syzbot

INFO: task syz-executor.0:18028 blocked for more than 143 seconds.
      Not tainted 5.7.0-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0  D24824 18028   6837 0x00004004
Call Trace:
 context_switch kernel/sched/core.c:3430 [inline]
 __schedule+0x8f3/0x1f90 kernel/sched/core.c:4156
 schedule+0xd0/0x2a0 kernel/sched/core.c:4231
 schedule_timeout+0x55b/0x850 kernel/time/timer.c:1873
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x16a/0x270 kernel/sched/completion.c:138
 flush_workqueue+0x403/0x14f0 kernel/workqueue.c:2831
 rxrpc_release_sock net/rxrpc/af_rxrpc.c:885 [inline]
 rxrpc_release+0x29d/0x5e0 net/rxrpc/af_rxrpc.c:915
 __sock_release+0xcd/0x280 net/socket.c:605
 sock_close+0x18/0x20 net/socket.c:1278
 __fput+0x33e/0x880 fs/file_table.c:281
 task_work_run+0xf4/0x1b0 kernel/task_work.c:123
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x2fa/0x360 arch/x86/entry/common.c:165
 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:279 [inline]
 do_syscall_64+0x6b1/0x7d0 arch/x86/entry/common.c:305
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x45ca69
Code: Bad RIP value.
RSP: 002b:00007f9cff4c5c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 00000000004db040 RCX: 000000000045ca69
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000006
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 000000000000007d R14: 0000000000525eb2 R15: 00007f9cff4c66d4

Showing all locks held in the system:
1 lock held by khungtaskd/1145:
 #0: ffffffff899be040 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5779
1 lock held by in:imklog/6506:
 #0: ffff8880a7e5f370 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826
6 locks held by kworker/0:16/10630:
1 lock held by syz-executor.0/18028:
 #0: ffff88804b060c90 (&sb->s_type->i_mutex_key#14){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:799 [inline]
 #0: ffff88804b060c90 (&sb->s_type->i_mutex_key#14){+.+.}-{3:3}, at: __sock_release+0x86/0x280 net/socket.c:604

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

NMI backtrace for cpu 1
CPU: 1 PID: 1145 Comm: khungtaskd Not tainted 5.7.0-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+0x188/0x20d lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x231/0x27e lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline]
 watchdog+0xa8c/0x1010 kernel/hung_task.c:289
 kthread+0x388/0x470 kernel/kthread.c:268
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 10630 Comm: kworker/0:16 Not tainted 5.7.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events ipvlan_process_multicast
RIP: 0010:__lock_is_held kernel/locking/lockdep.c:4730 [inline]
RIP: 0010:lock_is_held_type+0x175/0x360 kernel/locking/lockdep.c:4996
Code: 00 00 00 00 00 fc ff df 4c 8d ad d0 08 00 00 49 c1 ec 03 49 01 c4 8b 85 c8 08 00 00 85 c0 7f 27 e9 0c 01 00 00 41 0f b6 04 24 <41> 83 c7 01 84 c0 74 08 3c 03 0f 8e 63 01 00 00 44 3b bd c8 08 00
RSP: 0018:ffffc90000007338 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffffff8a592ea8 RCX: ffffffff86d54a05
RDX: 0000000000000000 RSI: ffffffff8a592ea8 RDI: ffff888089352b02
RBP: ffff8880893521c0 R08: ffff8880893521c0 R09: ffffc900000075e8
R10: ffff8880ae638c1b R11: ffffed1015cc7183 R12: ffffed101126a551
R13: ffff888089352a90 R14: ffff888089352ae0 R15: 0000000000000002
FS:  0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4e297f5ab4 CR3: 0000000093dcb000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 lock_is_held include/linux/lockdep.h:425 [inline]
 lockdep_rtnl_is_held+0x17/0x30 net/core/rtnetlink.c:137
 __in6_dev_get include/net/addrconf.h:310 [inline]
 ip6_ignore_linkdown include/net/addrconf.h:401 [inline]
 find_match+0x2d0/0xc90 net/ipv6/route.c:749
 __find_rr_leaf+0x137/0x980 net/ipv6/route.c:837
 find_rr_leaf net/ipv6/route.c:858 [inline]
 rt6_select net/ipv6/route.c:902 [inline]
 fib6_table_lookup+0x629/0xcc0 net/ipv6/route.c:2189
 ip6_pol_route+0x1c9/0xc20 net/ipv6/route.c:2225
 __fib6_rule_action net/ipv6/fib6_rules.c:229 [inline]
 fib6_rule_action+0x2d6/0xae0 net/ipv6/fib6_rules.c:261
 fib_rules_lookup+0x3a4/0xc30 net/core/fib_rules.c:301
 fib6_rule_lookup+0x375/0x750 net/ipv6/fib6_rules.c:106
 ip6_route_input+0x5f0/0xa40 net/ipv6/route.c:2464
 ip6_rcv_finish_core.isra.0+0x168/0x580 net/ipv6/ip6_input.c:63
 ip6_rcv_finish+0x176/0x310 net/ipv6/ip6_input.c:74
 NF_HOOK include/linux/netfilter.h:307 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 ipv6_rcv+0xf8/0x3f0 net/ipv6/ip6_input.c:307
 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5268
 __netif_receive_skb+0x27/0x1c0 net/core/dev.c:5382
 process_backlog+0x21e/0x7a0 net/core/dev.c:6226
 napi_poll net/core/dev.c:6671 [inline]
 net_rx_action+0x4c2/0x1070 net/core/dev.c:6739
 __do_softirq+0x26c/0x9f7 kernel/softirq.c:292
 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1082
 </IRQ>
 do_softirq.part.0+0x10f/0x160 kernel/softirq.c:337
 do_softirq kernel/softirq.c:329 [inline]
 __local_bh_enable_ip+0x20e/0x270 kernel/softirq.c:189
 local_bh_enable include/linux/bottom_half.h:32 [inline]
 ipvlan_process_multicast+0x7e6/0xca0 drivers/net/ipvlan/ipvlan_core.c:279
 process_one_work+0x965/0x16a0 kernel/workqueue.c:2268
 worker_thread+0x96/0xe20 kernel/workqueue.c:2414
 kthread+0x388/0x470 kernel/kthread.c:268
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351