X aries cm 11.0 #1

DerRomtester · 2014-01-14T14:02:50Z

No description provided.

This reverts commit e25f257.

X aries cm 11.0

The filesystem layer expects pages in the block device's mapping to not be in highmem (the mapping's gfp mask is set in bdget()), but CMA can currently replace lowmem pages with highmem pages, leading to crashes in filesystem code such as the one below: Unable to handle kernel NULL pointer dereference at virtual address 00000400 pgd = c0c98000 [00000400] *pgd=00c91831, *pte=00000000, *ppte=00000000 Internal error: Oops: 817 [#1] PREEMPT SMP ARM CPU: 0 Not tainted (3.5.0-rc5+ #80) PC is at __memzero+0x24/0x80 ... Process fsstress (pid: 323, stack limit = 0xc0cbc2f0) Backtrace: [<c010e3f0>] (ext4_getblk+0x0/0x180) from [<c010e58c>] (ext4_bread+0x1c/0x98) [<c010e570>] (ext4_bread+0x0/0x98) from [<c0117944>] (ext4_mkdir+0x160/0x3bc) r4:c15337f0 [<c01177e4>] (ext4_mkdir+0x0/0x3bc) from [<c00c29e0>] (vfs_mkdir+0x8c/0x98) [<c00c2954>] (vfs_mkdir+0x0/0x98) from [<c00c2a60>] (sys_mkdirat+0x74/0xac) r6:00000000 r5:c152eb40 r4:000001ff r3:c14b43f0 [<c00c29ec>] (sys_mkdirat+0x0/0xac) from [<c00c2ab8>] (sys_mkdir+0x20/0x24) r6:beccdcf0 r5:00074000 r4:beccdbbc [<c00c2a98>] (sys_mkdir+0x0/0x24) from [<c000e3c0>] (ret_fast_syscall+0x0/0x30) Fix this by replacing only highmem pages with highmem. Change-Id: I6af2d509af48b5a586037be14bd3593b3f269d95 Reported-by: Laura Abbott <[email protected]> Signed-off-by: Rabin Vincent <[email protected]> Acked-by: Michal Nazarewicz <[email protected]> Signed-off-by: Marek Szyprowski <[email protected]> Signed-off-by: Laura Abbott <[email protected]>

The filesystem layer expects pages in the block device's mapping to not be in highmem (the mapping's gfp mask is set in bdget()), but CMA can currently replace lowmem pages with highmem pages, leading to crashes in filesystem code such as the one below: Unable to handle kernel NULL pointer dereference at virtual address 00000400 pgd = c0c98000 [00000400] *pgd=00c91831, *pte=00000000, *ppte=00000000 Internal error: Oops: 817 [didhiy#1] PREEMPT SMP ARM CPU: 0 Not tainted (3.5.0-rc5+ #80) PC is at __memzero+0x24/0x80 ... Process fsstress (pid: 323, stack limit = 0xc0cbc2f0) Backtrace: [<c010e3f0>] (ext4_getblk+0x0/0x180) from [<c010e58c>] (ext4_bread+0x1c/0x98) [<c010e570>] (ext4_bread+0x0/0x98) from [<c0117944>] (ext4_mkdir+0x160/0x3bc) r4:c15337f0 [<c01177e4>] (ext4_mkdir+0x0/0x3bc) from [<c00c29e0>] (vfs_mkdir+0x8c/0x98) [<c00c2954>] (vfs_mkdir+0x0/0x98) from [<c00c2a60>] (sys_mkdirat+0x74/0xac) r6:00000000 r5:c152eb40 r4:000001ff r3:c14b43f0 [<c00c29ec>] (sys_mkdirat+0x0/0xac) from [<c00c2ab8>] (sys_mkdir+0x20/0x24) r6:beccdcf0 r5:00074000 r4:beccdbbc [<c00c2a98>] (sys_mkdir+0x0/0x24) from [<c000e3c0>] (ret_fast_syscall+0x0/0x30) Fix this by replacing only highmem pages with highmem. Change-Id: I6af2d509af48b5a586037be14bd3593b3f269d95 Reported-by: Laura Abbott <[email protected]> Signed-off-by: Rabin Vincent <[email protected]> Acked-by: Michal Nazarewicz <[email protected]> Signed-off-by: Marek Szyprowski <[email protected]> Signed-off-by: Laura Abbott <[email protected]>

…ssion() While running stress tests on adding and deleting ftrace instances I hit this bug: BUG: unable to handle kernel NULL pointer dereference at 0000000000000020 IP: selinux_inode_permission+0x85/0x160 PGD 63681067 PUD 7ddbe067 PMD 0 Oops: 0000 [#1] PREEMPT CPU: 0 PID: 5634 Comm: ftrace-test-mki Not tainted 3.13.0-rc4-test-00033-gd2a6dde-dirty #20 Hardware name: /DG965MQ, BIOS MQ96510J.86A.0372.2006.0605.1717 06/05/2006 task: ffff880078375800 ti: ffff88007ddb0000 task.ti: ffff88007ddb0000 RIP: 0010:[<ffffffff812d8bc5>] [<ffffffff812d8bc5>] selinux_inode_permission+0x85/0x160 RSP: 0018:ffff88007ddb1c48 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000800000 RCX: ffff88006dd43840 RDX: 0000000000000001 RSI: 0000000000000081 RDI: ffff88006ee46000 RBP: ffff88007ddb1c88 R08: 0000000000000000 R09: ffff88007ddb1c54 R10: 6e6576652f6f6f66 R11: 0000000000000003 R12: 0000000000000000 R13: 0000000000000081 R14: ffff88006ee46000 R15: 0000000000000000 FS: 00007f217b5b6700(0000) GS:ffffffff81e21000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033^M CR2: 0000000000000020 CR3: 000000006a0fe000 CR4: 00000000000007f0 Call Trace: security_inode_permission+0x1c/0x30 __inode_permission+0x41/0xa0 inode_permission+0x18/0x50 link_path_walk+0x66/0x920 path_openat+0xa6/0x6c0 do_filp_open+0x43/0xa0 do_sys_open+0x146/0x240 SyS_open+0x1e/0x20 system_call_fastpath+0x16/0x1b Code: 84 a1 00 00 00 81 e3 00 20 00 00 89 d8 83 c8 02 40 f6 c6 04 0f 45 d8 40 f6 c6 08 74 71 80 cf 02 49 8b 46 38 4c 8d 4d cc 45 31 c0 <0f> b7 50 20 8b 70 1c 48 8b 41 70 89 d9 8b 78 04 e8 36 cf ff ff RIP selinux_inode_permission+0x85/0x160 CR2: 0000000000000020 Investigating, I found that the inode->i_security was NULL, and the dereference of it caused the oops. in selinux_inode_permission(): isec = inode->i_security; rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd); Note, the crash came from stressing the deletion and reading of debugfs files. I was not able to recreate this via normal files. But I'm not sure they are safe. It may just be that the race window is much harder to hit. What seems to have happened (and what I have traced), is the file is being opened at the same time the file or directory is being deleted. As the dentry and inode locks are not held during the path walk, nor is the inodes ref counts being incremented, there is nothing saving these structures from being discarded except for an rcu_read_lock(). The rcu_read_lock() protects against freeing of the inode, but it does not protect freeing of the inode_security_struct. Now if the freeing of the i_security happens with a call_rcu(), and the i_security field of the inode is not changed (it gets freed as the inode gets freed) then there will be no issue here. (Linus Torvalds suggested not setting the field to NULL such that we do not need to check if it is NULL in the permission check). Note, this is a hack, but it fixes the problem at hand. A real fix is to restructure the destroy_inode() to call all the destructor handlers from the RCU callback. But that is a major job to do, and requires a lot of work. For now, we just band-aid this bug with this fix (it works), and work on a more maintainable solution in the future. Link: http://lkml.kernel.org/r/[email protected] Link: http://lkml.kernel.org/r/[email protected] Cc: [email protected] Signed-off-by: Steven Rostedt <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>

Setting an empty security context (length=0) on a file will lead to incorrectly dereferencing the type and other fields of the security context structure, yielding a kernel BUG. As a zero-length security context is never valid, just reject all such security contexts whether coming from userspace via setxattr or coming from the filesystem upon a getxattr request by SELinux. Setting a security context value (empty or otherwise) unknown to SELinux in the first place is only possible for a root process (CAP_MAC_ADMIN), and, if running SELinux in enforcing mode, only if the corresponding SELinux mac_admin permission is also granted to the domain by policy. In Fedora policies, this is only allowed for specific domains such as livecd for setting down security contexts that are not defined in the build host policy. [On Android, this can only be set by root/CAP_MAC_ADMIN processes, and if running SELinux in enforcing mode, only if mac_admin permission is granted in policy. In Android 4.4, this would only be allowed for root/CAP_MAC_ADMIN processes that are also in unconfined domains. In current AOSP master, mac_admin is not allowed for any domains except the recovery console which has a legitimate need for it. The other potential vector is mounting a maliciously crafted filesystem for which SELinux fetches xattrs (e.g. an ext4 filesystem on a SDcard). However, the end result is only a local denial-of-service (DOS) due to kernel BUG. This fix is queued for 3.14.] Reproducer: su setenforce 0 touch foo setfattr -n security.selinux foo Caveat: Relabeling or removing foo after doing the above may not be possible without booting with SELinux disabled. Any subsequent access to foo after doing the above will also trigger the BUG. BUG output from Matthew Thode: [ 473.893141] ------------[ cut here ]------------ [ 473.962110] kernel BUG at security/selinux/ss/services.c:654! [ 473.995314] invalid opcode: 0000 [coolya#6] SMP [ 474.027196] Modules linked in: [ 474.058118] CPU: 0 PID: 8138 Comm: ls Tainted: G D I 3.13.0-grsec #1 [ 474.116637] Hardware name: Supermicro X8ST3/X8ST3, BIOS 2.0 07/29/10 [ 474.149768] task: ffff8805f50cd010 ti: ffff8805f50cd488 task.ti: ffff8805f50cd488 [ 474.183707] RIP: 0010:[<ffffffff814681c7>] [<ffffffff814681c7>] context_struct_compute_av+0xce/0x308 [ 474.219954] RSP: 0018:ffff8805c0ac3c38 EFLAGS: 00010246 [ 474.252253] RAX: 0000000000000000 RBX: ffff8805c0ac3d94 RCX: 0000000000000100 [ 474.287018] RDX: ffff8805e8aac000 RSI: 00000000ffffffff RDI: ffff8805e8aaa000 [ 474.321199] RBP: ffff8805c0ac3cb8 R08: 0000000000000010 R09: 0000000000000006 [ 474.357446] R10: 0000000000000000 R11: ffff8805c567a000 R12: 0000000000000006 [ 474.419191] R13: ffff8805c2b74e88 R14: 00000000000001da R15: 0000000000000000 [ 474.453816] FS: 00007f2e75220800(0000) GS:ffff88061fc00000(0000) knlGS:0000000000000000 [ 474.489254] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 474.522215] CR2: 00007f2e74716090 CR3: 00000005c085e000 CR4: 00000000000207f0 [ 474.556058] Stack: [ 474.584325] ffff8805c0ac3c98 ffffffff811b549b ffff8805c0ac3c98 ffff8805f1190a40 [ 474.618913] ffff8805a6202f08 ffff8805c2b74e88 00068800d0464990 ffff8805e8aac860 [ 474.653955] ffff8805c0ac3cb8 000700068113833a ffff880606c75060 ffff8805c0ac3d94 [ 474.690461] Call Trace: [ 474.723779] [<ffffffff811b549b>] ? lookup_fast+0x1cd/0x22a [ 474.778049] [<ffffffff81468824>] security_compute_av+0xf4/0x20b [ 474.811398] [<ffffffff8196f419>] avc_compute_av+0x2a/0x179 [ 474.843813] [<ffffffff8145727b>] avc_has_perm+0x45/0xf4 [ 474.875694] [<ffffffff81457d0e>] inode_has_perm+0x2a/0x31 [ 474.907370] [<ffffffff81457e76>] selinux_inode_getattr+0x3c/0x3e [ 474.938726] [<ffffffff81455cf6>] security_inode_getattr+0x1b/0x22 [ 474.970036] [<ffffffff811b057d>] vfs_getattr+0x19/0x2d [ 475.000618] [<ffffffff811b05e5>] vfs_fstatat+0x54/0x91 [ 475.030402] [<ffffffff811b063b>] vfs_lstat+0x19/0x1b [ 475.061097] [<ffffffff811b077e>] SyS_newlstat+0x15/0x30 [ 475.094595] [<ffffffff8113c5c1>] ? __audit_syscall_entry+0xa1/0xc3 [ 475.148405] [<ffffffff8197791e>] system_call_fastpath+0x16/0x1b [ 475.179201] Code: 00 48 85 c0 48 89 45 b8 75 02 0f 0b 48 8b 45 a0 48 8b 3d 45 d0 b6 00 8b 40 08 89 c6 ff ce e8 d1 b0 06 00 48 85 c0 49 89 c7 75 02 <0f> 0b 48 8b 45 b8 4c 8b 28 eb 1e 49 8d 7d 08 be 80 01 00 00 e8 [ 475.255884] RIP [<ffffffff814681c7>] context_struct_compute_av+0xce/0x308 [ 475.296120] RSP <ffff8805c0ac3c38> [ 475.328734] ---[ end trace f076482e9d754adc ]--- [sds: commit message edited to note Android implications and to generate a unique Change-Id for gerrit] Change-Id: I4d5389f0cfa72b5f59dada45081fa47e03805413 Reported-by: Matthew Thode <[email protected]> Signed-off-by: Stephen Smalley <[email protected]> Cc: [email protected] Signed-off-by: Paul Moore <[email protected]>

Setting an empty security context (length=0) on a file will lead to incorrectly dereferencing the type and other fields of the security context structure, yielding a kernel BUG. As a zero-length security context is never valid, just reject all such security contexts whether coming from userspace via setxattr or coming from the filesystem upon a getxattr request by SELinux. Setting a security context value (empty or otherwise) unknown to SELinux in the first place is only possible for a root process (CAP_MAC_ADMIN), and, if running SELinux in enforcing mode, only if the corresponding SELinux mac_admin permission is also granted to the domain by policy. In Fedora policies, this is only allowed for specific domains such as livecd for setting down security contexts that are not defined in the build host policy. [On Android, this can only be set by root/CAP_MAC_ADMIN processes, and if running SELinux in enforcing mode, only if mac_admin permission is granted in policy. In Android 4.4, this would only be allowed for root/CAP_MAC_ADMIN processes that are also in unconfined domains. In current AOSP master, mac_admin is not allowed for any domains except the recovery console which has a legitimate need for it. The other potential vector is mounting a maliciously crafted filesystem for which SELinux fetches xattrs (e.g. an ext4 filesystem on a SDcard). However, the end result is only a local denial-of-service (DOS) due to kernel BUG. This fix is queued for 3.14.] Reproducer: su setenforce 0 touch foo setfattr -n security.selinux foo Caveat: Relabeling or removing foo after doing the above may not be possible without booting with SELinux disabled. Any subsequent access to foo after doing the above will also trigger the BUG. BUG output from Matthew Thode: [ 473.893141] ------------[ cut here ]------------ [ 473.962110] kernel BUG at security/selinux/ss/services.c:654! [ 473.995314] invalid opcode: 0000 [coolya#6] SMP [ 474.027196] Modules linked in: [ 474.058118] CPU: 0 PID: 8138 Comm: ls Tainted: G D I 3.13.0-grsec didhiy#1 [ 474.116637] Hardware name: Supermicro X8ST3/X8ST3, BIOS 2.0 07/29/10 [ 474.149768] task: ffff8805f50cd010 ti: ffff8805f50cd488 task.ti: ffff8805f50cd488 [ 474.183707] RIP: 0010:[<ffffffff814681c7>] [<ffffffff814681c7>] context_struct_compute_av+0xce/0x308 [ 474.219954] RSP: 0018:ffff8805c0ac3c38 EFLAGS: 00010246 [ 474.252253] RAX: 0000000000000000 RBX: ffff8805c0ac3d94 RCX: 0000000000000100 [ 474.287018] RDX: ffff8805e8aac000 RSI: 00000000ffffffff RDI: ffff8805e8aaa000 [ 474.321199] RBP: ffff8805c0ac3cb8 R08: 0000000000000010 R09: 0000000000000006 [ 474.357446] R10: 0000000000000000 R11: ffff8805c567a000 R12: 0000000000000006 [ 474.419191] R13: ffff8805c2b74e88 R14: 00000000000001da R15: 0000000000000000 [ 474.453816] FS: 00007f2e75220800(0000) GS:ffff88061fc00000(0000) knlGS:0000000000000000 [ 474.489254] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 474.522215] CR2: 00007f2e74716090 CR3: 00000005c085e000 CR4: 00000000000207f0 [ 474.556058] Stack: [ 474.584325] ffff8805c0ac3c98 ffffffff811b549b ffff8805c0ac3c98 ffff8805f1190a40 [ 474.618913] ffff8805a6202f08 ffff8805c2b74e88 00068800d0464990 ffff8805e8aac860 [ 474.653955] ffff8805c0ac3cb8 000700068113833a ffff880606c75060 ffff8805c0ac3d94 [ 474.690461] Call Trace: [ 474.723779] [<ffffffff811b549b>] ? lookup_fast+0x1cd/0x22a [ 474.778049] [<ffffffff81468824>] security_compute_av+0xf4/0x20b [ 474.811398] [<ffffffff8196f419>] avc_compute_av+0x2a/0x179 [ 474.843813] [<ffffffff8145727b>] avc_has_perm+0x45/0xf4 [ 474.875694] [<ffffffff81457d0e>] inode_has_perm+0x2a/0x31 [ 474.907370] [<ffffffff81457e76>] selinux_inode_getattr+0x3c/0x3e [ 474.938726] [<ffffffff81455cf6>] security_inode_getattr+0x1b/0x22 [ 474.970036] [<ffffffff811b057d>] vfs_getattr+0x19/0x2d [ 475.000618] [<ffffffff811b05e5>] vfs_fstatat+0x54/0x91 [ 475.030402] [<ffffffff811b063b>] vfs_lstat+0x19/0x1b [ 475.061097] [<ffffffff811b077e>] SyS_newlstat+0x15/0x30 [ 475.094595] [<ffffffff8113c5c1>] ? __audit_syscall_entry+0xa1/0xc3 [ 475.148405] [<ffffffff8197791e>] system_call_fastpath+0x16/0x1b [ 475.179201] Code: 00 48 85 c0 48 89 45 b8 75 02 0f 0b 48 8b 45 a0 48 8b 3d 45 d0 b6 00 8b 40 08 89 c6 ff ce e8 d1 b0 06 00 48 85 c0 49 89 c7 75 02 <0f> 0b 48 8b 45 b8 4c 8b 28 eb 1e 49 8d 7d 08 be 80 01 00 00 e8 [ 475.255884] RIP [<ffffffff814681c7>] context_struct_compute_av+0xce/0x308 [ 475.296120] RSP <ffff8805c0ac3c38> [ 475.328734] ---[ end trace f076482e9d754adc ]--- [sds: commit message edited to note Android implications and to generate a unique Change-Id for gerrit] Change-Id: I4d5389f0cfa72b5f59dada45081fa47e03805413 Reported-by: Matthew Thode <[email protected]> Signed-off-by: Stephen Smalley <[email protected]> Cc: [email protected] Signed-off-by: Paul Moore <[email protected]>

ext4: prevent kernel panic in case of uninitialized jinode In some cases the kernel crash occurs during system suspend/resume: [ 4095.041351] Unable to handle kernel NULL pointer dereference at virtual address 00000000 [ 4095.050689] pgd = c0004000 [ 4095.053985] [00000000] *pgd=00000000 [ 4095.058807] Internal error: Oops: 5 [didhiy#1] PREEMPT SMP [ 4095.064483] Modules linked in: wl12xx mac80211 pvrsrvkm_sgx540_120 cfg80211 compat [last unloaded: wl12xx_sdio] [ 4095.064575] CPU: 1 Tainted: G B (3.0.31-01807-gfac16a0 didhiy#1) [ 4095.064605] PC is at jbd2_journal_file_inode+0x38/0x118 [ 4095.064666] LR is at mpage_da_map_and_submit+0x48c/0x618 [ 4095.064697] pc : [<c01da5a8>] lr : [<c01aeac0>] psr: 60000013 [ 4095.064697] sp : c6e07c80 ip : c6e07ca0 fp : c6e07c9c [ 4095.064727] r10: 00000001 r9 : c6e06000 r8 : 00000179 [ 4095.064758] r7 : c6e07ca0 r6 : c73b8400 r5 : 00000000 r4 : c59a7d80 [ 4095.064758] r3 : 00000038 r2 : 00000800 r1 : 00000000 r0 : c7754fc0 [ 4095.064788] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel [ 4095.064819] Control: 10c5387d Table: 86cc804a DAC: 00000015 [ 4095.064849] [ 4095.064849] PC: 0xc01da528: [ 4095.064880] a528 0a000003 e3a05000 e1a00005 e24bd020 e89da9f0 e5951010 e3e06000 e14b22dc ..... [ 4095.070373] 7fe0: c00a48ac 00000013 00000000 c6e07ff8 c00a48ac c00c0a94 84752f09 60772177 [ 4095.070404] Backtrace: [ 4095.070465] [<c01da570>] (jbd2_journal_file_inode+0x0/0x118) from [<c01aeac0>] (mpage_da_map_and_submit+0x48c/0x618) [ 4095.070495] r7:c6e07ca0 r6:c6e07d00 r5:c6e07d90 r4:c7754fc0 [ 4095.070556] [<c01ae634>] (mpage_da_map_and_submit+0x0/0x618) from [<c01af40c>] (ext4_da_writepages+0x2a4/0x5c8) [ 4095.070617] [<c01af168>] (ext4_da_writepages+0x0/0x5c8) from [<c0112af4>] (do_writepages+0x34/0x40) [ 4095.070678] [<c0112ac0>] (do_writepages+0x0/0x40) from [<c01645a4>] (writeback_single_inode+0xd4/0x288) [ 4095.070709] [<c01644d0>] (writeback_single_inode+0x0/0x288) from [<c0164ed4>] (writeback_sb_inodes+0xb4/0x184) [ 4095.070770] [<c0164e20>] (writeback_sb_inodes+0x0/0x184) from [<c01655a0>] (writeback_inodes_wb+0xc4/0x13c) [ 4095.070831] [<c01654dc>] (writeback_inodes_wb+0x0/0x13c) from [<c01658f0>] (wb_writeback+0x2d8/0x464) [ 4095.070861] [<c0165618>] (wb_writeback+0x0/0x464) from [<c0165cb8>] (wb_do_writeback+0x23c/0x2c4) [ 4095.070922] [<c0165a7c>] (wb_do_writeback+0x0/0x2c4) from [<c0165df4>] (bdi_writeback_thread+0xb4/0x2dc) [ 4095.070953] [<c0165d40>] (bdi_writeback_thread+0x0/0x2dc) from [<c00c0b18>] (kthread+0x90/0x98) [ 4095.071014] [<c00c0a88>] (kthread+0x0/0x98) from [<c00a48ac>] (do_exit+0x0/0x72c) [ 4095.071044] r7:00000013 r6:c00a48ac r5:c00c0a88 r4:c78c7ec4 [ 4095.071105] Code: e89da8f0 e5963000 e3130002 1afffffa (e5913000) [ 4095.071166] ---[ end trace 7fe9f9b727e5cf78 ]--- [ 4095.071197] Kernel panic - not syncing: Fatal exception The probably reason of such behaviour is an inode opened in READ mode has been marked as 'dirty' somehow and written back by ext4_da_writepages. Cause jinode == NULL it could lead to the kernel panic. The patch prevents kernel panic and helps to investigate the problem providing an inode number. Change-Id: I1d77a011b580db682b8e2d122ef3d5e44e0ce5c7 Signed-off-by: Volodymyr Mieshkov <[email protected]> Signed-off-by: Pranav Vashi <[email protected]>

The filesystem layer expects pages in the block device's mapping to not be in highmem (the mapping's gfp mask is set in bdget()), but CMA can currently replace lowmem pages with highmem pages, leading to crashes in filesystem code such as the one below: Unable to handle kernel NULL pointer dereference at virtual address 00000400 pgd = c0c98000 [00000400] *pgd=00c91831, *pte=00000000, *ppte=00000000 Internal error: Oops: 817 [#1] PREEMPT SMP ARM CPU: 0 Not tainted (3.5.0-rc5+ #80) PC is at __memzero+0x24/0x80 ... Process fsstress (pid: 323, stack limit = 0xc0cbc2f0) Backtrace: [<c010e3f0>] (ext4_getblk+0x0/0x180) from [<c010e58c>] (ext4_bread+0x1c/0x98) [<c010e570>] (ext4_bread+0x0/0x98) from [<c0117944>] (ext4_mkdir+0x160/0x3bc) r4:c15337f0 [<c01177e4>] (ext4_mkdir+0x0/0x3bc) from [<c00c29e0>] (vfs_mkdir+0x8c/0x98) [<c00c2954>] (vfs_mkdir+0x0/0x98) from [<c00c2a60>] (sys_mkdirat+0x74/0xac) r6:00000000 r5:c152eb40 r4:000001ff r3:c14b43f0 [<c00c29ec>] (sys_mkdirat+0x0/0xac) from [<c00c2ab8>] (sys_mkdir+0x20/0x24) r6:beccdcf0 r5:00074000 r4:beccdbbc [<c00c2a98>] (sys_mkdir+0x0/0x24) from [<c000e3c0>] (ret_fast_syscall+0x0/0x30) Fix this by replacing only highmem pages with highmem. Change-Id: I6af2d509af48b5a586037be14bd3593b3f269d95 Reported-by: Laura Abbott <[email protected]> Signed-off-by: Rabin Vincent <[email protected]> Acked-by: Michal Nazarewicz <[email protected]> Signed-off-by: Marek Szyprowski <[email protected]> Signed-off-by: Laura Abbott <[email protected]>

This moves ARM over to the asm-generic/unaligned.h header. This has the benefit of better code generated especially for ARMv7 on gcc 4.7+ compilers. As Arnd Bergmann, points out: The asm-generic version uses the "struct" version for native-endian unaligned access and the "byteshift" version for the opposite endianess. The current ARM version however uses the "byteshift" implementation for both. Thanks to Nicolas Pitre for the excellent analysis: Test case: int foo (int *x) { return get_unaligned(x); } long long bar (long long *x) { return get_unaligned(x); } With the current ARM version: foo: ldrb r3, [r0, didhiy#2] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 2B], MEM[(const u8 *)x_1(D) + 2B] ldrb r1, [r0, didhiy#1] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 1B], MEM[(const u8 *)x_1(D) + 1B] ldrb r2, [r0, #0] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D)], MEM[(const u8 *)x_1(D)] mov r3, r3, asl #16 @ tmp154, MEM[(const u8 *)x_1(D) + 2B], ldrb r0, [r0, didhiy#3] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 3B], MEM[(const u8 *)x_1(D) + 3B] orr r3, r3, r1, asl coolya#8 @, tmp155, tmp154, MEM[(const u8 *)x_1(D) + 1B], orr r3, r3, r2 @ tmp157, tmp155, MEM[(const u8 *)x_1(D)] orr r0, r3, r0, asl #24 @,, tmp157, MEM[(const u8 *)x_1(D) + 3B], bx lr @ bar: stmfd sp!, {r4, r5, r6, r7} @, mov r2, #0 @ tmp184, ldrb r5, [r0, coolya#6] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 6B], MEM[(const u8 *)x_1(D) + 6B] ldrb r4, [r0, CyanogenMod#5] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 5B], MEM[(const u8 *)x_1(D) + 5B] ldrb ip, [r0, didhiy#2] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 2B], MEM[(const u8 *)x_1(D) + 2B] ldrb r1, [r0, didhiy#4] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 4B], MEM[(const u8 *)x_1(D) + 4B] mov r5, r5, asl #16 @ tmp175, MEM[(const u8 *)x_1(D) + 6B], ldrb r7, [r0, didhiy#1] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 1B], MEM[(const u8 *)x_1(D) + 1B] orr r5, r5, r4, asl coolya#8 @, tmp176, tmp175, MEM[(const u8 *)x_1(D) + 5B], ldrb r6, [r0, coolya#7] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 7B], MEM[(const u8 *)x_1(D) + 7B] orr r5, r5, r1 @ tmp178, tmp176, MEM[(const u8 *)x_1(D) + 4B] ldrb r4, [r0, #0] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D)], MEM[(const u8 *)x_1(D)] mov ip, ip, asl #16 @ tmp188, MEM[(const u8 *)x_1(D) + 2B], ldrb r1, [r0, didhiy#3] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 3B], MEM[(const u8 *)x_1(D) + 3B] orr ip, ip, r7, asl coolya#8 @, tmp189, tmp188, MEM[(const u8 *)x_1(D) + 1B], orr r3, r5, r6, asl #24 @,, tmp178, MEM[(const u8 *)x_1(D) + 7B], orr ip, ip, r4 @ tmp191, tmp189, MEM[(const u8 *)x_1(D)] orr ip, ip, r1, asl #24 @, tmp194, tmp191, MEM[(const u8 *)x_1(D) + 3B], mov r1, r3 @, orr r0, r2, ip @ tmp171, tmp184, tmp194 ldmfd sp!, {r4, r5, r6, r7} bx lr In both cases the code is slightly suboptimal. One may wonder why wasting r2 with the constant 0 in the second case for example. And all the mov's could be folded in subsequent orr's, etc. Now with the asm-generic version: foo: ldr r0, [r0, #0] @ unaligned @,* x bx lr @ bar: mov r3, r0 @ x, x ldr r0, [r0, #0] @ unaligned @,* x ldr r1, [r3, didhiy#4] @ unaligned @, bx lr @ This is way better of course, but only because this was compiled for ARMv7. In this case the compiler knows that the hardware can do unaligned word access. This isn't that obvious for foo(), but if we remove the get_unaligned() from bar as follows: long long bar (long long *x) {return *x; } then the resulting code is: bar: ldmia r0, {r0, r1} @ x,, bx lr @ So this proves that the presumed aligned vs unaligned cases does have influence on the instructions the compiler may use and that the above unaligned code results are not just an accident. Still... this isn't fully conclusive without at least looking at the resulting assembly fron a pre ARMv6 compilation. Let's see with an ARMv5 target: foo: ldrb r3, [r0, #0] @ zero_extendqisi2 @ tmp139,* x ldrb r1, [r0, didhiy#1] @ zero_extendqisi2 @ tmp140, ldrb r2, [r0, didhiy#2] @ zero_extendqisi2 @ tmp143, ldrb r0, [r0, didhiy#3] @ zero_extendqisi2 @ tmp146, orr r3, r3, r1, asl coolya#8 @, tmp142, tmp139, tmp140, orr r3, r3, r2, asl #16 @, tmp145, tmp142, tmp143, orr r0, r3, r0, asl #24 @,, tmp145, tmp146, bx lr @ bar: stmfd sp!, {r4, r5, r6, r7} @, ldrb r2, [r0, #0] @ zero_extendqisi2 @ tmp139,* x ldrb r7, [r0, didhiy#1] @ zero_extendqisi2 @ tmp140, ldrb r3, [r0, didhiy#4] @ zero_extendqisi2 @ tmp149, ldrb r6, [r0, CyanogenMod#5] @ zero_extendqisi2 @ tmp150, ldrb r5, [r0, didhiy#2] @ zero_extendqisi2 @ tmp143, ldrb r4, [r0, coolya#6] @ zero_extendqisi2 @ tmp153, ldrb r1, [r0, coolya#7] @ zero_extendqisi2 @ tmp156, ldrb ip, [r0, didhiy#3] @ zero_extendqisi2 @ tmp146, orr r2, r2, r7, asl coolya#8 @, tmp142, tmp139, tmp140, orr r3, r3, r6, asl coolya#8 @, tmp152, tmp149, tmp150, orr r2, r2, r5, asl #16 @, tmp145, tmp142, tmp143, orr r3, r3, r4, asl #16 @, tmp155, tmp152, tmp153, orr r0, r2, ip, asl #24 @,, tmp145, tmp146, orr r1, r3, r1, asl #24 @,, tmp155, tmp156, ldmfd sp!, {r4, r5, r6, r7} bx lr Compared to the initial results, this is really nicely optimized and I couldn't do much better if I were to hand code it myself. Signed-off-by: Rob Herring <[email protected]> Reviewed-by: Nicolas Pitre <[email protected]> Tested-by: Thomas Petazzoni <[email protected]> Reviewed-by: Arnd Bergmann <[email protected]> Signed-off-by: Russell King <[email protected]> modified for Mako from kernel.org reference Signed-off-by: faux123 <[email protected]> Conflicts: arch/arm/include/asm/unaligned.h Conflicts: arch/arm/include/asm/unaligned.h Conflicts: arch/arm/include/asm/Kbuild

ARM has some private syscalls (for example, set_tls(2)) which lie outside the range of NR_syscalls. If any of these are called while syscall tracing is being performed, out-of-bounds array access will occur in the ftrace and perf sys_{enter,exit} handlers. # trace-cmd record -e raw_syscalls:* true && trace-cmd report ... true-653 [000] 384.675777: sys_enter: NR 192 (0, 1000, 3, 4000022, ffffffff, 0) true-653 [000] 384.675812: sys_exit: NR 192 = 1995915264 true-653 [000] 384.675971: sys_enter: NR 983045 (76f74480, 76f74000, 76f74b28, 76f74480, 76f76f74, 1) true-653 [000] 384.675988: sys_exit: NR 983045 = 0 ... # trace-cmd record -e syscalls:* true [ 17.289329] Unable to handle kernel paging request at virtual address aaaaaace [ 17.289590] pgd = 9e71c000 [ 17.289696] [aaaaaace] *pgd=00000000 [ 17.289985] Internal error: Oops: 5 [didhiy#1] PREEMPT SMP ARM [ 17.290169] Modules linked in: [ 17.290391] CPU: 0 PID: 704 Comm: true Not tainted 3.18.0-rc2+ #21 [ 17.290585] task: 9f4dab00 ti: 9e710000 task.ti: 9e710000 [ 17.290747] PC is at ftrace_syscall_enter+0x48/0x1f8 [ 17.290866] LR is at syscall_trace_enter+0x124/0x184 Fix this by ignoring out-of-NR_syscalls-bounds syscall numbers. Commit cd0980f "tracing: Check invalid syscall nr while tracing syscalls" added the check for less than zero, but it should have also checked for greater than NR_syscalls. Link: http://lkml.kernel.org/p/[email protected] Fixes: cd0980f "tracing: Check invalid syscall nr while tracing syscalls" Cc: [email protected] # 2.6.33+ Signed-off-by: Rabin Vincent <[email protected]> Signed-off-by: Steven Rostedt <[email protected]> Conflicts: kernel/trace/trace_syscalls.c Change-Id: I512142f8f1e1b2a8dc063209666dbce9737377e7

…ssion() While running stress tests on adding and deleting ftrace instances I hit this bug: BUG: unable to handle kernel NULL pointer dereference at 0000000000000020 IP: selinux_inode_permission+0x85/0x160 PGD 63681067 PUD 7ddbe067 PMD 0 Oops: 0000 [#1] PREEMPT CPU: 0 PID: 5634 Comm: ftrace-test-mki Not tainted 3.13.0-rc4-test-00033-gd2a6dde-dirty #20 Hardware name: /DG965MQ, BIOS MQ96510J.86A.0372.2006.0605.1717 06/05/2006 task: ffff880078375800 ti: ffff88007ddb0000 task.ti: ffff88007ddb0000 RIP: 0010:[<ffffffff812d8bc5>] [<ffffffff812d8bc5>] selinux_inode_permission+0x85/0x160 RSP: 0018:ffff88007ddb1c48 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000800000 RCX: ffff88006dd43840 RDX: 0000000000000001 RSI: 0000000000000081 RDI: ffff88006ee46000 RBP: ffff88007ddb1c88 R08: 0000000000000000 R09: ffff88007ddb1c54 R10: 6e6576652f6f6f66 R11: 0000000000000003 R12: 0000000000000000 R13: 0000000000000081 R14: ffff88006ee46000 R15: 0000000000000000 FS: 00007f217b5b6700(0000) GS:ffffffff81e21000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033^M CR2: 0000000000000020 CR3: 000000006a0fe000 CR4: 00000000000007f0 Call Trace: security_inode_permission+0x1c/0x30 __inode_permission+0x41/0xa0 inode_permission+0x18/0x50 link_path_walk+0x66/0x920 path_openat+0xa6/0x6c0 do_filp_open+0x43/0xa0 do_sys_open+0x146/0x240 SyS_open+0x1e/0x20 system_call_fastpath+0x16/0x1b Code: 84 a1 00 00 00 81 e3 00 20 00 00 89 d8 83 c8 02 40 f6 c6 04 0f 45 d8 40 f6 c6 08 74 71 80 cf 02 49 8b 46 38 4c 8d 4d cc 45 31 c0 <0f> b7 50 20 8b 70 1c 48 8b 41 70 89 d9 8b 78 04 e8 36 cf ff ff RIP selinux_inode_permission+0x85/0x160 CR2: 0000000000000020 Investigating, I found that the inode->i_security was NULL, and the dereference of it caused the oops. in selinux_inode_permission(): isec = inode->i_security; rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd); Note, the crash came from stressing the deletion and reading of debugfs files. I was not able to recreate this via normal files. But I'm not sure they are safe. It may just be that the race window is much harder to hit. What seems to have happened (and what I have traced), is the file is being opened at the same time the file or directory is being deleted. As the dentry and inode locks are not held during the path walk, nor is the inodes ref counts being incremented, there is nothing saving these structures from being discarded except for an rcu_read_lock(). The rcu_read_lock() protects against freeing of the inode, but it does not protect freeing of the inode_security_struct. Now if the freeing of the i_security happens with a call_rcu(), and the i_security field of the inode is not changed (it gets freed as the inode gets freed) then there will be no issue here. (Linus Torvalds suggested not setting the field to NULL such that we do not need to check if it is NULL in the permission check). Note, this is a hack, but it fixes the problem at hand. A real fix is to restructure the destroy_inode() to call all the destructor handlers from the RCU callback. But that is a major job to do, and requires a lot of work. For now, we just band-aid this bug with this fix (it works), and work on a more maintainable solution in the future. Link: http://lkml.kernel.org/r/[email protected] Link: http://lkml.kernel.org/r/[email protected] Cc: [email protected] Signed-off-by: Steven Rostedt <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Change-Id: Iee13effc679858fa7503243f463e905f237dd92b

ARM has some private syscalls (for example, set_tls(2)) which lie outside the range of NR_syscalls. If any of these are called while syscall tracing is being performed, out-of-bounds array access will occur in the ftrace and perf sys_{enter,exit} handlers. # trace-cmd record -e raw_syscalls:* true && trace-cmd report ... true-653 [000] 384.675777: sys_enter: NR 192 (0, 1000, 3, 4000022, ffffffff, 0) true-653 [000] 384.675812: sys_exit: NR 192 = 1995915264 true-653 [000] 384.675971: sys_enter: NR 983045 (76f74480, 76f74000, 76f74b28, 76f74480, 76f76f74, 1) true-653 [000] 384.675988: sys_exit: NR 983045 = 0 ... # trace-cmd record -e syscalls:* true [ 17.289329] Unable to handle kernel paging request at virtual address aaaaaace [ 17.289590] pgd = 9e71c000 [ 17.289696] [aaaaaace] *pgd=00000000 [ 17.289985] Internal error: Oops: 5 [#1] PREEMPT SMP ARM [ 17.290169] Modules linked in: [ 17.290391] CPU: 0 PID: 704 Comm: true Not tainted 3.18.0-rc2+ #21 [ 17.290585] task: 9f4dab00 ti: 9e710000 task.ti: 9e710000 [ 17.290747] PC is at ftrace_syscall_enter+0x48/0x1f8 [ 17.290866] LR is at syscall_trace_enter+0x124/0x184 Fix this by ignoring out-of-NR_syscalls-bounds syscall numbers. Commit cd0980f "tracing: Check invalid syscall nr while tracing syscalls" added the check for less than zero, but it should have also checked for greater than NR_syscalls. Link: http://lkml.kernel.org/p/[email protected] Fixes: cd0980f "tracing: Check invalid syscall nr while tracing syscalls" Cc: [email protected] # 2.6.33+ Signed-off-by: Rabin Vincent <[email protected]> Signed-off-by: Steven Rostedt <[email protected]> Change-Id: Ie317d23826c2c9e4d380a2b44dc50747818a84e9

Setting an empty security context (length=0) on a file will lead to incorrectly dereferencing the type and other fields of the security context structure, yielding a kernel BUG. As a zero-length security context is never valid, just reject all such security contexts whether coming from userspace via setxattr or coming from the filesystem upon a getxattr request by SELinux. Setting a security context value (empty or otherwise) unknown to SELinux in the first place is only possible for a root process (CAP_MAC_ADMIN), and, if running SELinux in enforcing mode, only if the corresponding SELinux mac_admin permission is also granted to the domain by policy. In Fedora policies, this is only allowed for specific domains such as livecd for setting down security contexts that are not defined in the build host policy. [On Android, this can only be set by root/CAP_MAC_ADMIN processes, and if running SELinux in enforcing mode, only if mac_admin permission is granted in policy. In Android 4.4, this would only be allowed for root/CAP_MAC_ADMIN processes that are also in unconfined domains. In current AOSP master, mac_admin is not allowed for any domains except the recovery console which has a legitimate need for it. The other potential vector is mounting a maliciously crafted filesystem for which SELinux fetches xattrs (e.g. an ext4 filesystem on a SDcard). However, the end result is only a local denial-of-service (DOS) due to kernel BUG. This fix is queued for 3.14.] Reproducer: su setenforce 0 touch foo setfattr -n security.selinux foo Caveat: Relabeling or removing foo after doing the above may not be possible without booting with SELinux disabled. Any subsequent access to foo after doing the above will also trigger the BUG. BUG output from Matthew Thode: [ 473.893141] ------------[ cut here ]------------ [ 473.962110] kernel BUG at security/selinux/ss/services.c:654! [ 473.995314] invalid opcode: 0000 [coolya#6] SMP [ 474.027196] Modules linked in: [ 474.058118] CPU: 0 PID: 8138 Comm: ls Tainted: G D I 3.13.0-grsec #1 [ 474.116637] Hardware name: Supermicro X8ST3/X8ST3, BIOS 2.0 07/29/10 [ 474.149768] task: ffff8805f50cd010 ti: ffff8805f50cd488 task.ti: ffff8805f50cd488 [ 474.183707] RIP: 0010:[<ffffffff814681c7>] [<ffffffff814681c7>] context_struct_compute_av+0xce/0x308 [ 474.219954] RSP: 0018:ffff8805c0ac3c38 EFLAGS: 00010246 [ 474.252253] RAX: 0000000000000000 RBX: ffff8805c0ac3d94 RCX: 0000000000000100 [ 474.287018] RDX: ffff8805e8aac000 RSI: 00000000ffffffff RDI: ffff8805e8aaa000 [ 474.321199] RBP: ffff8805c0ac3cb8 R08: 0000000000000010 R09: 0000000000000006 [ 474.357446] R10: 0000000000000000 R11: ffff8805c567a000 R12: 0000000000000006 [ 474.419191] R13: ffff8805c2b74e88 R14: 00000000000001da R15: 0000000000000000 [ 474.453816] FS: 00007f2e75220800(0000) GS:ffff88061fc00000(0000) knlGS:0000000000000000 [ 474.489254] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 474.522215] CR2: 00007f2e74716090 CR3: 00000005c085e000 CR4: 00000000000207f0 [ 474.556058] Stack: [ 474.584325] ffff8805c0ac3c98 ffffffff811b549b ffff8805c0ac3c98 ffff8805f1190a40 [ 474.618913] ffff8805a6202f08 ffff8805c2b74e88 00068800d0464990 ffff8805e8aac860 [ 474.653955] ffff8805c0ac3cb8 000700068113833a ffff880606c75060 ffff8805c0ac3d94 [ 474.690461] Call Trace: [ 474.723779] [<ffffffff811b549b>] ? lookup_fast+0x1cd/0x22a [ 474.778049] [<ffffffff81468824>] security_compute_av+0xf4/0x20b [ 474.811398] [<ffffffff8196f419>] avc_compute_av+0x2a/0x179 [ 474.843813] [<ffffffff8145727b>] avc_has_perm+0x45/0xf4 [ 474.875694] [<ffffffff81457d0e>] inode_has_perm+0x2a/0x31 [ 474.907370] [<ffffffff81457e76>] selinux_inode_getattr+0x3c/0x3e [ 474.938726] [<ffffffff81455cf6>] security_inode_getattr+0x1b/0x22 [ 474.970036] [<ffffffff811b057d>] vfs_getattr+0x19/0x2d [ 475.000618] [<ffffffff811b05e5>] vfs_fstatat+0x54/0x91 [ 475.030402] [<ffffffff811b063b>] vfs_lstat+0x19/0x1b [ 475.061097] [<ffffffff811b077e>] SyS_newlstat+0x15/0x30 [ 475.094595] [<ffffffff8113c5c1>] ? __audit_syscall_entry+0xa1/0xc3 [ 475.148405] [<ffffffff8197791e>] system_call_fastpath+0x16/0x1b [ 475.179201] Code: 00 48 85 c0 48 89 45 b8 75 02 0f 0b 48 8b 45 a0 48 8b 3d 45 d0 b6 00 8b 40 08 89 c6 ff ce e8 d1 b0 06 00 48 85 c0 49 89 c7 75 02 <0f> 0b 48 8b 45 b8 4c 8b 28 eb 1e 49 8d 7d 08 be 80 01 00 00 e8 [ 475.255884] RIP [<ffffffff814681c7>] context_struct_compute_av+0xce/0x308 [ 475.296120] RSP <ffff8805c0ac3c38> [ 475.328734] ---[ end trace f076482e9d754adc ]--- [sds: commit message edited to note Android implications and to generate a unique Change-Id for gerrit] Reported-by: Matthew Thode <[email protected]> Signed-off-by: Stephen Smalley <[email protected]> Cc: [email protected] Signed-off-by: Paul Moore <[email protected]> Change-Id: I427391b56afdc5807b525961f2c1254b6d28973c

An issue was observed when a userspace task exits. The page which hits error here is the zero page. In binder mmap, the whole of vma is not mapped. On a task crash, when debuggerd reads the binder regions, the unmapped areas fall to do_anonymous_page in handle_pte_fault, due to the absence of a vm_fault handler. This results in zero page being mapped. Later in zap_pte_range, vm_normal_page returns zero page in the case of VM_MIXEDMAP and it results in the error. BUG: Bad page map in process mediaserver pte:9dff379f pmd:9bfbd831 page:c0ed8e60 count:1 mapcount:-1 mapping: (null) index:0x0 page flags: 0x404(referenced|reserved) addr:40c3f000 vm_flags:10220051 anon_vma: (null) mapping:d9fe0764 index:fd vma->vm_ops->fault: (null) vma->vm_file->f_op->mmap: binder_mmap+0x0/0x274 CPU: 0 PID: 1463 Comm: mediaserver Tainted: G W 3.10.17+ #1 [<c001549c>] (unwind_backtrace+0x0/0x11c) from [<c001200c>] (show_stack+0x10/0x14) [<c001200c>] (show_stack+0x10/0x14) from [<c0103d78>] (print_bad_pte+0x158/0x190) [<c0103d78>] (print_bad_pte+0x158/0x190) from [<c01055f0>] (unmap_single_vma+0x2e4/0x598) [<c01055f0>] (unmap_single_vma+0x2e4/0x598) from [<c010618c>] (unmap_vmas+0x34/0x50) [<c010618c>] (unmap_vmas+0x34/0x50) from [<c010a9e4>] (exit_mmap+0xc8/0x1e8) [<c010a9e4>] (exit_mmap+0xc8/0x1e8) from [<c00520f0>] (mmput+0x54/0xd0) [<c00520f0>] (mmput+0x54/0xd0) from [<c005972c>] (do_exit+0x360/0x990) [<c005972c>] (do_exit+0x360/0x990) from [<c0059ef0>] (do_group_exit+0x84/0xc0) [<c0059ef0>] (do_group_exit+0x84/0xc0) from [<c0066de0>] (get_signal_to_deliver+0x4d4/0x548) [<c0066de0>] (get_signal_to_deliver+0x4d4/0x548) from [<c0011500>] (do_signal+0xa8/0x3b8) Add a vm_fault handler which returns VM_FAULT_SIGBUS, and prevents the wrong fallback to do_anonymous_page. Change-Id: I43c227e489f74f4907f199caf99f571b61883064 Signed-off-by: Vinayak Menon <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

On the irq exit path, tick_nohz_irq_exit() may raise a softirq, which action leads to the wake up path and select_task_rq_fair() that makes use of rcu to iterate the domains. This is an illegal use of RCU because we may be in RCU extended quiescent state if we interrupted an RCU-idle window in the idle loop: [ 132.978883] =============================== [ 132.978883] [ INFO: suspicious RCU usage. ] [ 132.978883] ------------------------------- [ 132.978883] kernel/sched_fair.c:1707 suspicious rcu_dereference_check() usage! [ 132.978883] [ 132.978883] other info that might help us debug this: [ 132.978883] [ 132.978883] [ 132.978883] rcu_scheduler_active = 1, debug_locks = 0 [ 132.978883] RCU used illegally from extended quiescent state! [ 132.978883] 2 locks held by swapper/0: [ 132.978883] #0: (&p->pi_lock){-.-.-.}, at: [<ffffffff8105a729>] try_to_wake_up+0x39/0x2f0 [ 132.978883] #1: (rcu_read_lock){.+.+..}, at: [<ffffffff8105556a>] select_task_rq_fair+0x6a/0xec0 [ 132.978883] [ 132.978883] stack backtrace: [ 132.978883] Pid: 0, comm: swapper Tainted: G W 3.0.0+ #178 [ 132.978883] Call Trace: [ 132.978883] <IRQ> [<ffffffff810a01f6>] lockdep_rcu_suspicious+0xe6/0x100 [ 132.978883] [<ffffffff81055c49>] select_task_rq_fair+0x749/0xec0 [ 132.978883] [<ffffffff8105556a>] ? select_task_rq_fair+0x6a/0xec0 [ 132.978883] [<ffffffff812fe494>] ? do_raw_spin_lock+0x54/0x150 [ 132.978883] [<ffffffff810a1f2d>] ? trace_hardirqs_on+0xd/0x10 [ 132.978883] [<ffffffff8105a7c3>] try_to_wake_up+0xd3/0x2f0 [ 132.978883] [<ffffffff81094f98>] ? ktime_get+0x68/0xf0 [ 132.978883] [<ffffffff8105aa35>] wake_up_process+0x15/0x20 [ 132.978883] [<ffffffff81069dd5>] raise_softirq_irqoff+0x65/0x110 [ 132.978883] [<ffffffff8108eb65>] __hrtimer_start_range_ns+0x415/0x5a0 [ 132.978883] [<ffffffff812fe3ee>] ? do_raw_spin_unlock+0x5e/0xb0 [ 132.978883] [<ffffffff8108ed08>] hrtimer_start+0x18/0x20 [ 132.978883] [<ffffffff8109c9c3>] tick_nohz_stop_sched_tick+0x393/0x450 [ 132.978883] [<ffffffff810694f2>] irq_exit+0xd2/0x100 [ 132.978883] [<ffffffff81829e96>] do_IRQ+0x66/0xe0 [ 132.978883] [<ffffffff81820d53>] common_interrupt+0x13/0x13 [ 132.978883] <EOI> [<ffffffff8103434b>] ? native_safe_halt+0xb/0x10 [ 132.978883] [<ffffffff810a1f2d>] ? trace_hardirqs_on+0xd/0x10 [ 132.978883] [<ffffffff810144ea>] default_idle+0xba/0x370 [ 132.978883] [<ffffffff810147fe>] amd_e400_idle+0x5e/0x130 [ 132.978883] [<ffffffff8100a9f6>] cpu_idle+0xb6/0x120 [ 132.978883] [<ffffffff817f217f>] rest_init+0xef/0x150 [ 132.978883] [<ffffffff817f20e2>] ? rest_init+0x52/0x150 [ 132.978883] [<ffffffff81ed9cf3>] start_kernel+0x3da/0x3e5 [ 132.978883] [<ffffffff81ed9346>] x86_64_start_reservations+0x131/0x135 [ 132.978883] [<ffffffff81ed944d>] x86_64_start_kernel+0x103/0x112 Fix this by calling rcu_idle_enter() after tick_nohz_irq_exit(). Signed-off-by: Frederic Weisbecker <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Peter Zijlstra <[email protected]> Signed-off-by: Paul E. McKenney <[email protected]> Reviewed-by: Josh Triplett <[email protected]>

If a user key gets negatively instantiated, an error code is cached in the payload area. A negatively instantiated key may be then be positively instantiated by updating it with valid data. However, the ->update key type method must be aware that the error code may be there. The following may be used to trigger the bug in the user key type: keyctl request2 user user "" @U keyctl add user user "a" @U which manifests itself as: BUG: unable to handle kernel paging request at 00000000ffffff8a IP: [<ffffffff810a376f>] __call_rcu.constprop.76+0x1f/0x280 kernel/rcu/tree.c:3046 PGD 7cc30067 PUD 0 Oops: 0002 [#1] SMP Modules linked in: CPU: 3 PID: 2644 Comm: a.out Not tainted 4.3.0+ #49 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 task: ffff88003ddea700 ti: ffff88003dd88000 task.ti: ffff88003dd88000 RIP: 0010:[<ffffffff810a376f>] [<ffffffff810a376f>] __call_rcu.constprop.76+0x1f/0x280 [<ffffffff810a376f>] __call_rcu.constprop.76+0x1f/0x280 kernel/rcu/tree.c:3046 RSP: 0018:ffff88003dd8bdb0 EFLAGS: 00010246 RAX: 00000000ffffff82 RBX: 0000000000000000 RCX: 0000000000000001 RDX: ffffffff81e3fe40 RSI: 0000000000000000 RDI: 00000000ffffff82 RBP: ffff88003dd8bde0 R08: ffff88007d2d2da0 R09: 0000000000000000 R10: 0000000000000000 R11: ffff88003e8073c0 R12: 00000000ffffff82 R13: ffff88003dd8be68 R14: ffff88007d027600 R15: ffff88003ddea700 FS: 0000000000b92880(0063) GS:ffff88007fd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 00000000ffffff8a CR3: 000000007cc5f000 CR4: 00000000000006e0 Stack: ffff88003dd8bdf0 ffffffff81160a8a 0000000000000000 00000000ffffff82 ffff88003dd8be68 ffff88007d027600 ffff88003dd8bdf0 ffffffff810a39e5 ffff88003dd8be20 ffffffff812a31ab ffff88007d027600 ffff88007d027620 Call Trace: [<ffffffff810a39e5>] kfree_call_rcu+0x15/0x20 kernel/rcu/tree.c:3136 [<ffffffff812a31ab>] user_update+0x8b/0xb0 security/keys/user_defined.c:129 [< inline >] __key_update security/keys/key.c:730 [<ffffffff8129e5c1>] key_create_or_update+0x291/0x440 security/keys/key.c:908 [< inline >] SYSC_add_key security/keys/keyctl.c:125 [<ffffffff8129fc21>] SyS_add_key+0x101/0x1e0 security/keys/keyctl.c:60 [<ffffffff8185f617>] entry_SYSCALL_64_fastpath+0x12/0x6a arch/x86/entry/entry_64.S:185 Note the error code (-ENOKEY) in EDX. A similar bug can be tripped by: keyctl request2 trusted user "" @U keyctl add trusted user "a" @U This should also affect encrypted keys - but that has to be correctly parameterised or it will fail with EINVAL before getting to the bit that will crashes. Change-Id: I171d566f431c56208e1fe279f466d2d399a9ac7c Reported-by: Dmitry Vyukov <[email protected]> Signed-off-by: David Howells <[email protected]> Acked-by: Mimi Zohar <[email protected]> Signed-off-by: James Morris <[email protected]>

DerRomtester added 9 commits January 13, 2014 17:33

Toolchain path

9bee8ef

Makefile update

9053f56

makefile tests

e25f257

build script update

f50a0f8

Revert "makefile tests"

af69fab

This reverts commit e25f257.

makefile

d4fc48e

o3 seems working

ab5a9f4

hmm

1408751

arm: Added NEON compilation flag to VFP module

4f54719

didhiy added a commit that referenced this pull request Jan 15, 2014

Merge pull request #1 from DerRomtester/x-aries-cm-11.0

40b347b

X aries cm 11.0

didhiy merged commit 40b347b into didhiy:x-aries-cm-11.0 Jan 15, 2014

lgrootnoob referenced this pull request in lgrootnoob/android_kernel_samsung_aries Aug 6, 2015

restart sequential testing, boots. #1

336047d

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X aries cm 11.0 #1

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DerRomtester commented Jan 14, 2014

X aries cm 11.0 #1

X aries cm 11.0 #1

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DerRomtester commented Jan 14, 2014