syzbot


BUG: unable to handle kernel NULL pointer dereference in vivid_stop_generating_vid_cap

Status: upstream: reported syz repro on 2019/09/25 17:35
Reported-by: syzbot+7250431a239fc633b813@syzkaller.appspotmail.com
First crash: 1726d, last: 1462d
Fix bisection the fix commit could be any of (bisect log):
  f6e27dbb1afa Linux 4.14.146
  56dfe6252c68 Linux 4.14.188
  
Last patch testing requests (2)
Created Duration User Patch Repo Result
2023/01/26 09:32 11m retest repro linux-4.14.y report log
2022/09/08 06:27 9m retest repro linux-4.14.y report log
Fix bisection attempts (8)
Created Duration User Patch Repo Result
2020/07/15 12:54 37m bisect fix linux-4.14.y job log (2)
2020/06/15 12:13 28m bisect fix linux-4.14.y job log (0) log
2020/05/16 11:42 30m bisect fix linux-4.14.y job log (0) log
2020/04/16 11:13 28m bisect fix linux-4.14.y job log (0) log
2020/03/17 10:45 28m bisect fix linux-4.14.y job log (0) log
2020/02/16 10:17 27m bisect fix linux-4.14.y job log (0) log
2020/01/17 09:18 27m bisect fix linux-4.14.y job log (0) log
2019/12/18 08:32 26m bisect fix linux-4.14.y job log (0) log

Sample crash report:
IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_0: link becomes ready
IPv6: ADDRCONF(NETDEV_UP): veth1_to_team: link is not ready
IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready
IPv6: ADDRCONF(NETDEV_CHANGE): team0: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_team: link becomes ready
BUG: unable to handle kernel NULL pointer dereference at 0000000000000020
IP: atomic_inc arch/x86/include/asm/atomic.h:92 [inline]
IP: kthread_stop+0x4c/0x650 kernel/kthread.c:525
PGD 7fccd067 P4D 7fccd067 PUD 8ba1a067 PMD 0 
Oops: 0002 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 0 PID: 6909 Comm: syz-executor.3 Not tainted 4.14.146 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff88809a6ba640 task.stack: ffff888097208000
RIP: 0010:atomic_inc arch/x86/include/asm/atomic.h:92 [inline]
RIP: 0010:kthread_stop+0x4c/0x650 kernel/kthread.c:525
RSP: 0018:ffff88809720fb50 EFLAGS: 00010297
RAX: ffff88809a6ba640 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000000000282
RBP: ffff88809720fb70 R08: ffff88809a6ba640 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff888099c83c70 R14: ffff888099c83c68 R15: ffffffff89bbfda0
FS:  000055555666c940(0000) GS:ffff8880aee00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000020 CR3: 000000009fb88000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 vivid_stop_generating_vid_cap+0x1b9/0x664 drivers/media/platform/vivid/vivid-kthread-cap.c:934
 vid_cap_stop_streaming+0x7c/0xd0 drivers/media/platform/vivid/vivid-vid-cap.c:273
 __vb2_queue_cancel+0xa3/0x890 drivers/media/v4l2-core/videobuf2-core.c:1655
 vb2_core_streamoff+0x52/0x110 drivers/media/v4l2-core/videobuf2-core.c:1788
 __vb2_cleanup_fileio+0x78/0x150 drivers/media/v4l2-core/videobuf2-core.c:2313
 vb2_core_queue_release+0x1d/0x80 drivers/media/v4l2-core/videobuf2-core.c:2040
 vb2_queue_release drivers/media/v4l2-core/videobuf2-v4l2.c:669 [inline]
 _vb2_fop_release+0x1cf/0x2a0 drivers/media/v4l2-core/videobuf2-v4l2.c:840
 vb2_fop_release+0x75/0xc0 drivers/media/v4l2-core/videobuf2-v4l2.c:854
 vivid_fop_release+0x180/0x3f0 drivers/media/platform/vivid/vivid-core.c:486
 v4l2_release+0xf9/0x190 drivers/media/v4l2-core/v4l2-dev.c:446
 __fput+0x275/0x7a0 fs/file_table.c:210
 ____fput+0x16/0x20 fs/file_table.c:244
 task_work_run+0x114/0x190 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 exit_to_usermode_loop+0x1da/0x220 arch/x86/entry/common.c:164
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
 do_syscall_64+0x4bc/0x640 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x413711
RSP: 002b:00007ffdf43c3060 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000413711
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004
RBP: 0000000000000001 R08: ffffffffffffffff R09: ffffffffffffffff
R10: 00007ffdf43c3140 R11: 0000000000000293 R12: 000000000075c9a0
R13: 000000000075c9a0 R14: 0000000000761c20 R15: 000000000075bfd4
Code: 00 65 8b 1d 67 59 c3 7e 83 fb 3f 0f 87 5e 04 00 00 e8 19 bb 1e 00 89 db 48 0f a3 1d ff 24 e7 06 0f 82 47 03 00 00 e8 04 bb 1e 00 <f0> 41 ff 44 24 20 49 8d 7c 24 24 48 b8 00 00 00 00 00 fc ff df 
RIP: atomic_inc arch/x86/include/asm/atomic.h:92 [inline] RSP: ffff88809720fb50
RIP: kthread_stop+0x4c/0x650 kernel/kthread.c:525 RSP: ffff88809720fb50
CR2: 0000000000000020
IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_1: link becomes ready
---[ end trace 412df94b1d9bcb57 ]---

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/09/25 17:36 linux-4.14.y f6e27dbb1afa a3355dba .config console log report syz ci2-linux-4-14
2019/11/05 14:27 linux-4.14.y ddef1e8e3f6e af5c522d .config console log report ci2-linux-4-14
2019/09/25 16:34 linux-4.14.y f6e27dbb1afa a3355dba .config console log report ci2-linux-4-14
* Struck through repros no longer work on HEAD.