syzbot


INFO: task hung in netlink_dump (2)

Status: auto-closed as invalid on 2022/05/26 21:32
Subsystems: net
[Documentation on labels]
First crash: 762d, last: 761d
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in netlink_dump net 1 932d 932d 0/26 auto-closed as invalid on 2021/12/07 11:04
linux-6.1 INFO: task hung in netlink_dump 3 27d 46d 0/3 upstream: reported on 2024/02/11 17:56
upstream INFO: task hung in netlink_dump (3) net 78 45d 203d 0/26 closed as invalid on 2024/02/12 15:10
upstream INFO: task hung in netlink_dump (4) net 71 16d 29d 24/26 internal: reported on 2024/02/28 07:35

Sample crash report:
INFO: task dhcpcd:3174 blocked for more than 143 seconds.
      Not tainted 5.17.0-rc5-syzkaller-00041-g73878e5eb1bd #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:dhcpcd          state:D stack:22840 pid: 3174 ppid:  3173 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4995 [inline]
 __schedule+0xa94/0x4910 kernel/sched/core.c:6304
 schedule+0xd2/0x260 kernel/sched/core.c:6377
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6436
 __mutex_lock_common kernel/locking/mutex.c:673 [inline]
 __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:733
 netlink_dump+0xb0/0xb70 net/netlink/af_netlink.c:2223
 netlink_recvmsg+0xa6f/0xea0 net/netlink/af_netlink.c:2002
 sock_recvmsg_nosec net/socket.c:948 [inline]
 sock_recvmsg net/socket.c:966 [inline]
 sock_recvmsg net/socket.c:962 [inline]
 ____sys_recvmsg+0x2c4/0x600 net/socket.c:2632
 ___sys_recvmsg+0x127/0x200 net/socket.c:2674
 __sys_recvmsg+0xe2/0x1a0 net/socket.c:2704
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f7a41fe1003
RSP: 002b:00007fff3f28daa8 EFLAGS: 00000246 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 00007fff3f28ebe0 RCX: 00007f7a41fe1003
RDX: 0000000000000000 RSI: 00007fff3f28eb00 RDI: 000000000000001b
RBP: 00007fff3f28eb70 R08: 0000000000000000 R09: 00007f7a420a1a60
R10: 0000000000000062 R11: 0000000000000246 R12: 00007fff3f28eb00
R13: 00007fff3f28eae4 R14: 00007fff3f28eaf0 R15: 0000000000000dd0
 </TASK>
INFO: task kworker/0:13:10655 blocked for more than 143 seconds.
      Not tainted 5.17.0-rc5-syzkaller-00041-g73878e5eb1bd #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:13    state:D stack:23000 pid:10655 ppid:     2 flags:0x00004000
Workqueue: events linkwatch_event
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4995 [inline]
 __schedule+0xa94/0x4910 kernel/sched/core.c:6304
 schedule+0xd2/0x260 kernel/sched/core.c:6377
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6436
 __mutex_lock_common kernel/locking/mutex.c:673 [inline]
 __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:733
 linkwatch_event+0xb/0x60 net/core/link_watch.c:262
 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307
 worker_thread+0x657/0x1110 kernel/workqueue.c:2454
 kthread+0x2e9/0x3a0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
INFO: task kworker/0:6:2334 blocked for more than 143 seconds.
      Not tainted 5.17.0-rc5-syzkaller-00041-g73878e5eb1bd #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:6     state:D stack:26584 pid: 2334 ppid:     2 flags:0x00004000
Workqueue: events switchdev_deferred_process_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4995 [inline]
 __schedule+0xa94/0x4910 kernel/sched/core.c:6304
 schedule+0xd2/0x260 kernel/sched/core.c:6377
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6436
 __mutex_lock_common kernel/locking/mutex.c:673 [inline]
 __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:733
 switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:75
 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307
 worker_thread+0x657/0x1110 kernel/workqueue.c:2454
 kthread+0x2e9/0x3a0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
INFO: task syz-executor.5:10920 blocked for more than 144 seconds.
      Not tainted 5.17.0-rc5-syzkaller-00041-g73878e5eb1bd #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.5  state:D stack:24056 pid:10920 ppid:     1 flags:0x20000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4995 [inline]
 __schedule+0xa94/0x4910 kernel/sched/core.c:6304
 schedule+0xd2/0x260 kernel/sched/core.c:6377
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6436
 __mutex_lock_common kernel/locking/mutex.c:673 [inline]
 __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:733
 rtnl_lock net/core/rtnetlink.c:72 [inline]
 rtnetlink_rcv_msg+0x3be/0xb80 net/core/rtnetlink.c:5593
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x539/0x7e0 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x904/0xe00 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:725
 __sys_sendto+0x21c/0x320 net/socket.c:2040
 __do_compat_sys_socketcall+0x47f/0x660 net/compat.c:476
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf6eec549
RSP: 002b:00000000f757d910 EFLAGS: 00000286 ORIG_RAX: 0000000000000066
RAX: ffffffffffffffda RBX: 000000000000000b RCX: 00000000f757d924
RDX: 0000000000000000 RSI: 00000000f7024000 RDI: 00000000f7f82288
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
INFO: task syz-executor.1:10921 blocked for more than 144 seconds.
      Not tainted 5.17.0-rc5-syzkaller-00041-g73878e5eb1bd #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.1  state:D stack:24056 pid:10921 ppid:     1 flags:0x20000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4995 [inline]
 __schedule+0xa94/0x4910 kernel/sched/core.c:6304
 schedule+0xd2/0x260 kernel/sched/core.c:6377
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6436
 __mutex_lock_common kernel/locking/mutex.c:673 [inline]
 __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:733
 rtnl_lock net/core/rtnetlink.c:72 [inline]
 rtnetlink_rcv_msg+0x3be/0xb80 net/core/rtnetlink.c:5593
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x539/0x7e0 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x904/0xe00 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:725
 __sys_sendto+0x21c/0x320 net/socket.c:2040
 __do_compat_sys_socketcall+0x47f/0x660 net/compat.c:476
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf6f3d549
RSP: 002b:00000000f75ce910 EFLAGS: 00000286 ORIG_RAX: 0000000000000066
RAX: ffffffffffffffda RBX: 000000000000000b RCX: 00000000f75ce924
RDX: 0000000000000000 RSI: 00000000f7075000 RDI: 00000000f7fd3288
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8bb845e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6460
1 lock held by dhcpcd/3174:
 #0: ffffffff8d330428 (rtnl_mutex){+.+.}-{3:3}, at: netlink_dump+0xb0/0xb70 net/netlink/af_netlink.c:2223
2 locks held by getty/3278:
 #0: ffff88814b022098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:244
 #1: ffffc90002b662e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2075
4 locks held by kworker/u4:6/10317:
 #0: ffff888140053138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888140053138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888140053138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline]
 #0: ffff888140053138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:631 [inline]
 #0: ffff888140053138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:658 [inline]
 #0: ffff888140053138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x890/0x1650 kernel/workqueue.c:2278
 #1: ffffc9000f8a7db8 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x8c4/0x1650 kernel/workqueue.c:2282
 #2: ffffffff8d31b910 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xb00 net/core/net_namespace.c:559
 #3: ffffffff8d330428 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock_unregistering net/core/dev.c:10898 [inline]
 #3: ffffffff8d330428 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0xe8/0x3c0 net/core/dev.c:10936
3 locks held by kworker/0:11/10653:
 #0: ffff888022e9a138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888022e9a138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888022e9a138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline]
 #0: ffff888022e9a138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:631 [inline]
 #0: ffff888022e9a138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:658 [inline]
 #0: ffff888022e9a138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x890/0x1650 kernel/workqueue.c:2278
 #1: ffffc9001130fdb8 ((addr_chk_work).work){+.+.}-{0:0}, at: process_one_work+0x8c4/0x1650 kernel/workqueue.c:2282
 #2: ffffffff8d330428 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4608
3 locks held by kworker/0:13/10655:
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:631 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:658 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x890/0x1650 kernel/workqueue.c:2278
 #1: ffffc90011897db8 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x8c4/0x1650 kernel/workqueue.c:2282
 #2: ffffffff8d330428 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xb/0x60 net/core/link_watch.c:262
3 locks held by kworker/0:6/2334:
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:631 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:658 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x890/0x1650 kernel/workqueue.c:2278
 #1: ffffc9000a3cfdb8 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x8c4/0x1650 kernel/workqueue.c:2282
 #2: ffffffff8d330428 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:75
1 lock held by syz-executor.5/10920:
 #0: ffffffff8d330428 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d330428 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3be/0xb80 net/core/rtnetlink.c:5593
1 lock held by syz-executor.1/10921:
 #0: ffffffff8d330428 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d330428 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3be/0xb80 net/core/rtnetlink.c:5593

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

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.17.0-rc5-syzkaller-00041-g73878e5eb1bd #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1e6/0x230 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
 watchdog+0xc1d/0xf50 kernel/hung_task.c:369
 kthread+0x2e9/0x3a0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 10449 Comm: kworker/u4:11 Not tainted 5.17.0-rc5-syzkaller-00041-g73878e5eb1bd #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_nc_worker
RIP: 0010:iterate_chain_key kernel/locking/lockdep.c:419 [inline]
RIP: 0010:__lock_acquire+0xc3f/0x56c0 kernel/locking/lockdep.c:5015
Code: 5c 24 60 c1 e0 0d 66 0b 44 24 08 89 de 98 2b 44 24 58 33 44 24 50 89 c2 29 c1 01 d8 c1 c2 06 31 ca 89 d1 29 d6 01 c2 c1 c1 08 <31> f1 89 ce 29 c8 c1 c6 10 31 f0 8d 34 11 89 c1 29 c2 c1 c9 0d 01
RSP: 0018:ffffc9000f96fa40 EFLAGS: 00000006
RAX: 000000006812fdc1 RBX: 00000000970e346d RCX: 00000000ee5cae98
RDX: 0000000001015a6f RSI: 00000000fe1fd7bf RDI: ffffffff8ffc4c60
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8ffc2947
R10: fffffbfff1ff8528 R11: 0000000000000001 R12: ffff88809ffa61b0
R13: ffff88809ffa5700 R14: ffffffff8d9444e8 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c00aee88b0 CR3: 000000007f615000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 lock_acquire kernel/locking/lockdep.c:5639 [inline]
 lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5604
 rcu_lock_acquire include/linux/rcupdate.h:268 [inline]
 rcu_read_lock include/linux/rcupdate.h:694 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
 batadv_nc_worker+0x12d/0xfa0 net/batman-adv/network-coding.c:719
 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307
 worker_thread+0x657/0x1110 kernel/workqueue.c:2454
 kthread+0x2e9/0x3a0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
----------------
Code disassembly (best guess):
   0:	5c                   	pop    %rsp
   1:	24 60                	and    $0x60,%al
   3:	c1 e0 0d             	shl    $0xd,%eax
   6:	66 0b 44 24 08       	or     0x8(%rsp),%ax
   b:	89 de                	mov    %ebx,%esi
   d:	98                   	cwtl
   e:	2b 44 24 58          	sub    0x58(%rsp),%eax
  12:	33 44 24 50          	xor    0x50(%rsp),%eax
  16:	89 c2                	mov    %eax,%edx
  18:	29 c1                	sub    %eax,%ecx
  1a:	01 d8                	add    %ebx,%eax
  1c:	c1 c2 06             	rol    $0x6,%edx
  1f:	31 ca                	xor    %ecx,%edx
  21:	89 d1                	mov    %edx,%ecx
  23:	29 d6                	sub    %edx,%esi
  25:	01 c2                	add    %eax,%edx
  27:	c1 c1 08             	rol    $0x8,%ecx
* 2a:	31 f1                	xor    %esi,%ecx <-- trapping instruction
  2c:	89 ce                	mov    %ecx,%esi
  2e:	29 c8                	sub    %ecx,%eax
  30:	c1 c6 10             	rol    $0x10,%esi
  33:	31 f0                	xor    %esi,%eax
  35:	8d 34 11             	lea    (%rcx,%rdx,1),%esi
  38:	89 c1                	mov    %eax,%ecx
  3a:	29 c2                	sub    %eax,%edx
  3c:	c1 c9 0d             	ror    $0xd,%ecx
  3f:	01                   	.byte 0x1

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/02/25 12:01 upstream 73878e5eb1bd 7c337266 .config console log report info ci-upstream-kasan-gce-386 INFO: task hung in netlink_dump
2022/02/25 21:25 net-next-old 5ebaaa69bd27 45a13a73 .config console log report info ci-upstream-net-kasan-gce INFO: task hung in netlink_dump
* Struck through repros no longer work on HEAD.