INFO: task hung in acct

Status: upstream: reported C repro on 2021/02/03 06:45
Reported-by: syzbot+142da932e85a993bd6c1@syzkaller.appspotmail.com
First crash: 2000d, last: 1737d
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in acct kernel 1 C 1 314d 314d 0/29 auto-obsoleted due to no activity on 2025/12/25 18:56
linux-4.14 INFO: task hung in acct 1 1 1906d 1906d 0/1 auto-closed as invalid on 2021/09/05 08:45
▶ ▼ Fix bisection attempts (8)
Created Duration User Patch Repo Result
2021/11/23 09:46 11m bisect fix linux-4.19.y error job log
2021/09/22 23:46 43m bisect fix linux-4.19.y OK (0) job log log
2021/08/22 10:18 41m bisect fix linux-4.19.y OK (0) job log log
2021/07/23 09:43 34m bisect fix linux-4.19.y OK (0) job log log
2021/06/23 09:09 34m bisect fix linux-4.19.y OK (0) job log log
2021/05/24 08:10 42m bisect fix linux-4.19.y OK (0) job log log
2021/04/12 09:21 39m bisect fix linux-4.19.y OK (0) job log log
2021/03/13 07:49 35m bisect fix linux-4.19.y OK (0) job log log

Sample crash report:
autofs4:pid:8109:autofs_fill_super: called with bogus options
autofs4:pid:8110:autofs_fill_super: called with bogus options
autofs4:pid:8113:autofs_fill_super: called with bogus options
INFO: task syz-executor318:8112 blocked for more than 140 seconds.
      Not tainted 4.19.172-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor318 D28536  8112   8095 0x00000004
Call Trace:
 context_switch syzkaller/managers/linux-4-19/kernel/kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 syzkaller/managers/linux-4-19/kernel/kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 syzkaller/managers/linux-4-19/kernel/kernel/sched/core.c:3561
 schedule_preempt_disabled+0xf/0x20 syzkaller/managers/linux-4-19/kernel/kernel/sched/core.c:3619
 __mutex_lock_common syzkaller/managers/linux-4-19/kernel/kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x647/0x1260 syzkaller/managers/linux-4-19/kernel/kernel/locking/mutex.c:1072
 __do_sys_acct syzkaller/managers/linux-4-19/kernel/kernel/acct.c:285 [inline]
 __se_sys_acct+0x8c/0x930 syzkaller/managers/linux-4-19/kernel/kernel/acct.c:273
 do_syscall_64+0xf9/0x620 syzkaller/managers/linux-4-19/kernel/arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x43fc09
Code: Bad RIP value.
RSP: 002b:00007fff10542898 EFLAGS: 00000246 ORIG_RAX: 00000000000000a3
RAX: ffffffffffffffda RBX: 0030656c69662f2e RCX: 000000000043fc09
RDX: ffffffffffffffc0 RSI: 0000000000000000 RDI: 00000000200001c0
RBP: 0000000000000000 R08: 00007fff10542a38 R09: 00007fff10542a38
R10: 00007fff10542a38 R11: 0000000000000246 R12: 00007fff105428ac
R13: 431bde82d7b634db R14: 00000000004ad018 R15: 0000000000400488

Showing all locks held in the system:
1 lock held by khungtaskd/1566:
 #0: 00000000b8b1d31f (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 syzkaller/managers/linux-4-19/kernel/kernel/locking/lockdep.c:4440
1 lock held by in:imklog/7791:
 #0: 00000000890973f3 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 syzkaller/managers/linux-4-19/kernel/fs/file.c:767
1 lock held by syz-executor318/8111:
 #0: 00000000a098d295 (acct_on_mutex){+.+.}, at: __do_sys_acct syzkaller/managers/linux-4-19/kernel/kernel/acct.c:285 [inline]
 #0: 00000000a098d295 (acct_on_mutex){+.+.}, at: __se_sys_acct+0x8c/0x930 syzkaller/managers/linux-4-19/kernel/kernel/acct.c:273
1 lock held by syz-executor318/8112:
 #0: 00000000a098d295 (acct_on_mutex){+.+.}, at: __do_sys_acct syzkaller/managers/linux-4-19/kernel/kernel/acct.c:285 [inline]
 #0: 00000000a098d295 (acct_on_mutex){+.+.}, at: __se_sys_acct+0x8c/0x930 syzkaller/managers/linux-4-19/kernel/kernel/acct.c:273

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

NMI backtrace for cpu 1
CPU: 1 PID: 1566 Comm: khungtaskd Not tainted 4.19.172-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack syzkaller/managers/linux-4-19/kernel/lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2ef syzkaller/managers/linux-4-19/kernel/lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x63/0xa2 syzkaller/managers/linux-4-19/kernel/lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 syzkaller/managers/linux-4-19/kernel/lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace syzkaller/managers/linux-4-19/kernel/./include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks syzkaller/managers/linux-4-19/kernel/kernel/hung_task.c:203 [inline]
 watchdog+0x991/0xe60 syzkaller/managers/linux-4-19/kernel/kernel/hung_task.c:287
 kthread+0x33f/0x460 syzkaller/managers/linux-4-19/kernel/kernel/kthread.c:259
 ret_from_fork+0x24/0x30 syzkaller/managers/linux-4-19/kernel/arch/x86/entry/entry_64.S:415
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4681 Comm: systemd-journal Not tainted 4.19.172-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:trace_hardirqs_off+0x4/0x200 syzkaller/managers/linux-4-19/kernel/kernel/trace/trace_preemptirq.c:35
Code: ff 48 89 df e8 0d 90 30 00 eb 93 e8 06 90 30 00 e9 6a ff ff ff 4c 89 e7 e8 f9 8f 30 00 e9 34 ff ff ff 0f 1f 40 00 41 56 41 55 <41> 54 55 53 e8 63 d8 fa ff 65 8b 1d 4c ea 9a 7e 31 ff 89 de e8 c3
RSP: 0018:ffff8880a15779e0 EFLAGS: 00000082
RAX: 0000000000000286 RBX: 00000000006080c0 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffff8880a156c2e4
RBP: 00000000006080c0 R08: ffffffff8cd1b3c0 R09: 0000000000000000
R10: 0000000000000005 R11: 00000000d5f8e018 R12: 0000000000200000
R13: ffff88813bff04c0 R14: 0000000000000048 R15: ffff88813bff04c0
FS:  00007fda975f68c0(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fda949c6028 CR3: 00000000a1973000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 slab_alloc syzkaller/managers/linux-4-19/kernel/mm/slab.c:3388 [inline]
 kmem_cache_alloc_trace+0x9b/0x380 syzkaller/managers/linux-4-19/kernel/mm/slab.c:3623
 kmalloc syzkaller/managers/linux-4-19/kernel/./include/linux/slab.h:515 [inline]
 kzalloc syzkaller/managers/linux-4-19/kernel/./include/linux/slab.h:709 [inline]
 aa_alloc_file_ctx syzkaller/managers/linux-4-19/kernel/security/apparmor/include/file.h:60 [inline]
 apparmor_file_alloc_security+0x394/0xad0 syzkaller/managers/linux-4-19/kernel/security/apparmor/lsm.c:438
 security_file_alloc+0x40/0x90 syzkaller/managers/linux-4-19/kernel/security/security.c:880
 __alloc_file+0xc9/0x330 syzkaller/managers/linux-4-19/kernel/fs/file_table.c:105
 alloc_empty_file+0x6d/0x170 syzkaller/managers/linux-4-19/kernel/fs/file_table.c:150
 path_openat+0xe9/0x2df0 syzkaller/managers/linux-4-19/kernel/fs/namei.c:3526
 do_filp_open+0x18c/0x3f0 syzkaller/managers/linux-4-19/kernel/fs/namei.c:3567
 do_sys_open+0x3b3/0x520 syzkaller/managers/linux-4-19/kernel/fs/open.c:1085
 do_syscall_64+0xf9/0x620 syzkaller/managers/linux-4-19/kernel/arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fda96b86840
Code: 73 01 c3 48 8b 0d 68 77 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 bb 20 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24
RSP: 002b:00007ffc0a830d18 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007ffc0a831020 RCX: 00007fda96b86840
RDX: 00000000000001a0 RSI: 0000000000080042 RDI: 000056268a9fdc50
RBP: 000000000000000d R08: 000000000000c0ff R09: 00000000ffffffff
R10: 0000000000000069 R11: 0000000000000246 R12: 00000000ffffffff
R13: 000056268a9f1040 R14: 00007ffc0a830fe0 R15: 000056268a9fdca0

Crashes (9):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/02/11 07:49 linux-4.19.y 811218eceeaa a52ee10a .config console log report syz C ci2-linux-4-19 INFO: task hung in acct
2021/02/03 09:40 linux-4.19.y 811218eceeaa 624dad51 .config console log report syz C ci2-linux-4-19 INFO: task hung in acct
2021/10/24 09:46 linux-4.19.y 3f8a27f9e27b 282f03fb .config console log report info ci2-linux-4-19 INFO: task hung in acct
2021/10/20 05:53 linux-4.19.y 3f8a27f9e27b 466b7db1 .config console log report info ci2-linux-4-19 INFO: task hung in acct
2021/10/05 00:25 linux-4.19.y c2276d585654 ce697b49 .config console log report info ci2-linux-4-19 INFO: task hung in acct
2021/08/23 21:12 linux-4.19.y 59456c9cc40c b599f2fc .config console log report info ci2-linux-4-19 INFO: task hung in acct
2021/04/24 08:10 linux-4.19.y 2965db2e004c 17f0b706 .config console log report info ci2-linux-4-19 INFO: task hung in acct
2021/04/20 08:38 linux-4.19.y 2965db2e004c c0ced557 .config console log report info ci2-linux-4-19 INFO: task hung in acct
2021/02/03 06:44 linux-4.19.y 811218eceeaa 624dad51 .config console log report info ci2-linux-4-19 INFO: task hung in acct
* Struck through repros no longer work on HEAD.