syzbot


INFO: task hung in acct

Status: auto-closed as invalid on 2021/09/05 08:45
Reported-by: syzbot+884fe5c2243392110a0e@syzkaller.appspotmail.com
First crash: 1077d, last: 1077d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: task hung in acct C error 9 908d 1171d 0/1 upstream: reported C repro on 2021/02/03 06:45

Sample crash report:
VPS: Can't find an adfs filesystem on dev nullb0.
VPS: Can't find an adfs filesystem on dev nullb0.
BFS-fs: bfs_fill_super(): Inode 0x00000002 corrupted
Bluetooth: hci5 command 0x0406 tx timeout
Bluetooth: hci1 command 0x0406 tx timeout
INFO: task syz-executor.2:10408 blocked for more than 140 seconds.
      Not tainted 4.14.232-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D29320 10408  10063 0x00000000
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3384
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3486
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893
 SYSC_acct kernel/acct.c:285 [inline]
 SyS_acct+0x65/0x850 kernel/acct.c:273
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x4665f9
RSP: 002b:00007f3f91395188 EFLAGS: 00000246 ORIG_RAX: 00000000000000a3
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000100
RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007ffc08f2744f R14: 00007f3f91395300 R15: 0000000000022000
INFO: task syz-executor.1:14081 blocked for more than 140 seconds.
      Not tainted 4.14.232-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.1  D28520 14081  10428 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3384
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3486
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893
 SYSC_acct kernel/acct.c:285 [inline]
 SyS_acct+0x65/0x850 kernel/acct.c:273
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x4665f9
RSP: 002b:00007fea79854188 EFLAGS: 00000246 ORIG_RAX: 00000000000000a3
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000040
RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007fffb47d1a6f R14: 00007fea79854300 R15: 0000000000022000
INFO: task syz-executor.1:14088 blocked for more than 140 seconds.
      Not tainted 4.14.232-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.1  D29096 14088  10428 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3384
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3486
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893
 SYSC_acct kernel/acct.c:285 [inline]
 SyS_acct+0x65/0x850 kernel/acct.c:273
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x4665f9
RSP: 002b:00007fea79833188 EFLAGS: 00000246 ORIG_RAX: 00000000000000a3
RAX: ffffffffffffffda RBX: 000000000056c008 RCX: 00000000004665f9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000040
RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c008
R13: 00007fffb47d1a6f R14: 00007fea79833300 R15: 0000000000022000

Showing all locks held in the system:
1 lock held by khungtaskd/1533:
 #0:  (tasklist_lock){.+.+}, at: [<ffffffff8700b7b7>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548
1 lock held by syz-executor.2/10399:
 #0:  (acct_on_mutex){+.+.}, at: [<ffffffff814e02c5>] SYSC_acct kernel/acct.c:285 [inline]
 #0:  (acct_on_mutex){+.+.}, at: [<ffffffff814e02c5>] SyS_acct+0x65/0x850 kernel/acct.c:273
1 lock held by syz-executor.2/10408:
 #0:  (acct_on_mutex){+.+.}, at: [<ffffffff814e02c5>] SYSC_acct kernel/acct.c:285 [inline]
 #0:  (acct_on_mutex){+.+.}, at: [<ffffffff814e02c5>] SyS_acct+0x65/0x850 kernel/acct.c:273
1 lock held by syz-executor.1/14081:
 #0:  (acct_on_mutex){+.+.}, at: [<ffffffff814e02c5>] SYSC_acct kernel/acct.c:285 [inline]
 #0:  (acct_on_mutex){+.+.}, at: [<ffffffff814e02c5>] SyS_acct+0x65/0x850 kernel/acct.c:273
1 lock held by syz-executor.1/14088:
 #0:  (acct_on_mutex){+.+.}, at: [<ffffffff814e02c5>] SYSC_acct kernel/acct.c:285 [inline]
 #0:  (acct_on_mutex){+.+.}, at: [<ffffffff814e02c5>] SyS_acct+0x65/0x850 kernel/acct.c:273

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 1533 Comm: khungtaskd Not tainted 4.14.232-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x13a/0x180 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline]
 watchdog+0x5b9/0xb40 kernel/hung_task.c:274
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4624 Comm: systemd-journal Not tainted 4.14.232-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8880a16aa140 task.stack: ffff8880a16b0000
RIP: 0010:unwind_get_return_address arch/x86/kernel/unwind_orc.c:252 [inline]
RIP: 0010:unwind_get_return_address+0x48/0x90 arch/x86/kernel/unwind_orc.c:247
RSP: 0018:ffff8880a16b7b18 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: ffff8880a16b7b40 RCX: 0000000000000000
RDX: 1ffff110142d6f71 RSI: ffff8880a16b7a30 RDI: ffff8880a16b7b40
RBP: ffff8880a16b7b88 R08: 0000000000000001 R09: 0000000000000001
R10: ffff8880a16b7f58 R11: 0000000000000001 R12: ffff8880a16b7bc0
R13: 0000000000000000 R14: fffffffffffffffe R15: 00005584bfa042f0
FS:  00007f64e4f678c0(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f64e2439000 CR3: 00000000a1509000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __save_stack_trace+0xa0/0x160 arch/x86/kernel/stacktrace.c:45
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0xc3/0x1a0 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3496 [inline]
 kmem_cache_free+0x7c/0x2b0 mm/slab.c:3758
 putname+0xcd/0x110 fs/namei.c:259
 do_sys_open+0x203/0x410 fs/open.c:1090
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7f64e44f6840
RSP: 002b:00007ffdd0fbf0e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007ffdd0fbf3f0 RCX: 00007f64e44f6840
RDX: 00000000000001a0 RSI: 0000000000080042 RDI: 00005584bfa042f0
RBP: 000000000000000d R08: 0000000000000000 R09: 00000000ffffffff
R10: 0000000000000069 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00005584bf9f7040 R14: 00007ffdd0fbf3b0 R15: 00005584bf9fcc30
Code: 04 3c 03 7e 51 8b 03 85 c0 75 05 5b 31 c0 5d c3 48 8d 6b 48 48 b8 00 00 00 00 00 fc ff df 48 89 ea 48 c1 ea 03 80 3c 02 00 75 32 <48> 8b 7b 48 e8 9f a2 13 00 85 c0 74 d3 48 b8 00 00 00 00 00 fc 

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/05/08 08:45 linux-4.14.y 7d7d1c0ab3eb bc5434be .config console log report info ci2-linux-4-14 INFO: task hung in acct
* Struck through repros no longer work on HEAD.