decide if we should squash report-id field of OA reports, to reserve it. #24

rib · 2016-04-26T13:58:57Z

The status bits included in the report-id field of periodic OA reports aren't documented for Haswell, so we could potentially reserve this field for later use by explicitly zeroing it before copying it.

That said; while writting i-g-t tests I inferred that bit 10 of this field does seem to reliably indiciate that a report was timer triggered which is useful when trying to test the periodic sampling exponent.

If we don't reserve/zero the field then i-g-t can also verify that this field != 0 when testing if a report has landed somewhere (since zero is a valid value for all other fields).

I got the following stack trace under qemu: [ 7.575243] BUG: unable to handle kernel NULL pointer dereference at 0000000000000010 [ 7.596098] IP: [<ffffffff814f5b08>] cmos_set_alarm+0x38/0x280 [ 7.615699] PGD 3ccbe067 [ 7.615923] PUD 3daf2067 [ 7.635156] PMD 0 [ 7.654358] Oops: 0000 [rib#1] SMP [ 7.673869] Modules linked in: [ 7.693235] CPU: 0 PID: 1701 Comm: hwclock Tainted: G W 4.9.0-rc1+ rib#24 [ 7.712455] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014 [ 7.753569] task: ffff88003d88dc40 task.stack: ffffc90000224000 [ 7.773743] RIP: 0010:[<ffffffff814f5b08>] [<ffffffff814f5b08>] cmos_set_alarm+0x38/0x280 [ 7.794893] RSP: 0018:ffffc90000227c10 EFLAGS: 00010296 [ 7.815890] RAX: 000000000000001d RBX: ffffc90000227d28 RCX: ffffffff8182be78 [ 7.836057] RDX: 0000000000000001 RSI: 0000000000000202 RDI: 0000000000000202 [ 7.856612] RBP: ffffc90000227c48 R08: 0000000000000000 R09: 0000000000000001 [ 7.877561] R10: 00000000000001c0 R11: 00000000000001c0 R12: 0000000000000000 [ 7.897072] R13: ffff88003d96f400 R14: ffff88003dac6410 R15: ffff88003dac6420 [ 7.917403] FS: 00007f77f42d9700(0000) GS:ffff88003fc00000(0000) knlGS:0000000000000000 [ 7.938293] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 7.958364] CR2: 0000000000000010 CR3: 000000003ccbb000 CR4: 00000000000006f0 [ 7.978028] Stack: [ 7.997120] ffff88003dac6000 ffff88003dac6410 0000000058049d01 ffffc90000227d28 [ 8.016993] ffff88003dac6000 ffff88003dac6410 ffff88003dac6420 ffffc90000227c98 [ 8.039505] ffffffff814f225d 0000001800227c98 000000090000002a 0000000900000011 [ 8.059985] Call Trace: [ 8.080110] [<ffffffff814f225d>] __rtc_set_alarm+0x8d/0xa0 [ 8.099421] [<ffffffff814f2389>] rtc_timer_enqueue+0x119/0x190 [ 8.119925] [<ffffffff814f2e6e>] rtc_update_irq_enable+0xbe/0x100 [ 8.140583] [<ffffffff814f3bb0>] rtc_dev_ioctl+0x3c0/0x480 [ 8.161162] [<ffffffff81146b6a>] ? user_path_at_empty+0x3a/0x50 [ 8.182717] [<ffffffff8114aa36>] do_vfs_ioctl+0x96/0x5c0 [ 8.204624] [<ffffffff8113e066>] ? vfs_stat+0x16/0x20 [ 8.225994] [<ffffffff8113e135>] ? SyS_newstat+0x15/0x30 [ 8.247043] [<ffffffff8114afa7>] SyS_ioctl+0x47/0x80 [ 8.267191] [<ffffffff815f5c77>] entry_SYSCALL_64_fastpath+0x1a/0xa9 [ 8.288719] Code: 6a 81 48 89 e5 41 57 41 56 41 55 49 89 fd 41 54 53 48 89 f3 48 c7 c6 20 c4 78 81 48 83 ec 10 e8 8f 00 ef ff 4d 8b a5 a0 00 00 00 <41> 8b 44 24 10 85 c0 0f 8e 2b 02 00 00 4c 89 ef 31 c0 b9 53 01 [ 8.335233] RIP [<ffffffff814f5b08>] cmos_set_alarm+0x38/0x280 [ 8.357096] RSP <ffffc90000227c10> [ 8.379051] CR2: 0000000000000010 [ 8.401736] ---[ end trace 5cbcd83a1f225ed3 ]--- This occur only when CONFIG_DEBUG_TEST_DRIVER_REMOVE is enabled and CONFIG_RTC_DRV_CMOS builtin. When cmos_set_alarm() is called dev is NULL and so trigger the deref via cmos->irq The problem comes from that the device is removed but no remove function are called due to _exit_p(). This patch remove all _exit_p() annotation. Signed-off-by: Corentin Labbe <[email protected]> Signed-off-by: Alexandre Belloni <[email protected]>

The data_mutex is initialized too late, as it is needed for each device driver's power control, causing an OOPS: dvb-usb: found a 'TerraTec/qanu USB2.0 Highspeed DVB-T Receiver' in warm state. BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff846617af>] __mutex_lock_slowpath+0x6f/0x100 PGD 0 Oops: 0002 [rib#1] SMP Modules linked in: dvb_usb_cinergyT2(+) dvb_usb CPU: 0 PID: 2029 Comm: modprobe Not tainted 4.9.0-rc4-dvbmod rib#24 Hardware name: FUJITSU LIFEBOOK A544/FJNBB35 , BIOS Version 1.17 05/09/2014 task: ffff88020e943840 task.stack: ffff8801f36ec000 RIP: 0010:[<ffffffff846617af>] [<ffffffff846617af>] __mutex_lock_slowpath+0x6f/0x100 RSP: 0018:ffff8801f36efb10 EFLAGS: 00010282 RAX: 0000000000000000 RBX: ffff88021509bdc8 RCX: 00000000c0000100 RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff88021509bdcc RBP: ffff8801f36efb58 R08: ffff88021f216320 R09: 0000000000100000 R10: ffff88021f216320 R11: 00000023fee6c5a1 R12: ffff88020e943840 R13: ffff88021509bdcc R14: 00000000ffffffff R15: ffff88021509bdd0 FS: 00007f21adb86740(0000) GS:ffff88021f200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000215bce000 CR4: 00000000001406f0 Call Trace: mutex_lock+0x16/0x25 cinergyt2_power_ctrl+0x1f/0x60 [dvb_usb_cinergyT2] dvb_usb_device_init+0x21e/0x5d0 [dvb_usb] cinergyt2_usb_probe+0x21/0x50 [dvb_usb_cinergyT2] usb_probe_interface+0xf3/0x2a0 driver_probe_device+0x208/0x2b0 __driver_attach+0x87/0x90 driver_probe_device+0x2b0/0x2b0 bus_for_each_dev+0x52/0x80 bus_add_driver+0x1a3/0x220 driver_register+0x56/0xd0 usb_register_driver+0x77/0x130 do_one_initcall+0x46/0x180 free_vmap_area_noflush+0x38/0x70 kmem_cache_alloc+0x84/0xc0 do_init_module+0x50/0x1be load_module+0x1d8b/0x2100 find_symbol_in_section+0xa0/0xa0 SyS_finit_module+0x89/0x90 entry_SYSCALL_64_fastpath+0x13/0x94 Code: e8 a7 1d 00 00 8b 03 83 f8 01 0f 84 97 00 00 00 48 8b 43 10 4c 8d 7b 08 48 89 63 10 4c 89 3c 24 41 be ff ff ff ff 48 89 44 24 08 <48> 89 20 4c 89 64 24 10 eb 1a 49 c7 44 24 08 02 00 00 00 c6 43 RIP [<ffffffff846617af>] __mutex_lock_slowpath+0x6f/0x100 RSP <ffff8801f36efb10> CR2: 0000000000000000 So, move it to the struct dvb_usb_device and initialize it before calling the driver's callbacks. Reported-by: Jörg Otte <[email protected]> Tested-by: Jörg Otte <[email protected]> Signed-off-by: Mauro Carvalho Chehab <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>

As Eric Dumazet pointed out this also needs to be fixed in IPv6. v2: Contains the IPv6 tcp/Ipv6 dccp patches as well. We have seen a few incidents lately where a dst_enty has been freed with a dangling TCP socket reference (sk->sk_dst_cache) pointing to that dst_entry. If the conditions/timings are right a crash then ensues when the freed dst_entry is referenced later on. A Common crashing back trace is: #8 [] page_fault at ffffffff8163e648 [exception RIP: __tcp_ack_snd_check+74] . . #9 [] tcp_rcv_established at ffffffff81580b64 #10 [] tcp_v4_do_rcv at ffffffff8158b54a #11 [] tcp_v4_rcv at ffffffff8158cd02 #12 [] ip_local_deliver_finish at ffffffff815668f4 #13 [] ip_local_deliver at ffffffff81566bd9 #14 [] ip_rcv_finish at ffffffff8156656d #15 [] ip_rcv at ffffffff81566f06 #16 [] __netif_receive_skb_core at ffffffff8152b3a2 #17 [] __netif_receive_skb at ffffffff8152b608 #18 [] netif_receive_skb at ffffffff8152b690 #19 [] vmxnet3_rq_rx_complete at ffffffffa015eeaf [vmxnet3] #20 [] vmxnet3_poll_rx_only at ffffffffa015f32a [vmxnet3] #21 [] net_rx_action at ffffffff8152bac2 #22 [] __do_softirq at ffffffff81084b4f #23 [] call_softirq at ffffffff8164845c #24 [] do_softirq at ffffffff81016fc5 #25 [] irq_exit at ffffffff81084ee5 torvalds#26 [] do_IRQ at ffffffff81648ff8 Of course it may happen with other NIC drivers as well. It's found the freed dst_entry here: 224 static bool tcp_in_quickack_mode(struct sock *sk)↩ 225 {↩ 226 ▹ const struct inet_connection_sock *icsk = inet_csk(sk);↩ 227 ▹ const struct dst_entry *dst = __sk_dst_get(sk);↩ 228 ↩ 229 ▹ return (dst && dst_metric(dst, RTAX_QUICKACK)) ||↩ 230 ▹ ▹ (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong);↩ 231 }↩ But there are other backtraces attributed to the same freed dst_entry in netfilter code as well. All the vmcores showed 2 significant clues: - Remote hosts behind the default gateway had always been redirected to a different gateway. A rtable/dst_entry will be added for that host. Making more dst_entrys with lower reference counts. Making this more probable. - All vmcores showed a postitive LockDroppedIcmps value, e.g: LockDroppedIcmps 267 A closer look at the tcp_v4_err() handler revealed that do_redirect() will run regardless of whether user space has the socket locked. This can result in a race condition where the same dst_entry cached in sk->sk_dst_entry can be decremented twice for the same socket via: do_redirect()->__sk_dst_check()-> dst_release(). Which leads to the dst_entry being prematurely freed with another socket pointing to it via sk->sk_dst_cache and a subsequent crash. To fix this skip do_redirect() if usespace has the socket locked. Instead let the redirect take place later when user space does not have the socket locked. The dccp/IPv6 code is very similar in this respect, so fixing it there too. As Eric Garver pointed out the following commit now invalidates routes. Which can set the dst->obsolete flag so that ipv4_dst_check() returns null and triggers the dst_release(). Fixes: ceb3320 ("ipv4: Kill routes during PMTU/redirect updates.") Cc: Eric Garver <[email protected]> Cc: Hannes Sowa <[email protected]> Signed-off-by: Jon Maxwell <[email protected]> Signed-off-by: David S. Miller <[email protected]>

The following warning can be triggered by hot-unplugging the CPU on which an active SCHED_DEADLINE task is running on: ------------[ cut here ]------------ WARNING: CPU: 7 PID: 0 at kernel/sched/sched.h:833 replenish_dl_entity+0x71e/0xc40 rq->clock_update_flags < RQCF_ACT_SKIP CPU: 7 PID: 0 Comm: swapper/7 Tainted: G B 4.11.0-rc1+ #24 Hardware name: LENOVO ThinkCentre M8500t-N000/SHARKBAY, BIOS FBKTC1AUS 02/16/2016 Call Trace: <IRQ> dump_stack+0x85/0xc4 __warn+0x172/0x1b0 warn_slowpath_fmt+0xb4/0xf0 ? __warn+0x1b0/0x1b0 ? debug_check_no_locks_freed+0x2c0/0x2c0 ? cpudl_set+0x3d/0x2b0 replenish_dl_entity+0x71e/0xc40 enqueue_task_dl+0x2ea/0x12e0 ? dl_task_timer+0x777/0x990 ? __hrtimer_run_queues+0x270/0xa50 dl_task_timer+0x316/0x990 ? enqueue_task_dl+0x12e0/0x12e0 ? enqueue_task_dl+0x12e0/0x12e0 __hrtimer_run_queues+0x270/0xa50 ? hrtimer_cancel+0x20/0x20 ? hrtimer_interrupt+0x119/0x600 hrtimer_interrupt+0x19c/0x600 ? trace_hardirqs_off+0xd/0x10 local_apic_timer_interrupt+0x74/0xe0 smp_apic_timer_interrupt+0x76/0xa0 apic_timer_interrupt+0x93/0xa0 The DL task will be migrated to a suitable later deadline rq once the DL timer fires and currnet rq is offline. The rq clock of the new rq should be updated. This patch fixes it by updating the rq clock after holding the new rq's rq lock. Signed-off-by: Wanpeng Li <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Reviewed-by: Matt Fleming <[email protected]> Cc: Juri Lelli <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Mike Galbraith <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>

[ Upstream commit 45caeaa ] As Eric Dumazet pointed out this also needs to be fixed in IPv6. v2: Contains the IPv6 tcp/Ipv6 dccp patches as well. We have seen a few incidents lately where a dst_enty has been freed with a dangling TCP socket reference (sk->sk_dst_cache) pointing to that dst_entry. If the conditions/timings are right a crash then ensues when the freed dst_entry is referenced later on. A Common crashing back trace is: rib#8 [] page_fault at ffffffff8163e648 [exception RIP: __tcp_ack_snd_check+74] . . rib#9 [] tcp_rcv_established at ffffffff81580b64 rib#10 [] tcp_v4_do_rcv at ffffffff8158b54a rib#11 [] tcp_v4_rcv at ffffffff8158cd02 rib#12 [] ip_local_deliver_finish at ffffffff815668f4 rib#13 [] ip_local_deliver at ffffffff81566bd9 rib#14 [] ip_rcv_finish at ffffffff8156656d rib#15 [] ip_rcv at ffffffff81566f06 rib#16 [] __netif_receive_skb_core at ffffffff8152b3a2 rib#17 [] __netif_receive_skb at ffffffff8152b608 rib#18 [] netif_receive_skb at ffffffff8152b690 rib#19 [] vmxnet3_rq_rx_complete at ffffffffa015eeaf [vmxnet3] rib#20 [] vmxnet3_poll_rx_only at ffffffffa015f32a [vmxnet3] rib#21 [] net_rx_action at ffffffff8152bac2 rib#22 [] __do_softirq at ffffffff81084b4f rib#23 [] call_softirq at ffffffff8164845c rib#24 [] do_softirq at ffffffff81016fc5 rib#25 [] irq_exit at ffffffff81084ee5 torvalds#26 [] do_IRQ at ffffffff81648ff8 Of course it may happen with other NIC drivers as well. It's found the freed dst_entry here: 224 static bool tcp_in_quickack_mode(struct sock *sk)↩ 225 {↩ 226 ▹ const struct inet_connection_sock *icsk = inet_csk(sk);↩ 227 ▹ const struct dst_entry *dst = __sk_dst_get(sk);↩ 228 ↩ 229 ▹ return (dst && dst_metric(dst, RTAX_QUICKACK)) ||↩ 230 ▹ ▹ (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong);↩ 231 }↩ But there are other backtraces attributed to the same freed dst_entry in netfilter code as well. All the vmcores showed 2 significant clues: - Remote hosts behind the default gateway had always been redirected to a different gateway. A rtable/dst_entry will be added for that host. Making more dst_entrys with lower reference counts. Making this more probable. - All vmcores showed a postitive LockDroppedIcmps value, e.g: LockDroppedIcmps 267 A closer look at the tcp_v4_err() handler revealed that do_redirect() will run regardless of whether user space has the socket locked. This can result in a race condition where the same dst_entry cached in sk->sk_dst_entry can be decremented twice for the same socket via: do_redirect()->__sk_dst_check()-> dst_release(). Which leads to the dst_entry being prematurely freed with another socket pointing to it via sk->sk_dst_cache and a subsequent crash. To fix this skip do_redirect() if usespace has the socket locked. Instead let the redirect take place later when user space does not have the socket locked. The dccp/IPv6 code is very similar in this respect, so fixing it there too. As Eric Garver pointed out the following commit now invalidates routes. Which can set the dst->obsolete flag so that ipv4_dst_check() returns null and triggers the dst_release(). Fixes: ceb3320 ("ipv4: Kill routes during PMTU/redirect updates.") Cc: Eric Garver <[email protected]> Cc: Hannes Sowa <[email protected]> Signed-off-by: Jon Maxwell <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>

Preemption can occur during cancel preemption timer, and there will be inconsistent status in lapic, vmx and vmcs field. CPU0 CPU1 preemption timer vmexit handle_preemption_timer(vCPU0) kvm_lapic_expired_hv_timer vmx_cancel_hv_timer vmx->hv_deadline_tsc = -1 vmcs_clear_bits /* hv_timer_in_use still true */ sched_out sched_in kvm_arch_vcpu_load vmx_set_hv_timer write vmx->hv_deadline_tsc vmcs_set_bits /* back in kvm_lapic_expired_hv_timer */ hv_timer_in_use = false ... vmx_vcpu_run vmx_arm_hv_run write preemption timer deadline spurious preemption timer vmexit handle_preemption_timer(vCPU0) kvm_lapic_expired_hv_timer WARN_ON(!apic->lapic_timer.hv_timer_in_use); This can be reproduced sporadically during boot of L2 on a preemptible L1, causing a splat on L1. WARNING: CPU: 3 PID: 1952 at arch/x86/kvm/lapic.c:1529 kvm_lapic_expired_hv_timer+0xb5/0xd0 [kvm] CPU: 3 PID: 1952 Comm: qemu-system-x86 Not tainted 4.12.0-rc1+ rib#24 RIP: 0010:kvm_lapic_expired_hv_timer+0xb5/0xd0 [kvm] Call Trace: handle_preemption_timer+0xe/0x20 [kvm_intel] vmx_handle_exit+0xc9/0x15f0 [kvm_intel] ? lock_acquire+0xdb/0x250 ? lock_acquire+0xdb/0x250 ? kvm_arch_vcpu_ioctl_run+0xdf3/0x1ce0 [kvm] kvm_arch_vcpu_ioctl_run+0xe55/0x1ce0 [kvm] kvm_vcpu_ioctl+0x384/0x7b0 [kvm] ? kvm_vcpu_ioctl+0x384/0x7b0 [kvm] ? __fget+0xf3/0x210 do_vfs_ioctl+0xa4/0x700 ? __fget+0x114/0x210 SyS_ioctl+0x79/0x90 do_syscall_64+0x8f/0x750 ? trace_hardirqs_on_thunk+0x1a/0x1c entry_SYSCALL64_slow_path+0x25/0x25 This patch fixes it by disabling preemption while cancelling preemption timer. This way cancel_hv_timer is atomic with respect to kvm_arch_vcpu_load. Cc: Paolo Bonzini <[email protected]> Cc: Radim Krčmář <[email protected]> Signed-off-by: Wanpeng Li <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>

pfkey_broadcast() might be called from non process contexts, we can not use GFP_KERNEL in these cases [1]. This patch partially reverts commit ba51b6b ("net: Fix RCU splat in af_key"), only keeping the GFP_ATOMIC forcing under rcu_read_lock() section. [1] : syzkaller reported : in_atomic(): 1, irqs_disabled(): 0, pid: 2932, name: syzkaller183439 3 locks held by syzkaller183439/2932: #0: (&net->xfrm.xfrm_cfg_mutex){+.+.+.}, at: [<ffffffff83b43888>] pfkey_sendmsg+0x4c8/0x9f0 net/key/af_key.c:3649 rib#1: (&pfk->dump_lock){+.+.+.}, at: [<ffffffff83b467f6>] pfkey_do_dump+0x76/0x3f0 net/key/af_key.c:293 rib#2: (&(&net->xfrm.xfrm_policy_lock)->rlock){+...+.}, at: [<ffffffff83957632>] spin_lock_bh include/linux/spinlock.h:304 [inline] rib#2: (&(&net->xfrm.xfrm_policy_lock)->rlock){+...+.}, at: [<ffffffff83957632>] xfrm_policy_walk+0x192/0xa30 net/xfrm/xfrm_policy.c:1028 CPU: 0 PID: 2932 Comm: syzkaller183439 Not tainted 4.13.0-rc4+ rib#24 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:52 ___might_sleep+0x2b2/0x470 kernel/sched/core.c:5994 __might_sleep+0x95/0x190 kernel/sched/core.c:5947 slab_pre_alloc_hook mm/slab.h:416 [inline] slab_alloc mm/slab.c:3383 [inline] kmem_cache_alloc+0x24b/0x6e0 mm/slab.c:3559 skb_clone+0x1a0/0x400 net/core/skbuff.c:1037 pfkey_broadcast_one+0x4b2/0x6f0 net/key/af_key.c:207 pfkey_broadcast+0x4ba/0x770 net/key/af_key.c:281 dump_sp+0x3d6/0x500 net/key/af_key.c:2685 xfrm_policy_walk+0x2f1/0xa30 net/xfrm/xfrm_policy.c:1042 pfkey_dump_sp+0x42/0x50 net/key/af_key.c:2695 pfkey_do_dump+0xaa/0x3f0 net/key/af_key.c:299 pfkey_spddump+0x1a0/0x210 net/key/af_key.c:2722 pfkey_process+0x606/0x710 net/key/af_key.c:2814 pfkey_sendmsg+0x4d6/0x9f0 net/key/af_key.c:3650 sock_sendmsg_nosec net/socket.c:633 [inline] sock_sendmsg+0xca/0x110 net/socket.c:643 ___sys_sendmsg+0x755/0x890 net/socket.c:2035 __sys_sendmsg+0xe5/0x210 net/socket.c:2069 SYSC_sendmsg net/socket.c:2080 [inline] SyS_sendmsg+0x2d/0x50 net/socket.c:2076 entry_SYSCALL_64_fastpath+0x1f/0xbe RIP: 0033:0x445d79 RSP: 002b:00007f32447c1dc8 EFLAGS: 00000202 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000445d79 RDX: 0000000000000000 RSI: 000000002023dfc8 RDI: 0000000000000008 RBP: 0000000000000086 R08: 00007f32447c2700 R09: 00007f32447c2700 R10: 00007f32447c2700 R11: 0000000000000202 R12: 0000000000000000 R13: 00007ffe33edec4f R14: 00007f32447c29c0 R15: 0000000000000000 Fixes: ba51b6b ("net: Fix RCU splat in af_key") Signed-off-by: Eric Dumazet <[email protected]> Reported-by: Dmitry Vyukov <[email protected]> Cc: David Ahern <[email protected]> Acked-by: David Ahern <[email protected]> Signed-off-by: David S. Miller <[email protected]>

Jakub forgot to either use nlmsg_len() or nlmsg_msg_size(), allowing KMSAN to detect a possible uninit-value in rtnl_stats_get BUG: KMSAN: uninit-value in rtnl_stats_get+0x6d9/0x11d0 net/core/rtnetlink.c:4997 CPU: 0 PID: 10428 Comm: syz-executor034 Not tainted 5.1.0-rc2+ rib#24 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x173/0x1d0 lib/dump_stack.c:113 kmsan_report+0x131/0x2a0 mm/kmsan/kmsan.c:619 __msan_warning+0x7a/0xf0 mm/kmsan/kmsan_instr.c:310 rtnl_stats_get+0x6d9/0x11d0 net/core/rtnetlink.c:4997 rtnetlink_rcv_msg+0x115b/0x1550 net/core/rtnetlink.c:5192 netlink_rcv_skb+0x431/0x620 net/netlink/af_netlink.c:2485 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:5210 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline] netlink_unicast+0xf3e/0x1020 net/netlink/af_netlink.c:1336 netlink_sendmsg+0x127f/0x1300 net/netlink/af_netlink.c:1925 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg net/socket.c:632 [inline] ___sys_sendmsg+0xdb3/0x1220 net/socket.c:2137 __sys_sendmsg net/socket.c:2175 [inline] __do_sys_sendmsg net/socket.c:2184 [inline] __se_sys_sendmsg+0x305/0x460 net/socket.c:2182 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2182 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 Fixes: 51bc860 ("rtnetlink: stats: validate attributes in get as well as dumps") Signed-off-by: Eric Dumazet <[email protected]> Reported-by: syzbot <[email protected]> Cc: Jakub Kicinski <[email protected]> Signed-off-by: David S. Miller <[email protected]>

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decide if we should squash report-id field of OA reports, to reserve it. #24

decide if we should squash report-id field of OA reports, to reserve it. #24

rib commented Apr 26, 2016

decide if we should squash report-id field of OA reports, to reserve it. #24

decide if we should squash report-id field of OA reports, to reserve it. #24

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rib commented Apr 26, 2016