[v5.15] INFO: task hung in addrconf_verify_work

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 83655231580b Linux 5.15.159
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=15c6d5a2980000
kernel config: https://syzkaller.appspot.com/x/.config?x=ea870d7ee19c0a5c
dashboard link: https://syzkaller.appspot.com/bug?extid=9a8b3243f77e4c2545ec
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=115e25e0980000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13a20da2980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/d5444b7453a0/disk-83655231.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/76ae736a43a3/vmlinux-83655231.xz
kernel image: https://storage.googleapis.com/syzbot-assets/2540e00ba747/bzImage-83655231.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9a8b32...@syzkaller.appspotmail.com

INFO: task kworker/1:2:1066 blocked for more than 143 seconds.
Not tainted 5.15.159-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:2 state:D stack:24800 pid: 1066 ppid: 2 flags:0x00004000
Workqueue: ipv6_addrconf addrconf_verify_work
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
schedule+0x11b/0x1f0 kernel/sched/core.c:6459
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4656
process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
kthread+0x3f6/0x4f0 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300
</TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8c91fae0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
3 locks held by kworker/1:2/1066:
#0: ffff88814abe5538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc9000440fd20 ((addr_chk_work).work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffffffff8d9e7e48 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4656
2 locks held by getty/3261:
#0: ffff888024d0e098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc90002bab2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158
1 lock held by syz-executor202/3531:

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.159-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
watchdog+0xe72/0xeb0 kernel/hung_task.c:295
kthread+0x3f6/0x4f0 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300
</TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3531 Comm: syz-executor202 Not tainted 5.15.159-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
RIP: 0010:mark_lock+0xa/0x340 kernel/locking/lockdep.c:4552
Code: c1 03 38 c1 0f 8c 73 ff ff ff 4c 89 ff e8 2e 12 67 00 e9 66 ff ff ff e8 04 e5 ba 08 0f 1f 40 00 55 41 57 41 56 41 55 41 54 53 <48> 83 ec 10 49 89 f7 48 89 3c 24 49 bd 00 00 00 00 00 fc ff df 83
RSP: 0018:ffffc90002ef6448 EFLAGS: 00000002
RAX: 0000000000000001 RBX: ffff88807e7ee458 RCX: ffffffff81631938
RDX: 0000000000000008 RSI: ffff88807e7ee458 RDI: ffff88807e7ed940
RBP: ffff88807e7ed940 R08: dffffc0000000000 R09: fffffbfff1f7f032
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000001
R13: ffff88807e7ee428 R14: 0000000000000001 R15: ffff88807e7ee478
FS: 0000555556438380(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffda39b32b8 CR3: 00000000783ea000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<NMI>
</NMI>
<TASK>
mark_usage kernel/locking/lockdep.c:4512 [inline]
__lock_acquire+0xc97/0x1ff0 kernel/locking/lockdep.c:4966
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
__mutex_lock_common+0x1da/0x25a0 kernel/locking/mutex.c:596
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
tcf_idr_check_alloc+0xa1/0x380 net/sched/act_api.c:568
tcf_police_init+0x294/0x17c0 net/sched/act_police.c:84
tcf_action_init_1+0x50f/0x7f0 net/sched/act_api.c:1051
tcf_action_init+0x2f3/0x750 net/sched/act_api.c:1110
tcf_action_add net/sched/act_api.c:1522 [inline]
tc_ctl_action+0x49b/0xd00 net/sched/act_api.c:1581
rtnetlink_rcv_msg+0x993/0xee0 net/core/rtnetlink.c:5629
netlink_rcv_skb+0x1cf/0x410 net/netlink/af_netlink.c:2505
netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline]
netlink_unicast+0x7b6/0x980 net/netlink/af_netlink.c:1356
netlink_sendmsg+0xa30/0xd60 net/netlink/af_netlink.c:1924
sock_sendmsg_nosec net/socket.c:704 [inline]
__sock_sendmsg net/socket.c:716 [inline]
____sys_sendmsg+0x59e/0x8f0 net/socket.c:2431
___sys_sendmsg+0x252/0x2e0 net/socket.c:2485
__sys_sendmsg net/socket.c:2514 [inline]
__do_sys_sendmsg net/socket.c:2523 [inline]
__se_sys_sendmsg+0x19a/0x260 net/socket.c:2521
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fce9a541df9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 17 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:00007fff8059c748 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fce9a541df9
RDX: 0000000000000000 RSI: 0000000020000300 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000006
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000001
</TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.552 msecs


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