syzbot


INFO: task \k[sCY

Status: auto-obsoleted due to no activity on 2025/11/24 06:37
Subsystems: usb
[Documentation on labels]
First crash: 146d, last: 146d

Sample crash report:
INFO: task ôª\k[sC®Ö˜›Y
I}:19298 blocked for more than 143 seconds.
      Not tainted 6.17.0-rc1-syzkaller-00224-g8d561baae505 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:ôª\k[sC®Ö˜›Y
I} state:D stack:28392 pid:19298 tgid:19297 ppid:18749  task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7058
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
 __mutex_lock_common kernel/locking/mutex.c:676 [inline]
 __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760
 device_lock include/linux/device.h:911 [inline]
 usbdev_open+0x16e/0x760 drivers/usb/core/devio.c:1054
 chrdev_open+0x4c9/0x5e0 fs/char_dev.c:414
 do_dentry_open+0x950/0x13f0 fs/open.c:965
 vfs_open+0x3b/0x340 fs/open.c:1095
 do_open fs/namei.c:3887 [inline]
 path_openat+0x2ee5/0x3830 fs/namei.c:4046
 do_filp_open+0x1fa/0x410 fs/namei.c:4073
 do_sys_openat2+0x121/0x1c0 fs/open.c:1435
 do_sys_open fs/open.c:1450 [inline]
 __do_sys_openat fs/open.c:1466 [inline]
 __se_sys_openat fs/open.c:1461 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1461
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5b3b38d550
RSP: 002b:00007f5b3c2c0b70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000189800 RCX: 00007f5b3b38d550
RDX: 0000000000189800 RSI: 00007f5b3c2c0c10 RDI: 00000000ffffff9c
RBP: 00007f5b3c2c0c10 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd
R13: 00007f5b3b5b6038 R14: 00007f5b3b5b5fa0 R15: 00007f5b3b6dfa28
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.17.0-rc1-syzkaller-00224-g8d561baae505 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
 watchdog+0xf93/0xfe0 kernel/hung_task.c:491
 kthread+0x70e/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 21214 Comm: syz.1.3945 Not tainted 6.17.0-rc1-syzkaller-00224-g8d561baae505 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:unwind_next_frame+0x173c/0x2390 arch/x86/kernel/unwind_orc.c:648
Code: e8 89 0c 00 00 e9 f7 01 00 00 48 8b 54 24 08 48 8d 5a 02 48 83 c2 03 48 89 d8 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 19 0b 00 00 <48> 89 d0 48 c1 e8 03 0f b6 04 28 84 c0 0f 85 2b 0b 00 00 48 0f bf
RSP: 0018:ffffc9000c087058 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffffff906a522a RCX: 0000000000000000
RDX: ffffffff906a522b RSI: 0000000000000001 RDI: ffffc9000c087188
RBP: dffffc0000000000 R08: ffffc9000c087187 R09: 0000000000000000
R10: ffffc9000c087178 R11: fffff52001810e31 R12: ffffc9000c087a70
R13: ffffc9000c087178 R14: ffffc9000c087128 R15: 1ffffffff20d4a45
FS:  00007fd9c6bf66c0(0000) GS:ffff888125d1b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055558558b5c8 CR3: 000000006ec92000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000000c DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:388 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:405
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __do_kmalloc_node mm/slub.c:4365 [inline]
 __kmalloc_noprof+0x27a/0x4f0 mm/slub.c:4377
 vb2_core_allocated_buffers_storage drivers/media/common/videobuf2/videobuf2-core.c:855 [inline]
 vb2_core_reqbufs+0x97f/0x1420 drivers/media/common/videobuf2/videobuf2-core.c:934
 __vb2_init_fileio+0x318/0xff0 drivers/media/common/videobuf2/videobuf2-core.c:2895
 vb2_core_poll+0x4c1/0x840 drivers/media/common/videobuf2/videobuf2-core.c:2729
 vb2_poll drivers/media/common/videobuf2/videobuf2-v4l2.c:979 [inline]
 vb2_fop_poll+0x168/0x380 drivers/media/common/videobuf2/videobuf2-v4l2.c:1244
 v4l2_poll+0x147/0x2c0 drivers/media/v4l2-core/v4l2-dev.c:350
 vfs_poll include/linux/poll.h:82 [inline]
 io_file_supports_nowait io_uring/rw.c:46 [inline]
 __io_read+0x4b1/0x14f0 io_uring/rw.c:927
 io_read+0x1c/0x60 io_uring/rw.c:1020
 __io_issue_sqe+0x17e/0x4b0 io_uring/io_uring.c:1773
 io_issue_sqe+0x165/0xfd0 io_uring/io_uring.c:1796
 io_queue_sqe io_uring/io_uring.c:2025 [inline]
 io_req_task_submit+0x10b/0x1d0 io_uring/io_uring.c:1415
 io_handle_tw_list+0x34d/0x4c0 io_uring/io_uring.c:1102
 tctx_task_work_run+0x99/0x370 io_uring/io_uring.c:1167
 tctx_task_work+0x3f/0x90 io_uring/io_uring.c:1185
 task_work_run+0x1d4/0x260 kernel/task_work.c:227
 get_signal+0x11ed/0x1340 kernel/signal.c:2807
 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x75/0x110 kernel/entry/common.c:40
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd9c898ebe9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd9c6bf6038 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa
RAX: 0000000000001000 RBX: 00007fd9c8bb5fa0 RCX: 00007fd9c898ebe9
RDX: 0000000000000000 RSI: 00000000000847ba RDI: 0000000000000006
RBP: 00007fd9c8a11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000000e R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd9c8bb6038 R14: 00007fd9c8bb5fa0 R15: 00007fd9c8cdfa28
 </TASK>
----------------
Code disassembly (best guess):
   0:	e8 89 0c 00 00       	call   0xc8e
   5:	e9 f7 01 00 00       	jmp    0x201
   a:	48 8b 54 24 08       	mov    0x8(%rsp),%rdx
   f:	48 8d 5a 02          	lea    0x2(%rdx),%rbx
  13:	48 83 c2 03          	add    $0x3,%rdx
  17:	48 89 d8             	mov    %rbx,%rax
  1a:	48 c1 e8 03          	shr    $0x3,%rax
  1e:	0f b6 04 28          	movzbl (%rax,%rbp,1),%eax
  22:	84 c0                	test   %al,%al
  24:	0f 85 19 0b 00 00    	jne    0xb43
* 2a:	48 89 d0             	mov    %rdx,%rax <-- trapping instruction
  2d:	48 c1 e8 03          	shr    $0x3,%rax
  31:	0f b6 04 28          	movzbl (%rax,%rbp,1),%eax
  35:	84 c0                	test   %al,%al
  37:	0f 85 2b 0b 00 00    	jne    0xb68
  3d:	48                   	rex.W
  3e:	0f                   	.byte 0xf
  3f:	bf                   	.byte 0xbf

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/08/18 05:23 upstream 8d561baae505 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task \k[sCY
* Struck through repros no longer work on HEAD.