syzbot


INFO: task hung in cangw_pernet_exit_batch

Status: auto-obsoleted due to no activity on 2023/09/13 14:11
Reported-by: syzbot+fd1a54195f3f235ea8d3@syzkaller.appspotmail.com
First crash: 568d, last: 548d
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in cangw_pernet_exit_batch (2) can 16 502d 760d 0/28 auto-obsoleted due to no activity on 2023/10/19 02:51
upstream INFO: task hung in cangw_pernet_exit_batch (3) can 33 149d 164d 26/28 fixed on 2024/07/09 19:14
upstream INFO: task hung in cangw_pernet_exit_batch can 11 877d 890d 0/28 auto-obsoleted due to no activity on 2022/10/09 07:17
linux-6.1 INFO: task hung in cangw_pernet_exit_batch (2) 18 169d 196d 0/3 auto-obsoleted due to no activity on 2024/08/27 12:37

Sample crash report:
INFO: task kworker/u4:3:46 blocked for more than 145 seconds.
      Not tainted 6.1.32-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:3    state:D stack:20288 pid:46    ppid:2      flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x132c/0x4330 kernel/sched/core.c:6554
 schedule+0xbf/0x180 kernel/sched/core.c:6630
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6689
 __mutex_lock_common+0xe2b/0x2520 kernel/locking/mutex.c:679
 __mutex_lock kernel/locking/mutex.c:747 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:799
 cangw_pernet_exit_batch+0x1c/0x90 net/can/gw.c:1250
 ops_exit_list net/core/net_namespace.c:174 [inline]
 cleanup_net+0x763/0xb60 net/core/net_namespace.c:601
 process_one_work+0x8aa/0x11f0 kernel/workqueue.c:2289
 worker_thread+0xa5f/0x1210 kernel/workqueue.c:2436
 kthread+0x26e/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>
INFO: task syz-executor.0:11428 blocked for more than 145 seconds.
      Not tainted 6.1.32-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0  state:D stack:24504 pid:11428 ppid:3576   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x132c/0x4330 kernel/sched/core.c:6554
 schedule+0xbf/0x180 kernel/sched/core.c:6630
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6689
 __mutex_lock_common+0xe2b/0x2520 kernel/locking/mutex.c:679
 __mutex_lock kernel/locking/mutex.c:747 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:799
 ip_tunnel_init_net+0x20f/0x700 net/ipv4/ip_tunnel.c:1072
 ops_init+0x356/0x600 net/core/net_namespace.c:135
 setup_net+0x4b5/0xb90 net/core/net_namespace.c:332
 copy_net_ns+0x395/0x5d0 net/core/net_namespace.c:478
 create_new_namespaces+0x425/0x7a0 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x11e/0x170 kernel/nsproxy.c:226
 ksys_unshare+0x580/0xb20 kernel/fork.c:3196
 __do_sys_unshare kernel/fork.c:3267 [inline]
 __se_sys_unshare kernel/fork.c:3265 [inline]
 __x64_sys_unshare+0x34/0x40 kernel/fork.c:3265
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f36cb08c169
RSP: 002b:00007f36cbd84168 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f36cb1abf80 RCX: 00007f36cb08c169
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007f36cb0e7ca1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffdcc17242f R14: 00007f36cbd84300 R15: 0000000000022000
 </TASK>
INFO: task syz-executor.3:11446 blocked for more than 145 seconds.
      Not tainted 6.1.32-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3  state:D stack:27256 pid:11446 ppid:3588   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x132c/0x4330 kernel/sched/core.c:6554
 schedule+0xbf/0x180 kernel/sched/core.c:6630
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6689
 __mutex_lock_common+0xe2b/0x2520 kernel/locking/mutex.c:679
 __mutex_lock kernel/locking/mutex.c:747 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:799
 rtnl_lock net/core/rtnetlink.c:74 [inline]
 rtnetlink_rcv_msg+0x720/0xf00 net/core/rtnetlink.c:6088
 netlink_rcv_skb+0x1cd/0x410 net/netlink/af_netlink.c:2524
 netlink_unicast_kernel net/netlink/af_netlink.c:1328 [inline]
 netlink_unicast+0x7bf/0x990 net/netlink/af_netlink.c:1354
 netlink_sendmsg+0xa26/0xd60 net/netlink/af_netlink.c:1902
 sock_sendmsg_nosec net/socket.c:716 [inline]
 sock_sendmsg net/socket.c:736 [inline]
 ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2482
 ___sys_sendmsg net/socket.c:2536 [inline]
 __sys_sendmsg+0x2a9/0x390 net/socket.c:2565
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f4e6b88c169
RSP: 002b:00007f4e6c4fd168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f4e6b9ac050 RCX: 00007f4e6b88c169
RDX: 0000000000000000 RSI: 0000000020000240 RDI: 0000000000000006
RBP: 00007f4e6b8e7ca1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc98b21e3f R14: 00007f4e6c4fd300 R15: 0000000000022000
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8cf27470 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xd20 kernel/rcu/tasks.h:510
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8cf27c70 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xd20 kernel/rcu/tasks.h:510
1 lock held by khungtaskd/28:
 #0: ffffffff8cf272a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
4 locks held by kworker/u4:3/46:
 #0: ffff888012606938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x77a/0x11f0
 #1: ffffc90000b77d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7bd/0x11f0 kernel/workqueue.c:2264
 #2: ffffffff8e087850 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:563
 #3: ffffffff8e093c08 (rtnl_mutex){+.+.}-{3:3}, at: cangw_pernet_exit_batch+0x1c/0x90 net/can/gw.c:1250
3 locks held by kworker/0:2/150:
 #0: ffff888027cc3538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x77a/0x11f0
 #1: ffffc90002dcfd20 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7bd/0x11f0 kernel/workqueue.c:2264
 #2: ffffffff8e093c08 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0x15/0x30 net/ipv6/addrconf.c:4629
2 locks held by getty/3306:
 #0: ffff8880284b3098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2177
2 locks held by kworker/u4:12/3763:
3 locks held by kworker/1:14/9429:
 #0: ffff888027cc3538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x77a/0x11f0
 #1: ffffc900152d7d20 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7bd/0x11f0 kernel/workqueue.c:2264
 #2: ffffffff8e093c08 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0x15/0x30 net/ipv6/addrconf.c:4629
2 locks held by syz-executor.0/11428:
 #0: ffffffff8e087850 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x37b/0x5d0 net/core/net_namespace.c:474
 #1: ffffffff8e093c08 (rtnl_mutex){+.+.}-{3:3}, at: ip_tunnel_init_net+0x20f/0x700 net/ipv4/ip_tunnel.c:1072
3 locks held by syz-executor.1/11426:
1 lock held by syz-executor.3/11446:
 #0: ffffffff8e093c08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8e093c08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x720/0xf00 net/core/rtnetlink.c:6088
1 lock held by syz-executor.1/11523:
 #0: ffffffff8e093c08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8e093c08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x720/0xf00 net/core/rtnetlink.c:6088
1 lock held by syz-executor.3/11529:
 #0: ffffffff8e093c08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8e093c08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x720/0xf00 net/core/rtnetlink.c:6088
1 lock held by syz-executor.0/11530:
 #0: ffffffff8e093c08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8e093c08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x720/0xf00 net/core/rtnetlink.c:6088
1 lock held by syz-executor.1/11542:
 #0: ffffffff8e093c08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8e093c08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x720/0xf00 net/core/rtnetlink.c:6088
1 lock held by syz-executor.3/11546:
 #0: ffffffff8e093c08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8e093c08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x720/0xf00 net/core/rtnetlink.c:6088
1 lock held by syz-executor.0/11549:
 #0: ffffffff8e093c08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8e093c08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x720/0xf00 net/core/rtnetlink.c:6088

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

NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.32-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1b0/0x3f0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
 watchdog+0xf18/0xf60 kernel/hung_task.c:377
 kthread+0x26e/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 2982 Comm: syslogd Not tainted 6.1.32-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
RIP: 0010:preempt_count_sub+0x3/0x160 kernel/sched/core.c:5726
Code: c1 a8 4d 53 8e 80 e1 07 80 c1 03 38 c1 7c 80 48 c7 c7 a8 4d 53 8e e8 0c 29 82 00 e9 6f ff ff ff 0f 1f 80 00 00 00 00 41 56 53 <89> fb 48 c7 c0 60 11 a8 91 48 c1 e8 03 49 be 00 00 00 00 00 fc ff
RSP: 0018:ffffc9000c1a7b88 EFLAGS: 00000246
RAX: 1ffff1100e9b975f RBX: ffff888074dcbaf8 RCX: ffffffff81695e63
RDX: 0000000000000001 RSI: 0000000000000008 RDI: 0000000000000001
RBP: ffffc9000c1a7c60 R08: dffffc0000000000 R09: ffffed100e9b9760
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffc9000c1a7be0
R13: 1ffff92001834f78 R14: ffff8880283e1dc0 R15: dffffc0000000000
FS:  00007f5d378c9380(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c006719000 CR3: 00000000296d5000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 rwsem_write_trylock+0x166/0x210 kernel/locking/rwsem.c:267
 __down_write_common kernel/locking/rwsem.c:1313 [inline]
 __down_write kernel/locking/rwsem.c:1323 [inline]
 down_write+0x42/0x60 kernel/locking/rwsem.c:1574
 inode_lock include/linux/fs.h:756 [inline]
 generic_file_write_iter+0x7f/0x310 mm/filemap.c:3911
 call_write_iter include/linux/fs.h:2205 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x7ae/0xba0 fs/read_write.c:584
 ksys_write+0x19c/0x2c0 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f5d37a1dbf2
Code: 89 c7 48 89 44 24 08 e8 7b 34 fa ff 48 8b 44 24 08 48 83 c4 28 c3 c3 64 8b 04 25 18 00 00 00 85 c0 75 20 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 6f 48 8b 15 07 a2 0d 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffe70a44638 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f5d37a1dbf2
RDX: 000000000000005e RSI: 000055a544e53c50 RDI: 0000000000000003
RBP: 000055a544e53c50 R08: 0000000000000001 R09: 0000000000000000
R10: 00007f5d37bbc3a3 R11: 0000000000000246 R12: 000000000000005e
R13: 00007f5d378c9300 R14: 0000000000000004 R15: 000055a544e53a60
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/06/05 14:11 linux-6.1.y 76ba310227d2 a4ae4f42 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in cangw_pernet_exit_batch
2023/05/16 19:49 linux-6.1.y bf4ad6fa4e53 11c89444 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in cangw_pernet_exit_batch
* Struck through repros no longer work on HEAD.