syzbot


INFO: task hung in cleanup_net (4)

Status: auto-closed as invalid on 2020/11/17 15:39
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 773d, last: 769d
similar bugs (10):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in cleanup_net (2) 2 1250d 1251d 0/24 closed as invalid on 2019/05/08 13:05
android-44 INFO: task hung in cleanup_net 10 1204d 1246d 0/2 auto-closed as invalid on 2019/10/25 08:38
upstream INFO: task hung in cleanup_net 1 1755d 1743d 3/24 fixed on 2018/01/03 02:35
linux-4.19 INFO: task hung in cleanup_net 1 869d 869d 0/1 auto-closed as invalid on 2020/09/08 00:00
linux-4.14 INFO: task hung in cleanup_net C inconclusive 23 257d 1263d 0/1 upstream: reported C repro on 2019/04/13 10:16
upstream INFO: task hung in cleanup_net (3) 1 1185d 1185d 0/24 auto-closed as invalid on 2019/10/25 14:21
android-49 INFO: task hung in cleanup_net 4 1254d 1262d 0/3 auto-closed as invalid on 2019/10/18 21:44
android-414 INFO: task hung in cleanup_net C 45 1123d 1265d 0/1 public: reported C repro on 2019/04/11 00:00
android-49 INFO: task hung in cleanup_net (2) 1 1038d 1038d 0/3 auto-closed as invalid on 2020/03/23 02:35
upstream INFO: task hung in cleanup_net (5) 3 495d 541d 0/24 auto-closed as invalid on 2021/09/03 11:33

Sample crash report:
INFO: task kworker/u4:1:32426 blocked for more than 143 seconds.
      Not tainted 5.9.0-rc1-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:1    state:D stack:27184 pid:32426 ppid:     2 flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
 context_switch kernel/sched/core.c:3778 [inline]
 __schedule+0x8e5/0x21e0 kernel/sched/core.c:4527
 schedule+0xd0/0x2a0 kernel/sched/core.c:4602
 rwsem_down_read_slowpath+0x2f7/0xc90 kernel/locking/rwsem.c:1099
 __down_read kernel/locking/rwsem.c:1341 [inline]
 down_read+0x1ec/0x420 kernel/locking/rwsem.c:1494
 cleanup_net+0x9b/0xa00 net/core/net_namespace.c:565
 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415
 kthread+0x3b5/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
INFO: task syz-executor.4:884 blocked for more than 143 seconds.
      Not tainted 5.9.0-rc1-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.4  state:D stack:29464 pid:  884 ppid:  7238 flags:0x20020004
Call Trace:
 context_switch kernel/sched/core.c:3778 [inline]
 __schedule+0x8e5/0x21e0 kernel/sched/core.c:4527
 schedule+0xd0/0x2a0 kernel/sched/core.c:4602
 rwsem_down_write_slowpath+0x603/0xc60 kernel/locking/rwsem.c:1235
 __down_write kernel/locking/rwsem.c:1389 [inline]
 down_write+0x137/0x150 kernel/locking/rwsem.c:1532
 register_netdevice_notifier+0x1e/0x260 net/core/dev.c:1814
 raw_init+0x296/0x340 net/can/raw.c:339
 can_create+0x27c/0x4d0 net/can/af_can.c:168
 __sock_create+0x3ca/0x740 net/socket.c:1427
 sock_create net/socket.c:1478 [inline]
 __sys_socket+0xef/0x200 net/socket.c:1520
 __do_sys_socket net/socket.c:1529 [inline]
 __se_sys_socket net/socket.c:1527 [inline]
 __ia32_sys_socket+0x6f/0xb0 net/socket.c:1527
 do_syscall_32_irqs_on arch/x86/entry/common.c:84 [inline]
 __do_fast_syscall_32+0x57/0x80 arch/x86/entry/common.c:126
 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:149
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7fb3549
Code: Bad RIP value.
RSP: 002b:00000000f55ad0cc EFLAGS: 00000296 ORIG_RAX: 0000000000000167
RAX: ffffffffffffffda RBX: 000000000000001d RCX: 0000000000000003
RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor.4:909 blocked for more than 143 seconds.
      Not tainted 5.9.0-rc1-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.4  state:D stack:29824 pid:  909 ppid:  7238 flags:0x20024004
Call Trace:
 context_switch kernel/sched/core.c:3778 [inline]
 __schedule+0x8e5/0x21e0 kernel/sched/core.c:4527
 schedule+0xd0/0x2a0 kernel/sched/core.c:4602
 rwsem_down_write_slowpath+0x603/0xc60 kernel/locking/rwsem.c:1235
 __down_write kernel/locking/rwsem.c:1389 [inline]
 down_write+0x137/0x150 kernel/locking/rwsem.c:1532
 register_netdevice_notifier+0x1e/0x260 net/core/dev.c:1814
 bcm_init+0x1a3/0x210 net/can/bcm.c:1451
 can_create+0x27c/0x4d0 net/can/af_can.c:168
 __sock_create+0x3ca/0x740 net/socket.c:1427
 sock_create net/socket.c:1478 [inline]
 __sys_socket+0xef/0x200 net/socket.c:1520
 __do_sys_socket net/socket.c:1529 [inline]
 __se_sys_socket net/socket.c:1527 [inline]
 __ia32_sys_socket+0x6f/0xb0 net/socket.c:1527
 do_syscall_32_irqs_on arch/x86/entry/common.c:84 [inline]
 __do_fast_syscall_32+0x57/0x80 arch/x86/entry/common.c:126
 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:149
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7fb3549
Code: Bad RIP value.
RSP: 002b:00000000f558c0cc EFLAGS: 00000296 ORIG_RAX: 0000000000000167
RAX: ffffffffffffffda RBX: 000000000000001d RCX: 0000000000000002
RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor.4:920 blocked for more than 144 seconds.
      Not tainted 5.9.0-rc1-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.4  state:D stack:29704 pid:  920 ppid:  7238 flags:0x20020004
Call Trace:
 context_switch kernel/sched/core.c:3778 [inline]
 __schedule+0x8e5/0x21e0 kernel/sched/core.c:4527
 schedule+0xd0/0x2a0 kernel/sched/core.c:4602
 rwsem_down_write_slowpath+0x603/0xc60 kernel/locking/rwsem.c:1235
 __down_write kernel/locking/rwsem.c:1389 [inline]
 down_write+0x137/0x150 kernel/locking/rwsem.c:1532
 register_netdevice_notifier+0x1e/0x260 net/core/dev.c:1814
 raw_init+0x296/0x340 net/can/raw.c:339
 can_create+0x27c/0x4d0 net/can/af_can.c:168
 __sock_create+0x3ca/0x740 net/socket.c:1427
 sock_create net/socket.c:1478 [inline]
 __sys_socket+0xef/0x200 net/socket.c:1520
 __do_sys_socket net/socket.c:1529 [inline]
 __se_sys_socket net/socket.c:1527 [inline]
 __ia32_sys_socket+0x6f/0xb0 net/socket.c:1527
 do_syscall_32_irqs_on arch/x86/entry/common.c:84 [inline]
 __do_fast_syscall_32+0x57/0x80 arch/x86/entry/common.c:126
 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:149
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7fb3549
Code: Bad RIP value.
RSP: 002b:00000000f556b0cc EFLAGS: 00000296 ORIG_RAX: 0000000000000167
RAX: ffffffffffffffda RBX: 000000000000001d RCX: 0000000000000003
RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor.4:931 blocked for more than 144 seconds.
      Not tainted 5.9.0-rc1-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.4  state:D stack:29824 pid:  931 ppid:  7238 flags:0x20020004
Call Trace:
 context_switch kernel/sched/core.c:3778 [inline]
 __schedule+0x8e5/0x21e0 kernel/sched/core.c:4527
 schedule+0xd0/0x2a0 kernel/sched/core.c:4602
 rwsem_down_write_slowpath+0x603/0xc60 kernel/locking/rwsem.c:1235
 __down_write kernel/locking/rwsem.c:1389 [inline]
 down_write+0x137/0x150 kernel/locking/rwsem.c:1532
 register_netdevice_notifier+0x1e/0x260 net/core/dev.c:1814
 bcm_init+0x1a3/0x210 net/can/bcm.c:1451
 can_create+0x27c/0x4d0 net/can/af_can.c:168
 __sock_create+0x3ca/0x740 net/socket.c:1427
 sock_create net/socket.c:1478 [inline]
 __sys_socket+0xef/0x200 net/socket.c:1520
 __do_sys_socket net/socket.c:1529 [inline]
 __se_sys_socket net/socket.c:1527 [inline]
 __ia32_sys_socket+0x6f/0xb0 net/socket.c:1527
 do_syscall_32_irqs_on arch/x86/entry/common.c:84 [inline]
 __do_fast_syscall_32+0x57/0x80 arch/x86/entry/common.c:126
 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:149
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7fb3549
Code: Bad RIP value.
RSP: 002b:00000000f554a0cc EFLAGS: 00000296 ORIG_RAX: 0000000000000167
RAX: ffffffffffffffda RBX: 000000000000001d RCX: 0000000000000002
RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Showing all locks held in the system:
1 lock held by khungtaskd/1171:
 #0: ffffffff89bd6340 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5825
1 lock held by in:imklog/6509:
 #0: ffff88809e88caf0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:930
2 locks held by agetty/6507:
 #0: ffff8880945f4098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267
 #1: ffffc900011002e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x223/0x1a30 drivers/tty/n_tty.c:2156
2 locks held by agetty/6535:
 #0: ffff888093984098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267
 #1: ffffc900010d42e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x223/0x1a30 drivers/tty/n_tty.c:2156
3 locks held by kworker/u4:1/32426:
 #0: ffff8880a97b5138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff8880a97b5138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline]
 #0: ffff8880a97b5138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline]
 #0: ffff8880a97b5138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline]
 #0: ffff8880a97b5138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
 #0: ffff8880a97b5138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240
 #1: ffffc90007cdfda8 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244
 #2: ffffffff8a7d8bf0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa00 net/core/net_namespace.c:565
4 locks held by kworker/u4:11/32434:
1 lock held by syz-executor.5/661:
1 lock held by syz-executor.4/884:
 #0: ffffffff8a7d8bf0 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1e/0x260 net/core/dev.c:1814
1 lock held by syz-executor.4/909:
 #0: ffffffff8a7d8bf0 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1e/0x260 net/core/dev.c:1814
1 lock held by syz-executor.4/920:
 #0: ffffffff8a7d8bf0 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1e/0x260 net/core/dev.c:1814
1 lock held by syz-executor.4/931:
 #0: ffffffff8a7d8bf0 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1e/0x260 net/core/dev.c:1814

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

NMI backtrace for cpu 1
CPU: 1 PID: 1171 Comm: khungtaskd Not tainted 5.9.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x18f/0x20d lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1b3/0x223 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline]
 watchdog+0xd7d/0x1000 kernel/hung_task.c:295
 kthread+0x3b5/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 32430 Comm: kworker/u4:6 Not tainted 5.9.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_nc_worker
RIP: 0010:rcu_is_watching+0x80/0xb0 kernel/rcu/tree.c:1112
Code: c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 25 8b 83 e0 00 00 00 d1 e8 83 e0 01 65 ff 0d 20 f4 a0 7e <74> 06 48 83 c4 08 5b c3 e8 42 6c 9f ff 48 83 c4 08 5b c3 e8 48 4b
RSP: 0018:ffffc90008137c68 EFLAGS: 00000286
RAX: 0000000000000001 RBX: ffff8880ae636c00 RCX: 1ffffffff1308520
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8880ae636ce0
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8c5f09e7
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
R13: 0000000000000000 R14: dffffc0000000000 R15: 000000000000021e
FS:  0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c00038f000 CR3: 000000009301e000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 rcu_read_lock include/linux/rcupdate.h:635 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:407 [inline]
 batadv_nc_worker+0xa26/0xe50 net/batman-adv/network-coding.c:718
 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415
 kthread+0x3b5/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Crashes (2):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kasan-gce-386 2020/08/19 15:39 upstream 18445bf405cb 94b45706 .config log report
ci-upstream-kasan-gce-386 2020/08/15 01:56 upstream b923f1247b72 424dd8e7 .config log report
* Struck through repros no longer work on HEAD.