syzbot


INFO: task hung in cangw_pernet_exit

Status: auto-closed as invalid on 2020/11/15 21:42
Reported-by: syzbot+2d764bc1be1ff9305cef@syzkaller.appspotmail.com
First crash: 932d, last: 932d
similar bugs (4):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in cangw_pernet_exit 14 1276d 1774d 0/24 closed as invalid on 2019/10/23 07:27
linux-4.19 INFO: task hung in cangw_pernet_exit (2) 6 203d 439d 0/1 auto-obsoleted due to no activity on 2022/11/15 03:06
upstream INFO: task hung in cangw_pernet_exit (2) 85 680d 856d 0/24 auto-closed as invalid on 2021/06/26 13:07
upstream INFO: task hung in cangw_pernet_exit (3) syz unreliable 290 405d 512d 0/24 closed as invalid on 2022/02/08 10:22

Sample crash report:
device bridge0 left promiscuous mode
bridge3: port 1(bridge_slave_0) entered disabled state
batman_adv: batadv0: Interface deactivated: batadv_slave_0
batman_adv: batadv0: Interface deactivated: batadv_slave_1
INFO: task kworker/u4:1:23 blocked for more than 140 seconds.
      Not tainted 4.19.133-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u4:1    D25432    23      2 0x80000000
Workqueue: netns cleanup_net
Call Trace:
 context_switch kernel/sched/core.c:2826 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3515
 schedule+0x8d/0x1b0 kernel/sched/core.c:3559
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3617
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x647/0x1260 kernel/locking/mutex.c:1072
 cangw_pernet_exit+0xe/0x20 net/can/gw.c:1029
 ops_exit_list+0xa5/0x150 net/core/net_namespace.c:153
 cleanup_net+0x3b4/0x8b0 net/core/net_namespace.c:553
 process_one_work+0x864/0x1570 kernel/workqueue.c:2155
 worker_thread+0x64c/0x1130 kernel/workqueue.c:2298
 kthread+0x30b/0x410 kernel/kthread.c:246
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
INFO: task syz-executor.3:21913 blocked for more than 140 seconds.
      Not tainted 4.19.133-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3  D29072 21913   6776 0x80000004
Call Trace:
 context_switch kernel/sched/core.c:2826 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3515
 schedule+0x8d/0x1b0 kernel/sched/core.c:3559
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3617
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x647/0x1260 kernel/locking/mutex.c:1072
 gtp_net_exit+0x1ba/0x37d drivers/net/gtp.c:1360
 ops_exit_list+0xa5/0x150 net/core/net_namespace.c:153
 setup_net+0x3d1/0x720 net/core/net_namespace.c:332
 copy_net_ns+0x1f7/0x335 net/core/net_namespace.c:438
 create_new_namespaces+0x3f6/0x7b0 kernel/nsproxy.c:107
 unshare_nsproxy_namespaces+0xbd/0x1f0 kernel/nsproxy.c:206
 ksys_unshare+0x36c/0x9a0 kernel/fork.c:2530
 __do_sys_unshare kernel/fork.c:2598 [inline]
 __se_sys_unshare kernel/fork.c:2596 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:2596
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c1d9
Code: 18 0f 57 c0 0f 11 44 24 20 48 c7 44 24 30 64 00 00 00 0f 11 44 24 38 48 89 5c 24 48 e8 c0 dc ff ff 48 8b 44 24 50 48 85 c0 75 <12> 48 8b 8c 24 c8 01 00 00 0f ba e1 00 0f 83 13 01 00 00 48 83 f8
RSP: 002b:00007fb28b2b4c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 0000000000034280 RCX: 000000000045c1d9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 000000000078bf30 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bf0c
R13: 00007fff7693420f R14: 00007fb28b2b59c0 R15: 000000000078bf0c
INFO: task syz-executor.3:21917 blocked for more than 140 seconds.
      Not tainted 4.19.133-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3  D27376 21917   6776 0x80000004
Call Trace:
 context_switch kernel/sched/core.c:2826 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3515
 schedule+0x8d/0x1b0 kernel/sched/core.c:3559
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3617
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x647/0x1260 kernel/locking/mutex.c:1072
 gtp_net_exit+0x1ba/0x37d drivers/net/gtp.c:1360
 ops_exit_list+0xa5/0x150 net/core/net_namespace.c:153
 setup_net+0x3d1/0x720 net/core/net_namespace.c:332
 copy_net_ns+0x1f7/0x335 net/core/net_namespace.c:438
 create_new_namespaces+0x3f6/0x7b0 kernel/nsproxy.c:107
 unshare_nsproxy_namespaces+0xbd/0x1f0 kernel/nsproxy.c:206
 ksys_unshare+0x36c/0x9a0 kernel/fork.c:2530
 __do_sys_unshare kernel/fork.c:2598 [inline]
 __se_sys_unshare kernel/fork.c:2596 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:2596
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c1d9
Code: 18 0f 57 c0 0f 11 44 24 20 48 c7 44 24 30 64 00 00 00 0f 11 44 24 38 48 89 5c 24 48 e8 c0 dc ff ff 48 8b 44 24 50 48 85 c0 75 <12> 48 8b 8c 24 c8 01 00 00 0f ba e1 00 0f 83 13 01 00 00 48 83 f8
RSP: 002b:00007fb28b293c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 0000000000034280 RCX: 000000000045c1d9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 000000000078bfd0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bfac
R13: 00007fff7693420f R14: 00007fb28b2949c0 R15: 000000000078bfac

Showing all locks held in the system:
3 locks held by kworker/0:0/5:
 #0: 00000000d481f186 ((wq_completion)"events"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2126
 #1: 00000000f2fd61e0 ((linkwatch_work).work){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2130
 #2: 00000000570b22c4 (rtnl_mutex){+.+.}, at: linkwatch_event+0xb/0x60 net/core/link_watch.c:236
3 locks held by kworker/0:1/14:
 #0: 0000000046f4c087 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2126
 #1: 000000004d041672 ((addr_chk_work).work){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2130
 #2: 00000000570b22c4 (rtnl_mutex){+.+.}, at: addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4475
3 locks held by kworker/1:0/19:
 #0: 00000000d481f186 ((wq_completion)"events"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2126
 #1: 00000000893dfd77 (deferred_process_work){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2130
 #2: 00000000570b22c4 (rtnl_mutex){+.+.}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:150
4 locks held by kworker/u4:1/23:
 #0: 00000000ce689af0 ((wq_completion)"%s""netns"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2126
 #1: 0000000022a498f4 (net_cleanup_work){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2130
 #2: 00000000b50d6492 (pernet_ops_rwsem){++++}, at: cleanup_net+0xa8/0x8b0 net/core/net_namespace.c:520
 #3: 00000000570b22c4 (rtnl_mutex){+.+.}, at: cangw_pernet_exit+0xe/0x20 net/can/gw.c:1029
1 lock held by khungtaskd/1083:
 #0: 00000000747b8b8a (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4440
1 lock held by in:imklog/6142:
 #0: 00000000c018018d (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767
1 lock held by syz-executor.2/21891:
2 locks held by syz-executor.3/21913:
 #0: 00000000b50d6492 (pernet_ops_rwsem){++++}, at: copy_net_ns+0x1d8/0x335 net/core/net_namespace.c:434
 #1: 00000000570b22c4 (rtnl_mutex){+.+.}, at: gtp_net_exit+0x1ba/0x37d drivers/net/gtp.c:1360
2 locks held by syz-executor.3/21917:
 #0: 00000000b50d6492 (pernet_ops_rwsem){++++}, at: copy_net_ns+0x1d8/0x335 net/core/net_namespace.c:434
 #1: 00000000570b22c4 (rtnl_mutex){+.+.}, at: gtp_net_exit+0x1ba/0x37d drivers/net/gtp.c:1360

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

NMI backtrace for cpu 0
CPU: 0 PID: 1083 Comm: khungtaskd Not tainted 4.19.133-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+0x1fc/0x2fe lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1a6/0x1eb lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline]
 watchdog+0x991/0xe60 kernel/hung_task.c:287
 kthread+0x30b/0x410 kernel/kthread.c:246
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 21891 Comm: syz-executor.2 Not tainted 4.19.133-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__hrtimer_get_next_event kernel/time/hrtimer.c:563 [inline]
RIP: 0010:hrtimer_interrupt+0x390/0x930 kernel/time/hrtimer.c:1524
Code: 00 00 00 00 0f 85 82 00 00 00 e8 eb 50 0e 00 48 8b 74 24 38 48 89 f0 48 c1 e8 03 0f b6 14 18 48 89 f0 83 e0 07 83 c0 03 38 d0 <7c> 08 84 d2 0f 85 bd 03 00 00 41 8b 57 3c 49 8d 6f 70 48 89 e8 48
RSP: 0018:ffff8880ae707f08 EFLAGS: 00000002
RAX: 0000000000000007 RBX: dffffc0000000000 RCX: 7fffffffffffffff
RDX: 0000000000000000 RSI: ffff8880ae725bfc RDI: 0000000000000001
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: ffffffff8ad2405b R12: 0000000000000082
R13: ffff8880ae725c04 R14: 0000000000000000 R15: ffff8880ae725bc0
FS:  00007f4c5ee6a700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7d84cea1b0 CR3: 000000009ac1a000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1067 [inline]
 smp_apic_timer_interrupt+0x10c/0x550 arch/x86/kernel/apic/apic.c:1092
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894
 </IRQ>
RIP: 0010:___might_sleep+0x20/0x2b0 kernel/sched/core.c:6159
Code: e9 5f ff ff ff 0f 1f 44 00 00 41 56 41 55 41 54 41 89 f4 55 48 89 fd 53 89 d3 e8 cb cf 0f 00 85 c0 74 0d 80 3d 1b 85 5f 08 00 <0f> 84 b3 01 00 00 e8 b5 cf 0f 00 85 c0 74 0d 80 3d 04 85 5f 08 00
RSP: 0018:ffff888215af6920 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffff888212d08b84
RBP: ffffffff882eb060 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000789
R13: 000000000000519c R14: 0000000000000000 R15: 0000000000000001
 get_next_corpse net/netfilter/nf_conntrack_core.c:1929 [inline]
 nf_ct_iterate_cleanup+0x24c/0x520 net/netfilter/nf_conntrack_core.c:1951
 nf_ct_iterate_cleanup_net net/netfilter/nf_conntrack_core.c:2036 [inline]
 nf_ct_iterate_cleanup_net+0x113/0x170 net/netfilter/nf_conntrack_core.c:2021
 masq_device_event+0xae/0xe0 net/ipv6/netfilter/nf_nat_masquerade_ipv6.c:77
 notifier_call_chain+0xc0/0x230 kernel/notifier.c:93
 call_netdevice_notifiers net/core/dev.c:1762 [inline]
 dev_close_many+0x323/0x670 net/core/dev.c:1514
 vlan_device_event+0x8cd/0x1e40 net/8021q/vlan.c:444
 notifier_call_chain+0xc0/0x230 kernel/notifier.c:93
 call_netdevice_notifiers net/core/dev.c:1762 [inline]
 __dev_notify_flags+0x1da/0x2b0 net/core/dev.c:7710
 dev_change_flags+0xf0/0x140 net/core/dev.c:7744
 do_setlink+0x14f1/0x3540 net/core/rtnetlink.c:2449
 rtnl_group_changelink net/core/rtnetlink.c:2925 [inline]
 rtnl_newlink+0xbc0/0x15a0 net/core/rtnetlink.c:3083
 rtnetlink_rcv_msg+0x453/0xb80 net/core/rtnetlink.c:4777
 netlink_rcv_skb+0x160/0x440 net/netlink/af_netlink.c:2455
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x4d5/0x690 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x6bb/0xc40 net/netlink/af_netlink.c:1909
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xc3/0x120 net/socket.c:632
 ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2115
 __sys_sendmsg net/socket.c:2153 [inline]
 __do_sys_sendmsg net/socket.c:2162 [inline]
 __se_sys_sendmsg net/socket.c:2160 [inline]
 __x64_sys_sendmsg+0x132/0x220 net/socket.c:2160
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c1d9
Code: 8d b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 5b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f4c5ee69c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 000000000002af00 RCX: 000000000045c1d9
RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000006
RBP: 000000000078bf40 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bf0c
R13: 00007ffc30697c8f R14: 00007f4c5ee6a9c0 R15: 000000000078bf0c

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets Title
ci2-linux-4-19 2020/07/18 21:41 linux-4.19.y 17a87580a885 9c812472 .config console log report
* Struck through repros no longer work on HEAD.