
[ Upstream commit 6c606e57eecc37d6b36d732b1ff7e55b7dc32dd4 ]

It's unsafe to use rtas_busy_delay() to handle a busy status from
the ibm,os-term RTAS function in rtas_os_term():

Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
BUG: sleeping function called from invalid context at arch/powerpc/kernel/rtas.c:618
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 1, name: swapper/0
preempt_count: 2, expected: 0
CPU: 7 PID: 1 Comm: swapper/0 Tainted: G      D            6.0.0-rc5-02182-gf8553a572277-dirty #9
Call Trace:
[c000000007b8f000] [c000000001337110] dump_stack_lvl+0xb4/0x110 (unreliable)
[c000000007b8f040] [c0000000002440e4] __might_resched+0x394/0x3c0
[c000000007b8f0e0] [c00000000004f680] rtas_busy_delay+0x120/0x1b0
[c000000007b8f100] [c000000000052d04] rtas_os_term+0xb8/0xf4
[c000000007b8f180] [c0000000001150fc] pseries_panic+0x50/0x68
[c000000007b8f1f0] [c000000000036354] ppc_panic_platform_handler+0x34/0x50
[c000000007b8f210] [c0000000002303c4] notifier_call_chain+0xd4/0x1c0
[c000000007b8f2b0] [c0000000002306cc] atomic_notifier_call_chain+0xac/0x1c0
[c000000007b8f2f0] [c0000000001d62b8] panic+0x228/0x4d0
[c000000007b8f390] [c0000000001e573c] do_exit+0x140c/0x1420
[c000000007b8f480] [c0000000001e586c] make_task_dead+0xdc/0x200

Use rtas_busy_delay_time() instead, which signals without side effects
whether to attempt the ibm,os-term RTAS call again.

Signed-off-by: Nathan Lynch <[email protected]>
Reviewed-by: Nicholas Piggin <[email protected]>
Reviewed-by: Andrew Donnellan <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Sasha Levin <[email protected]>
matttbe pushed a commit that referenced this issue Jan 25, 2023
[ Upstream commit b18cba09e374637a0a3759d856a6bca94c133952 ]

Commit 9130b8d ("SUNRPC: allow for upcalls for the same uid
but different gss service") introduced `auth` argument to
__gss_find_upcall(), but in gss_pipe_downcall() it was left as NULL
since it (and auth->service) was not (yet) determined.

When multiple upcalls with the same uid and different service are
ongoing, it could happen that __gss_find_upcall(), which returns the
first match found in the pipe->in_downcall list, could not find the
correct gss_msg corresponding to the downcall we are looking for.
Moreover, it might return a msg which is not sent to rpc.gssd yet.

We could see mount.nfs process hung in D state with multiple mount.nfs
are executed in parallel.  The call trace below is of CentOS 7.9
kernel-3.10.0-1160.24.1.el7.x86_64 but we observed the same hang w/
elrepo kernel-ml-6.0.7-1.el7.

PID: 71258  TASK: ffff91ebd4be0000  CPU: 36  COMMAND: "mount.nfs"
 #0 [ffff9203ca3234f8] __schedule at ffffffffa3b8899f
 #1 [ffff9203ca323580] schedule at ffffffffa3b88eb9
 #2 [ffff9203ca323590] gss_cred_init at ffffffffc0355818 [auth_rpcgss]
 #3 [ffff9203ca323658] rpcauth_lookup_credcache at ffffffffc0421ebc
[sunrpc]
 #4 [ffff9203ca3236d8] gss_lookup_cred at ffffffffc0353633 [auth_rpcgss]
 #5 [ffff9203ca3236e8] rpcauth_lookupcred at ffffffffc0421581 [sunrpc]
 #6 [ffff9203ca323740] rpcauth_refreshcred at ffffffffc04223d3 [sunrpc]
 #7 [ffff9203ca3237a0] call_refresh at ffffffffc04103dc [sunrpc]
 #8 [ffff9203ca3237b8] __rpc_execute at ffffffffc041e1c9 [sunrpc]
 #9 [ffff9203ca323820] rpc_execute at ffffffffc0420a48 [sunrpc]

The scenario is like this. Let's say there are two upcalls for
services A and B, A -> B in pipe->in_downcall, B -> A in pipe->pipe.

When rpc.gssd reads pipe to get the upcall msg corresponding to
service B from pipe->pipe and then writes the response, in
gss_pipe_downcall the msg corresponding to service A will be picked
because only uid is used to find the msg and it is before the one for
B in pipe->in_downcall.  And the process waiting for the msg
corresponding to service A will be woken up.

Actual scheduing of that process might be after rpc.gssd processes the
next msg.  In rpc_pipe_generic_upcall it clears msg->errno (for A).
The process is scheduled to see gss_msg->ctx == NULL and
gss_msg->msg.errno == 0, therefore it cannot break the loop in
gss_create_upcall and is never woken up after that.

This patch adds a simple check to ensure that a msg which is not
sent to rpc.gssd yet is not chosen as the matching upcall upon
receiving a downcall.

Signed-off-by: minoura makoto <[email protected]>
Signed-off-by: Hiroshi Shimamoto <[email protected]>
Tested-by: Hiroshi Shimamoto <[email protected]>
Cc: Trond Myklebust <[email protected]>
Fixes: 9130b8d ("SUNRPC: allow for upcalls for same uid but different gss service")
Signed-off-by: Trond Myklebust <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
matttbe pushed a commit that referenced this issue Apr 7, 2023
commit 60eed1e3d45045623e46944ebc7c42c30a4350f0 upstream.

code path:

ocfs2_ioctl_move_extents
 ocfs2_move_extents
  ocfs2_defrag_extent
   __ocfs2_move_extent
    + ocfs2_journal_access_di
    + ocfs2_split_extent  //sub-paths call jbd2_journal_restart
    + ocfs2_journal_dirty //crash by jbs2 ASSERT

crash stacks:

PID: 11297  TASK: ffff974a676dcd00  CPU: 67  COMMAND: "defragfs.ocfs2"
 #0 [ffffb25d8dad3900] machine_kexec at ffffffff8386fe01
 #1 [ffffb25d8dad3958] __crash_kexec at ffffffff8395959d
 #2 [ffffb25d8dad3a20] crash_kexec at ffffffff8395a45d
 #3 [ffffb25d8dad3a38] oops_end at ffffffff83836d3f
 #4 [ffffb25d8dad3a58] do_trap at ffffffff83833205
 #5 [ffffb25d8dad3aa0] do_invalid_op at ffffffff83833aa6
 #6 [ffffb25d8dad3ac0] invalid_op at ffffffff84200d18
    [exception RIP: jbd2_journal_dirty_metadata+0x2ba]
    RIP: ffffffffc09ca54a  RSP: ffffb25d8dad3b70  RFLAGS: 00010207
    RAX: 0000000000000000  RBX: ffff9706eedc5248  RCX: 0000000000000000
    RDX: 0000000000000001  RSI: ffff97337029ea28  RDI: ffff9706eedc5250
    RBP: ffff9703c3520200   R8: 000000000f46b0b2   R9: 0000000000000000
    R10: 0000000000000001  R11: 00000001000000fe  R12: ffff97337029ea28
    R13: 0000000000000000  R14: ffff9703de59bf60  R15: ffff9706eedc5250
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #7 [ffffb25d8dad3ba8] ocfs2_journal_dirty at ffffffffc137fb95 [ocfs2]
 #8 [ffffb25d8dad3be8] __ocfs2_move_extent at ffffffffc139a950 [ocfs2]
 #9 [ffffb25d8dad3c80] ocfs2_defrag_extent at ffffffffc139b2d2 [ocfs2]

Analysis

This bug has the same root cause of 'commit 7f27ec9 ("ocfs2: call
ocfs2_journal_access_di() before ocfs2_journal_dirty() in
ocfs2_write_end_nolock()")'.  For this bug, jbd2_journal_restart() is
called by ocfs2_split_extent() during defragmenting.

How to fix

For ocfs2_split_extent() can handle journal operations totally by itself.
Caller doesn't need to call journal access/dirty pair, and caller only
needs to call journal start/stop pair.  The fix method is to remove
journal access/dirty from __ocfs2_move_extent().

The discussion for this patch:
https://oss.oracle.com/pipermail/ocfs2-devel/2023-February/000647.html

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Heming Zhao <[email protected]>
Reviewed-by: Joseph Qi <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Joel Becker <[email protected]>
Cc: Junxiao Bi <[email protected]>
Cc: Changwei Ge <[email protected]>
Cc: Gang He <[email protected]>
Cc: Jun Piao <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
matttbe pushed a commit that referenced this issue Apr 7, 2023
commit 60eed1e3d45045623e46944ebc7c42c30a4350f0 upstream.

code path:

ocfs2_ioctl_move_extents
 ocfs2_move_extents
  ocfs2_defrag_extent
   __ocfs2_move_extent
    + ocfs2_journal_access_di
    + ocfs2_split_extent  //sub-paths call jbd2_journal_restart
    + ocfs2_journal_dirty //crash by jbs2 ASSERT

crash stacks:

PID: 11297  TASK: ffff974a676dcd00  CPU: 67  COMMAND: "defragfs.ocfs2"
 #0 [ffffb25d8dad3900] machine_kexec at ffffffff8386fe01
 #1 [ffffb25d8dad3958] __crash_kexec at ffffffff8395959d
 #2 [ffffb25d8dad3a20] crash_kexec at ffffffff8395a45d
 #3 [ffffb25d8dad3a38] oops_end at ffffffff83836d3f
 #4 [ffffb25d8dad3a58] do_trap at ffffffff83833205
 #5 [ffffb25d8dad3aa0] do_invalid_op at ffffffff83833aa6
 #6 [ffffb25d8dad3ac0] invalid_op at ffffffff84200d18
    [exception RIP: jbd2_journal_dirty_metadata+0x2ba]
    RIP: ffffffffc09ca54a  RSP: ffffb25d8dad3b70  RFLAGS: 00010207
    RAX: 0000000000000000  RBX: ffff9706eedc5248  RCX: 0000000000000000
    RDX: 0000000000000001  RSI: ffff97337029ea28  RDI: ffff9706eedc5250
    RBP: ffff9703c3520200   R8: 000000000f46b0b2   R9: 0000000000000000
    R10: 0000000000000001  R11: 00000001000000fe  R12: ffff97337029ea28
    R13: 0000000000000000  R14: ffff9703de59bf60  R15: ffff9706eedc5250
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #7 [ffffb25d8dad3ba8] ocfs2_journal_dirty at ffffffffc137fb95 [ocfs2]
 #8 [ffffb25d8dad3be8] __ocfs2_move_extent at ffffffffc139a950 [ocfs2]
 #9 [ffffb25d8dad3c80] ocfs2_defrag_extent at ffffffffc139b2d2 [ocfs2]

Analysis

This bug has the same root cause of 'commit 7f27ec9 ("ocfs2: call
ocfs2_journal_access_di() before ocfs2_journal_dirty() in
ocfs2_write_end_nolock()")'.  For this bug, jbd2_journal_restart() is
called by ocfs2_split_extent() during defragmenting.

How to fix

For ocfs2_split_extent() can handle journal operations totally by itself.
Caller doesn't need to call journal access/dirty pair, and caller only
needs to call journal start/stop pair.  The fix method is to remove
journal access/dirty from __ocfs2_move_extent().

The discussion for this patch:
https://oss.oracle.com/pipermail/ocfs2-devel/2023-February/000647.html

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Heming Zhao <[email protected]>
Reviewed-by: Joseph Qi <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Joel Becker <[email protected]>
Cc: Junxiao Bi <[email protected]>
Cc: Changwei Ge <[email protected]>
Cc: Gang He <[email protected]>
Cc: Jun Piao <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
matttbe pushed a commit that referenced this issue Apr 7, 2023
commit 60eed1e3d45045623e46944ebc7c42c30a4350f0 upstream.

code path:

ocfs2_ioctl_move_extents
 ocfs2_move_extents
  ocfs2_defrag_extent
   __ocfs2_move_extent
    + ocfs2_journal_access_di
    + ocfs2_split_extent  //sub-paths call jbd2_journal_restart
    + ocfs2_journal_dirty //crash by jbs2 ASSERT

crash stacks:

PID: 11297  TASK: ffff974a676dcd00  CPU: 67  COMMAND: "defragfs.ocfs2"
 #0 [ffffb25d8dad3900] machine_kexec at ffffffff8386fe01
 #1 [ffffb25d8dad3958] __crash_kexec at ffffffff8395959d
 #2 [ffffb25d8dad3a20] crash_kexec at ffffffff8395a45d
 #3 [ffffb25d8dad3a38] oops_end at ffffffff83836d3f
 #4 [ffffb25d8dad3a58] do_trap at ffffffff83833205
 #5 [ffffb25d8dad3aa0] do_invalid_op at ffffffff83833aa6
 #6 [ffffb25d8dad3ac0] invalid_op at ffffffff84200d18
    [exception RIP: jbd2_journal_dirty_metadata+0x2ba]
    RIP: ffffffffc09ca54a  RSP: ffffb25d8dad3b70  RFLAGS: 00010207
    RAX: 0000000000000000  RBX: ffff9706eedc5248  RCX: 0000000000000000
    RDX: 0000000000000001  RSI: ffff97337029ea28  RDI: ffff9706eedc5250
    RBP: ffff9703c3520200   R8: 000000000f46b0b2   R9: 0000000000000000
    R10: 0000000000000001  R11: 00000001000000fe  R12: ffff97337029ea28
    R13: 0000000000000000  R14: ffff9703de59bf60  R15: ffff9706eedc5250
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #7 [ffffb25d8dad3ba8] ocfs2_journal_dirty at ffffffffc137fb95 [ocfs2]
 #8 [ffffb25d8dad3be8] __ocfs2_move_extent at ffffffffc139a950 [ocfs2]
 #9 [ffffb25d8dad3c80] ocfs2_defrag_extent at ffffffffc139b2d2 [ocfs2]

Analysis

This bug has the same root cause of 'commit 7f27ec9 ("ocfs2: call
ocfs2_journal_access_di() before ocfs2_journal_dirty() in
ocfs2_write_end_nolock()")'.  For this bug, jbd2_journal_restart() is
called by ocfs2_split_extent() during defragmenting.

How to fix

For ocfs2_split_extent() can handle journal operations totally by itself.
Caller doesn't need to call journal access/dirty pair, and caller only
needs to call journal start/stop pair.  The fix method is to remove
journal access/dirty from __ocfs2_move_extent().

The discussion for this patch:
https://oss.oracle.com/pipermail/ocfs2-devel/2023-February/000647.html

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Heming Zhao <[email protected]>
Reviewed-by: Joseph Qi <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Joel Becker <[email protected]>
Cc: Junxiao Bi <[email protected]>
Cc: Changwei Ge <[email protected]>
Cc: Gang He <[email protected]>
Cc: Jun Piao <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
dreibh pushed a commit to dreibh/mptcp that referenced this issue Aug 8, 2023
[ Upstream commit 05bb0167c80b8f93c6a4e0451b7da9b96db990c2 ]

ACPICA commit 770653e3ba67c30a629ca7d12e352d83c2541b1e

Before this change we see the following UBSAN stack trace in Fuchsia:

  #0    0x000021e4213b3302 in acpi_ds_init_aml_walk(struct acpi_walk_state*, union acpi_parse_object*, struct acpi_namespace_node*, u8*, u32, struct acpi_evaluate_info*, u8) ../../third_party/acpica/source/components/dispatcher/dswstate.c:682 <platform-bus-x86.so>+0x233302
  #1.2  0x000020d0f660777f in ubsan_get_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:41 <libclang_rt.asan.so>+0x3d77f
  #1.1  0x000020d0f660777f in maybe_print_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:51 <libclang_rt.asan.so>+0x3d77f
  #1    0x000020d0f660777f in ~scoped_report() compiler-rt/lib/ubsan/ubsan_diag.cpp:387 <libclang_rt.asan.so>+0x3d77f
  multipath-tcp#2    0x000020d0f660b96d in handlepointer_overflow_impl() compiler-rt/lib/ubsan/ubsan_handlers.cpp:809 <libclang_rt.asan.so>+0x4196d
  multipath-tcp#3    0x000020d0f660b50d in compiler-rt/lib/ubsan/ubsan_handlers.cpp:815 <libclang_rt.asan.so>+0x4150d
  multipath-tcp#4    0x000021e4213b3302 in acpi_ds_init_aml_walk(struct acpi_walk_state*, union acpi_parse_object*, struct acpi_namespace_node*, u8*, u32, struct acpi_evaluate_info*, u8) ../../third_party/acpica/source/components/dispatcher/dswstate.c:682 <platform-bus-x86.so>+0x233302
  multipath-tcp#5    0x000021e4213e2369 in acpi_ds_call_control_method(struct acpi_thread_state*, struct acpi_walk_state*, union acpi_parse_object*) ../../third_party/acpica/source/components/dispatcher/dsmethod.c:605 <platform-bus-x86.so>+0x262369
  multipath-tcp#6    0x000021e421437fac in acpi_ps_parse_aml(struct acpi_walk_state*) ../../third_party/acpica/source/components/parser/psparse.c:550 <platform-bus-x86.so>+0x2b7fac
  multipath-tcp#7    0x000021e4214464d2 in acpi_ps_execute_method(struct acpi_evaluate_info*) ../../third_party/acpica/source/components/parser/psxface.c:244 <platform-bus-x86.so>+0x2c64d2
  multipath-tcp#8    0x000021e4213aa052 in acpi_ns_evaluate(struct acpi_evaluate_info*) ../../third_party/acpica/source/components/namespace/nseval.c:250 <platform-bus-x86.so>+0x22a052
  multipath-tcp#9    0x000021e421413dd8 in acpi_ns_init_one_device(acpi_handle, u32, void*, void**) ../../third_party/acpica/source/components/namespace/nsinit.c:735 <platform-bus-x86.so>+0x293dd8
  multipath-tcp#10   0x000021e421429e98 in acpi_ns_walk_namespace(acpi_object_type, acpi_handle, u32, u32, acpi_walk_callback, acpi_walk_callback, void*, void**) ../../third_party/acpica/source/components/namespace/nswalk.c:298 <platform-bus-x86.so>+0x2a9e98
  multipath-tcp#11   0x000021e4214131ac in acpi_ns_initialize_devices(u32) ../../third_party/acpica/source/components/namespace/nsinit.c:268 <platform-bus-x86.so>+0x2931ac
  multipath-tcp#12   0x000021e42147c40d in acpi_initialize_objects(u32) ../../third_party/acpica/source/components/utilities/utxfinit.c:304 <platform-bus-x86.so>+0x2fc40d
  multipath-tcp#13   0x000021e42126d603 in acpi::acpi_impl::initialize_acpi(acpi::acpi_impl*) ../../src/devices/board/lib/acpi/acpi-impl.cc:224 <platform-bus-x86.so>+0xed603

Add a simple check that avoids incrementing a pointer by zero, but
otherwise behaves as before. Note that our findings are against ACPICA
20221020, but the same code exists on master.

Link: acpica/acpica@770653e3
Signed-off-by: Bob Moore <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
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