syzbot


INFO: task hung in tipc_exit_net (3)

Status: auto-obsoleted due to no activity on 2023/03/21 07:46
Reported-by: syzbot+60588a58826447a4fc9b@syzkaller.appspotmail.com
First crash: 467d, last: 457d
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 INFO: task hung in tipc_exit_net (2) 2 793d 807d 0/1 auto-closed as invalid on 2022/04/19 05:05
linux-4.14 INFO: task hung in tipc_exit_net 8 1018d 1104d 0/1 auto-closed as invalid on 2021/09/06 01:04
linux-4.19 INFO: task hung in tipc_exit_net C 523 353d 1188d 0/1 upstream: reported C repro on 2020/11/20 02:47
upstream INFO: task hung in tipc_exit_net tipc 2 1264d 1268d 0/26 auto-closed as invalid on 2020/12/03 19:41

Sample crash report:
netlink: 12 bytes leftover after parsing attributes in process `syz-executor.0'.
Bluetooth: hci5 command 0x0409 tx timeout
Bluetooth: hci5 command 0x041b tx timeout
Bluetooth: hci5 command 0x040f tx timeout
Bluetooth: hci5 command 0x0419 tx timeout
INFO: task kworker/u4:0:5 blocked for more than 140 seconds.
      Not tainted 4.14.299-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u4:0    D26960     5      2 0x80000000
Workqueue: netns cleanup_net
Call Trace:
 context_switch kernel/sched/core.c:2811 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3387
 schedule+0x8d/0x1b0 kernel/sched/core.c:3431
 schedule_timeout+0x80a/0xe90 kernel/time/timer.c:1724
 do_wait_for_common kernel/sched/completion.c:91 [inline]
 __wait_for_common kernel/sched/completion.c:112 [inline]
 wait_for_common+0x272/0x430 kernel/sched/completion.c:123
 flush_workqueue+0x3ce/0x1310 kernel/workqueue.c:2677
 flush_scheduled_work include/linux/workqueue.h:578 [inline]
 tipc_exit_net+0x38/0x60 net/tipc/core.c:96
 ops_exit_list+0xad/0x160 net/core/net_namespace.c:142
 cleanup_net+0x3b3/0x840 net/core/net_namespace.c:487
 process_one_work+0x793/0x14a0 kernel/workqueue.c:2117
 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2251
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:406

Showing all locks held in the system:
3 locks held by kworker/u4:0/5:
 #0:  ("%s""netns"){+.+.}, at: [<ffffffff81365eb0>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2088
 #1:  (net_cleanup_work){+.+.}, at: [<ffffffff81365ee6>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2092
 #2:  (net_mutex){+.+.}, at: [<ffffffff85c21df0>] cleanup_net+0x110/0x840 net/core/net_namespace.c:453
1 lock held by khungtaskd/1533:
 #0:  (tasklist_lock){.+.+}, at: [<ffffffff8702a1b9>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548
2 locks held by kworker/1:2/3437:
 #0:  ("events"){+.+.}, at: [<ffffffff81365eb0>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2088
 #1:  ((&m->wq)){+.+.}, at: [<ffffffff81365ee6>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2092
1 lock held by in:imklog/7688:
 #0:  (&f->f_pos_lock){+.+.}, at: [<ffffffff818d8b5b>] __fdget_pos+0x1fb/0x2b0 fs/file.c:819
1 lock held by syz-executor.1/3540:
 #0:  (net_mutex){+.+.}, at: [<ffffffff85c22676>] copy_net_ns+0x156/0x440 net/core/net_namespace.c:413

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

NMI backtrace for cpu 0
CPU: 0 PID: 1533 Comm: khungtaskd Not tainted 4.14.299-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
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:406
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 8 Comm: rcu_preempt Not tainted 4.14.299-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
task: ffff8880b540e200 task.stack: ffff8880b5418000
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:779 [inline]
RIP: 0010:lock_release+0x41e/0x870 kernel/locking/lockdep.c:4020
RSP: 0018:ffff8880b541fb68 EFLAGS: 00000086
RAX: 1ffffffff11e13d9 RBX: 1ffff11016a83f70 RCX: 1ffff11016a81d51
RDX: dffffc0000000000 RSI: 0000000000000001 RDI: 0000000000000086
RBP: ffff8880b540e200 R08: ffffffff8b9c0420 R09: 0000000000000000
R10: 0000000000000000 R11: ffff8880b540e200 R12: 0000000000000000
R13: 0000000000000003 R14: ffff8880b540e200 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbe46d81000 CR3: 00000000a14a8000 CR4: 00000000003406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:158 [inline]
 _raw_spin_unlock_irqrestore+0x1b/0xe0 kernel/locking/spinlock.c:192
 try_to_del_timer_sync+0xaf/0xe0 kernel/time/timer.c:1183
 del_timer_sync+0x17c/0x240 kernel/time/timer.c:1246
 schedule_timeout+0x4b7/0xe90 kernel/time/timer.c:1748
 rcu_gp_kthread+0xc0a/0x1e60 kernel/rcu/tree.c:2255
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:406
Code: 85 84 08 00 00 00 00 00 00 48 c1 e8 03 80 3c 10 00 0f 85 88 03 00 00 48 83 3d 26 bd ae 07 00 0f 84 ba 01 00 00 48 8b 3c 24 57 9d <0f> 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 48 c7 04 03 00 00 

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/11/21 07:46 linux-4.14.y e911713e40ca 5bb70014 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-4-14 INFO: task hung in tipc_exit_net
2022/11/14 10:30 linux-4.14.y e911713e40ca 943f4cb8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-4-14 INFO: task hung in tipc_exit_net
2022/11/10 18:41 linux-4.14.y e911713e40ca 3ead01ad .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-4-14 INFO: task hung in tipc_exit_net
* Struck through repros no longer work on HEAD.