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INFO: task hung in linkwatch_event

Status: auto-closed as invalid on 2020/02/07 01:11
Reported-by: syzbot+a028160ba279156cf97b@syzkaller.appspotmail.com
First crash: 2000d, last: 1886d
▶ ▼ Similar bugs (15)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-414 INFO: task hung in linkwatch_event C 7 1849d 2068d 0/1 public: reported C repro on 2019/04/10 16:14
linux-4.14 INFO: task hung in linkwatch_event (2) 1 870d 870d 0/1 auto-obsoleted due to no activity on 2022/11/19 11:58
android-44 INFO: task hung in linkwatch_event 6 2285d 2430d 0/2 auto-closed as invalid on 2019/03/05 13:11
linux-5.15 INFO: task hung in linkwatch_event 84 36d 332d 0/3 upstream: reported on 2024/01/11 11:32
upstream INFO: task hung in linkwatch_event (4) net C done 2394 6h22m 134d 0/28 upstream: reported C repro on 2024/07/27 06:21
upstream INFO: task hung in linkwatch_event net C 82 1877d 2489d 0/28 closed as dup on 2018/02/14 15:33
linux-4.14 INFO: task hung in linkwatch_event 5 1553d 1680d 0/1 auto-closed as invalid on 2021/01/05 01:42
linux-4.19 INFO: task hung in linkwatch_event (2) C error 217 644d 1732d 0/1 upstream: reported C repro on 2020/03/11 20:12
upstream INFO: task hung in linkwatch_event (2) net C done done 1033 958d 1684d 20/28 fixed on 2022/05/13 11:13
upstream INFO: task hung in linkwatch_event (3) net 1634 152d 746d 26/28 fixed on 2024/07/09 19:14
linux-4.14 INFO: task hung in linkwatch_event (3) 2 704d 705d 0/1 upstream: reported on 2023/01/03 10:49
android-49 INFO: task hung in linkwatch_event 13 2048d 2065d 0/3 auto-closed as invalid on 2019/10/25 08:50
linux-6.1 INFO: task hung in linkwatch_event (2) 32 87d 201d 0/3 auto-obsoleted due to no activity on 2024/11/21 00:32
linux-6.1 INFO: task hung in linkwatch_event 2 490d 606d 0/3 auto-obsoleted due to no activity on 2023/11/14 00:59
linux-6.1 INFO: task hung in linkwatch_event (3) 1 12d 12d 0/3 upstream: reported on 2024/11/25 15:51

Sample crash report:
net_ratelimit: 2 callbacks suppressed
protocol 88fb is buggy, dev hsr_slave_0
protocol 88fb is buggy, dev hsr_slave_1
protocol 88fb is buggy, dev hsr_slave_0
protocol 88fb is buggy, dev hsr_slave_1
INFO: task kworker/0:2:3225 blocked for more than 140 seconds.
      Not tainted 4.19.78 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/0:2     D26368  3225      2 0x80000000
Workqueue: events linkwatch_event
Call Trace:
 context_switch kernel/sched/core.c:2826 [inline]
 __schedule+0x866/0x1dc0 kernel/sched/core.c:3515
 schedule+0x92/0x1c0 kernel/sched/core.c:3559
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3617
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1300 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77
 linkwatch_event+0xf/0x70 net/core/link_watch.c:236
 process_one_work+0x989/0x1750 kernel/workqueue.c:2153
protocol 88fb is buggy, dev hsr_slave_0
protocol 88fb is buggy, dev hsr_slave_1
 worker_thread+0x98/0xe40 kernel/workqueue.c:2296
 kthread+0x354/0x420 kernel/kthread.c:246
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
INFO: task syz-executor.2:2093 blocked for more than 140 seconds.
      Not tainted 4.19.78 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D24200  2093   7636 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2826 [inline]
 __schedule+0x866/0x1dc0 kernel/sched/core.c:3515
 schedule+0x92/0x1c0 kernel/sched/core.c:3559
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3617
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1300 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 rtnl_lock net/core/rtnetlink.c:77 [inline]
 rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:4744
 netlink_rcv_skb+0x17d/0x460 net/netlink/af_netlink.c:2454
 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:4765
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x537/0x720 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1908
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:632
 ___sys_sendmsg+0x803/0x920 net/socket.c:2115
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2153
 __do_sys_sendmsg net/socket.c:2162 [inline]
 __se_sys_sendmsg net/socket.c:2160 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2160
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459a59
Code: fd b7 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 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f02a634fc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459a59
RDX: 0000000000000000 RSI: 0000000020000240 RDI: 0000000000000006
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f02a63506d4
R13: 00000000004c7be8 R14: 00000000004dd980 R15: 00000000ffffffff
INFO: task syz-executor.2:2107 blocked for more than 140 seconds.
      Not tainted 4.19.78 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D27768  2107   7636 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2826 [inline]
 __schedule+0x866/0x1dc0 kernel/sched/core.c:3515
 schedule+0x92/0x1c0 kernel/sched/core.c:3559
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3617
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1300 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 rtnl_lock net/core/rtnetlink.c:77 [inline]
 rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:4744
 netlink_rcv_skb+0x17d/0x460 net/netlink/af_netlink.c:2454
 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:4765
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x537/0x720 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1908
protocol 88fb is buggy, dev hsr_slave_0
protocol 88fb is buggy, dev hsr_slave_1
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:632
 ___sys_sendmsg+0x803/0x920 net/socket.c:2115
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2153
 __do_sys_sendmsg net/socket.c:2162 [inline]
 __se_sys_sendmsg net/socket.c:2160 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2160
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459a59
Code: fd b7 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 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f02a630dc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459a59
RDX: 0500000000000000 RSI: 0000000020000240 RDI: 0000000000000003
RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f02a630e6d4
R13: 00000000004c7be8 R14: 00000000004dd980 R15: 00000000ffffffff
INFO: task syz-executor.4:2106 blocked for more than 140 seconds.
      Not tainted 4.19.78 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.4  D23960  2106   7641 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2826 [inline]
 __schedule+0x866/0x1dc0 kernel/sched/core.c:3515
 schedule+0x92/0x1c0 kernel/sched/core.c:3559
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3617
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1300 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77
 sock_do_ioctl+0x24e/0x2f0 net/socket.c:963
 sock_ioctl+0x325/0x610 net/socket.c:1074
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0xd5f/0x1380 fs/ioctl.c:688
 ksys_ioctl+0xab/0xd0 fs/ioctl.c:705
 __do_sys_ioctl fs/ioctl.c:712 [inline]
 __se_sys_ioctl fs/ioctl.c:710 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:710
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459a59
Code: fd b7 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 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f20fa007c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459a59
RDX: 0000000000400200 RSI: 0000000000008912 RDI: 0000000000000003
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f20fa0086d4
R13: 00000000004c3458 R14: 00000000004d7080 R15: 00000000ffffffff
INFO: task syz-executor.4:2114 blocked for more than 140 seconds.
      Not tainted 4.19.78 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.4  D28456  2114   7641 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2826 [inline]
 __schedule+0x866/0x1dc0 kernel/sched/core.c:3515
 schedule+0x92/0x1c0 kernel/sched/core.c:3559
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3617
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1300 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 rtnl_lock net/core/rtnetlink.c:77 [inline]
 rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:4744
 netlink_rcv_skb+0x17d/0x460 net/netlink/af_netlink.c:2454
 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:4765
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x537/0x720 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1908
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:632
 ___sys_sendmsg+0x803/0x920 net/socket.c:2115
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2153
protocol 88fb is buggy, dev hsr_slave_0
protocol 88fb is buggy, dev hsr_slave_1
 __do_sys_sendmsg net/socket.c:2162 [inline]
 __se_sys_sendmsg net/socket.c:2160 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2160
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459a59
Code: fd b7 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 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f20f9fe6c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459a59
RDX: 0000000000000000 RSI: 0000000020000240 RDI: 0000000000000005
RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f20f9fe76d4
R13: 00000000004c7be8 R14: 00000000004dd980 R15: 00000000ffffffff
INFO: task syz-executor.5:2339 blocked for more than 140 seconds.
      Not tainted 4.19.78 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.5  D28456  2339   7884 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2826 [inline]
 __schedule+0x866/0x1dc0 kernel/sched/core.c:3515
 schedule+0x92/0x1c0 kernel/sched/core.c:3559
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3617
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1300 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 rtnl_lock net/core/rtnetlink.c:77 [inline]
 rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:4744
 netlink_rcv_skb+0x17d/0x460 net/netlink/af_netlink.c:2454
 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:4765
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x537/0x720 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1908
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:632
 ___sys_sendmsg+0x803/0x920 net/socket.c:2115
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2153
 __do_sys_sendmsg net/socket.c:2162 [inline]
 __se_sys_sendmsg net/socket.c:2160 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2160
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459a59
Code: Bad RIP value.
RSP: 002b:00007f3c6df3ac78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459a59
RDX: 0000000000000000 RSI: 0000000020000040 RDI: 0000000000000003
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3c6df3b6d4
R13: 00000000004c7bd7 R14: 00000000004dd968 R15: 00000000ffffffff

Showing all locks held in the system:
3 locks held by kworker/0:1/14:
 #0: 00000000c64ec04e ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline]
 #0: 00000000c64ec04e ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: 00000000c64ec04e ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline]
 #0: 00000000c64ec04e ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline]
 #0: 00000000c64ec04e ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline]
 #0: 00000000c64ec04e ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0: 00000000c64ec04e ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: process_one_work+0x87e/0x1750 kernel/workqueue.c:2124
 #1: 00000000de1b62d0 ((addr_chk_work).work){+.+.}, at: process_one_work+0x8b4/0x1750 kernel/workqueue.c:2128
 #2: 00000000d4eb7075 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77
1 lock held by khungtaskd/1039:
 #0: 0000000064bd99e9 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4438
3 locks held by kworker/0:2/3225:
 #0: 000000001d40af51 ((wq_completion)"events"){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline]
 #0: 000000001d40af51 ((wq_completion)"events"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: 000000001d40af51 ((wq_completion)"events"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline]
 #0: 000000001d40af51 ((wq_completion)"events"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline]
 #0: 000000001d40af51 ((wq_completion)"events"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline]
 #0: 000000001d40af51 ((wq_completion)"events"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0: 000000001d40af51 ((wq_completion)"events"){+.+.}, at: process_one_work+0x87e/0x1750 kernel/workqueue.c:2124
 #1: 0000000008c37c94 ((linkwatch_work).work){+.+.}, at: process_one_work+0x8b4/0x1750 kernel/workqueue.c:2128
 #2: 00000000d4eb7075 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77
1 lock held by rsyslogd/7468:
 #0: 000000003b97e53f (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:767
2 locks held by getty/7590:
 #0: 000000008fcba462 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
 #1: 000000004287efe6 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154
2 locks held by getty/7591:
 #0: 00000000b8f1e5d9 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
 #1: 000000006181b289 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154
2 locks held by getty/7592:
 #0: 0000000060a53eb1 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
 #1: 0000000001a5f049 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154
2 locks held by getty/7593:
 #0: 0000000045469485 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
 #1: 00000000d6c28e37 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154
2 locks held by getty/7594:
 #0: 000000003c669e73 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
 #1: 00000000a65b569b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154
2 locks held by getty/7595:
 #0: 00000000f660aa14 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
 #1: 0000000067072fbe (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154
2 locks held by getty/7596:
 #0: 000000007e259692 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:362
 #1: 00000000a078ef13 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b30 drivers/tty/n_tty.c:2154
1 lock held by syz-executor.5/8545:
 #0: 00000000d4eb7075 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77
2 locks held by kworker/0:3/17647:
 #0: 00000000258d11f3 ((wq_completion)"rcu_gp"){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline]
 #0: 00000000258d11f3 ((wq_completion)"rcu_gp"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: 00000000258d11f3 ((wq_completion)"rcu_gp"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline]
 #0: 00000000258d11f3 ((wq_completion)"rcu_gp"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline]
 #0: 00000000258d11f3 ((wq_completion)"rcu_gp"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline]
 #0: 00000000258d11f3 ((wq_completion)"rcu_gp"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0: 00000000258d11f3 ((wq_completion)"rcu_gp"){+.+.}, at: process_one_work+0x87e/0x1750 kernel/workqueue.c:2124
 #1: 000000002e93da7f ((work_completion)(&rew.rew_work)){+.+.}, at: process_one_work+0x8b4/0x1750 kernel/workqueue.c:2128
3 locks held by kworker/1:1/481:
 #0: 000000001d40af51 ((wq_completion)"events"){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline]
 #0: 000000001d40af51 ((wq_completion)"events"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: 000000001d40af51 ((wq_completion)"events"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline]
 #0: 000000001d40af51 ((wq_completion)"events"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline]
 #0: 000000001d40af51 ((wq_completion)"events"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline]
 #0: 000000001d40af51 ((wq_completion)"events"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0: 000000001d40af51 ((wq_completion)"events"){+.+.}, at: process_one_work+0x87e/0x1750 kernel/workqueue.c:2124
 #1: 00000000f4f4e51c (deferred_process_work){+.+.}, at: process_one_work+0x8b4/0x1750 kernel/workqueue.c:2128
 #2: 00000000d4eb7075 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77
1 lock held by syz-executor.2/2093:
 #0: 00000000d4eb7075 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline]
 #0: 00000000d4eb7075 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:4744
1 lock held by syz-executor.2/2107:
 #0: 00000000d4eb7075 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline]
 #0: 00000000d4eb7075 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:4744
1 lock held by syz-executor.4/2106:
 #0: 00000000d4eb7075 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77
1 lock held by syz-executor.4/2114:
 #0: 00000000d4eb7075 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline]
 #0: 00000000d4eb7075 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:4744
2 locks held by syz-executor.0/2117:
 #0: 00000000d4eb7075 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline]
 #0: 00000000d4eb7075 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:4744
 #1: 00000000c3a20a2c (rcu_preempt_state.exp_mutex){+.+.}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline]
 #1: 00000000c3a20a2c (rcu_preempt_state.exp_mutex){+.+.}, at: _synchronize_rcu_expedited+0x59e/0x7f0 kernel/rcu/tree_exp.h:667
1 lock held by syz-executor.5/2339:
 #0: 00000000d4eb7075 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline]
 #0: 00000000d4eb7075 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x40a/0xb00 net/core/rtnetlink.c:4744

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

NMI backtrace for cpu 1
CPU: 1 PID: 1039 Comm: khungtaskd Not tainted 4.19.78 #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+0x172/0x1f0 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1b0/0x1f8 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline]
 watchdog+0x9df/0xee0 kernel/hung_task.c:287
 kthread+0x354/0x420 kernel/kthread.c:246
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Sending NMI from CPU 1 to CPUs 0:
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.390 msecs
NMI backtrace for cpu 0
CPU: 0 PID: 2117 Comm: syz-executor.0 Not tainted 4.19.78 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:queued_spin_lock include/asm-generic/qspinlock.h:86 [inline]
RIP: 0010:do_raw_spin_lock+0xd5/0x240 kernel/locking/spinlock_debug.c:113
Code: 05 70 05 ae 7e 41 39 44 24 08 0f 84 8e 00 00 00 be 04 00 00 00 4c 89 e7 e8 58 83 4e 00 31 c0 ba 01 00 00 00 f0 41 0f b1 14 24 <85> c0 0f 85 8d 00 00 00 65 8b 1d 3c 05 ae 7e 48 b8 00 00 00 00 00
RSP: 0018:ffff8880ae807dc0 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff81537bd8
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffff8880ae825b80
RBP: ffff8880ae807de8 R08: 1ffff11015d04b70 R09: ffffed1015d04b71
R10: ffffed1015d04b70 R11: ffff8880ae825b83 R12: ffff8880ae825b80
R13: ffff8880ae825b88 R14: ffff8880ae825b90 R15: dffffc0000000000
FS:  00007fcc3760b700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c43164d3e0 CR3: 000000021051b000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:129 [inline]
 _raw_spin_lock_irq+0x68/0x80 kernel/locking/spinlock.c:160
 __run_hrtimer kernel/time/hrtimer.c:1400 [inline]
 __hrtimer_run_queues+0x3a3/0xdc0 kernel/time/hrtimer.c:1460
 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1518
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1067 [inline]
 smp_apic_timer_interrupt+0x111/0x550 arch/x86/kernel/apic/apic.c:1092
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:893
 </IRQ>
RIP: 0010:check_memory_region+0x1d/0x190 mm/kasan/kasan.c:266
Code: c5 66 90 66 2e 0f 1f 84 00 00 00 00 00 48 85 f6 0f 84 21 01 00 00 48 b8 ff ff ff ff ff 7f ff ff 55 0f b6 d2 48 39 c7 48 89 e5 <41> 55 41 54 53 0f 86 f6 00 00 00 4c 8d 5c 37 ff 49 89 f8 48 b8 00
RSP: 0018:ffff8881fffe69d8 EFLAGS: 00000216 ORIG_RAX: ffffffffffffff13
RAX: ffff7fffffffffff RBX: 000000000000440f RCX: ffffffff81537bd8
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffffff8865ae08
RBP: ffff8881fffe69d8 R08: 0000000000000e67 R09: 0000000000000001
R10: ffff888015f00ae8 R11: ffffffff89e5b7b8 R12: ffffffff8865ae08
R13: ffffffff8865ae10 R14: ffffffff8865ae18 R15: dffffc0000000000
 kasan_check_write+0x14/0x20 mm/kasan/kasan.c:278
 atomic_cmpxchg include/asm-generic/atomic-instrumented.h:57 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:85 [inline]
 do_raw_spin_lock+0xc8/0x240 kernel/locking/spinlock_debug.c:113
 __raw_spin_lock include/linux/spinlock_api_smp.h:143 [inline]
 _raw_spin_lock+0x37/0x40 kernel/locking/spinlock.c:144
 spin_lock include/linux/spinlock.h:329 [inline]
 nf_conntrack_lock+0x17/0x70 net/netfilter/nf_conntrack_core.c:96
 get_next_corpse net/netfilter/nf_conntrack_core.c:1917 [inline]
 nf_ct_iterate_cleanup+0x1d7/0x4e0 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+0x133/0x190 net/netfilter/nf_conntrack_core.c:2021
 masq_device_event+0xe2/0x120 net/ipv4/netfilter/nf_nat_masquerade_ipv4.c:100
 notifier_call_chain+0xc2/0x230 kernel/notifier.c:93
 __raw_notifier_call_chain kernel/notifier.c:394 [inline]
 raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:401
 call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1747
 call_netdevice_notifiers net/core/dev.c:1765 [inline]
 __dev_notify_flags+0x1e9/0x2c0 net/core/dev.c:7538
 dev_change_flags+0x101/0x150 net/core/dev.c:7572
 do_setlink+0x1604/0x34c0 net/core/rtnetlink.c:2428
 rtnl_group_changelink net/core/rtnetlink.c:2895 [inline]
 rtnl_newlink+0xd84/0x1610 net/core/rtnetlink.c:3053
 rtnetlink_rcv_msg+0x463/0xb00 net/core/rtnetlink.c:4747
 netlink_rcv_skb+0x17d/0x460 net/netlink/af_netlink.c:2454
 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:4765
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x537/0x720 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1908
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:632
 ___sys_sendmsg+0x803/0x920 net/socket.c:2115
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2153
 __do_sys_sendmsg net/socket.c:2162 [inline]
 __se_sys_sendmsg net/socket.c:2160 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2160
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459a59
Code: fd b7 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 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fcc3760ac78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459a59
RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000004
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fcc3760b6d4
R13: 00000000004c7bd7 R14: 00000000004dd968 R15: 00000000ffffffff

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/10/10 01:10 linux-4.19.y 58fce2064530 c4b9981b .config console log report ci2-linux-4-19
2019/07/25 07:08 linux-4.19.y be9b6782a9eb 32329ceb .config console log report ci2-linux-4-19
2019/06/18 08:11 linux-4.19.y 6500aa436df4 e3f76baa .config console log report ci2-linux-4-19
* Struck through repros no longer work on HEAD.