syzbot

watchdog: BUG: soft lockup - CPU#1 stuck for 22s! [syz-executor.4:26310]
Modules linked in:
irq event stamp: 5107
hardirqs last  enabled at (5106): [<ffffffff81003ce4>] trace_hardirqs_on_thunk+0x1a/0x1c
hardirqs last disabled at (5107): [<ffffffff81003d00>] trace_hardirqs_off_thunk+0x1a/0x1c
softirqs last  enabled at (168): [<ffffffff86a4ea3f>] spin_unlock include/linux/spinlock.h:369 [inline]
softirqs last  enabled at (168): [<ffffffff86a4ea3f>] nf_conntrack_double_unlock net/netfilter/nf_conntrack_core.c:119 [inline]
softirqs last  enabled at (168): [<ffffffff86a4ea3f>] __nf_conntrack_confirm+0x156f/0x2ff0 net/netfilter/nf_conntrack_core.c:998
softirqs last disabled at (170): [<ffffffff87020872>] lwtunnel_xmit_redirect include/net/lwtunnel.h:92 [inline]
softirqs last disabled at (170): [<ffffffff87020872>] ip6_finish_output2+0x1f2/0x2290 net/ipv6/ip6_output.c:106
CPU: 1 PID: 26310 Comm: syz-executor.4 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x50 kernel/kcov.c:97
Code: ff 48 89 df e8 11 dd 35 00 e9 ab fe ff ff 4c 89 ef e8 04 dd 35 00 e9 23 fe ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <48> 8b 34 24 65 48 8b 04 25 c0 df 01 00 65 8b 15 cc 59 9f 7e 81 e2
RSP: 0018:ffff888035a37048 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000002 RBX: ffff8880a8527200 RCX: ffffffff8699cbf7
RDX: 00000000c2089614 RSI: ffff8880ae4be4c0 RDI: 0000000000000005
RBP: ffff8880aabf91f8 R08: ffffffff8c665058 R09: 0000000000000000
R10: 0000000000000005 R11: ffffffff8c66505b R12: dffffc0000000000
R13: 00000000c2089614 R14: ffff8880a8527480 R15: ffff8880a8527490
FS:  00007f231626c700(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2317d0edf0 CR3: 00000000abb0a000 CR4: 00000000003406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 fq_dequeue+0x75b/0x12b0 net/sched/sch_fq.c:487
 dequeue_skb net/sched/sch_generic.c:282 [inline]
 qdisc_restart net/sched/sch_generic.c:385 [inline]
 __qdisc_run+0x1b9/0x1640 net/sched/sch_generic.c:403
 __dev_xmit_skb net/core/dev.c:3500 [inline]
 __dev_queue_xmit+0x1518/0x2e00 net/core/dev.c:3807
 neigh_resolve_output+0x55a/0x910 net/core/neighbour.c:1374
 neigh_output include/net/neighbour.h:501 [inline]
 ip6_finish_output2+0x113d/0x2290 net/ipv6/ip6_output.c:120
 ip6_finish_output+0x89b/0x10f0 net/ipv6/ip6_output.c:192
 NF_HOOK_COND include/linux/netfilter.h:278 [inline]
 ip6_output+0x205/0x770 net/ipv6/ip6_output.c:209
 dst_output include/net/dst.h:455 [inline]
 ip6_local_out+0xaf/0x170 net/ipv6/output_core.c:160
 ip6_send_skb+0xb3/0x300 net/ipv6/ip6_output.c:1741
 udp_v6_send_skb+0x7d7/0x1610 net/ipv6/udp.c:1114
 udpv6_sendmsg+0x236b/0x2ae0 net/ipv6/udp.c:1411
 inet_sendmsg+0x132/0x5a0 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg+0xc3/0x120 net/socket.c:661
 ___sys_sendmsg+0x3b3/0x8e0 net/socket.c:2227
 __sys_sendmmsg+0x195/0x470 net/socket.c:2322
 __do_sys_sendmmsg net/socket.c:2351 [inline]
 __se_sys_sendmmsg net/socket.c:2348 [inline]
 __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2348
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f2317cfa0c9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f231626c168 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f2317e19f80 RCX: 00007f2317cfa0c9
RDX: 0000000000000001 RSI: 0000000020000140 RDI: 0000000000000003
RBP: 00007f2317d55ae9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffecd25a92f R14: 00007f231626c300 R15: 0000000000022000
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60