[v6.1] INFO: task hung in ipv6_sock_mc_close

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 88690811da69 Linux 6.1.92
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1620fbfc980000
kernel config: https://syzkaller.appspot.com/x/.config?x=ee57a613e7f5bf6c
dashboard link: https://syzkaller.appspot.com/bug?extid=9c466643cca32cbf6072
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/8b45ba80e02a/disk-88690811.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ca769d644800/vmlinux-88690811.xz
kernel image: https://storage.googleapis.com/syzbot-assets/26a1d8aecbf6/bzImage-88690811.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9c4666...@syzkaller.appspotmail.com

INFO: task syz-executor.2:5763 blocked for more than 143 seconds.
Not tainted 6.1.92-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2 state:D stack:25000 pid:5763 ppid:4369 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x142d/0x4550 kernel/sched/core.c:6558
schedule+0xbf/0x180 kernel/sched/core.c:6634
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6693
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x6b9/0xd80 kernel/locking/mutex.c:747
ipv6_sock_mc_close+0xc5/0x130 net/ipv6/mcast.c:354
inet6_release+0x43/0x70 net/ipv6/af_inet6.c:488
__sock_release net/socket.c:654 [inline]
sock_close+0xcd/0x230 net/socket.c:1400
__fput+0x3b7/0x890 fs/file_table.c:320
task_work_run+0x246/0x300 kernel/task_work.c:179
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f0dbcc7bdda
RSP: 002b:00007ffc52816330 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 000000000000000b RCX: 00007f0dbcc7bdda
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000000000a
RBP: 00007f0dbcdb59a0 R08: 00000000818e5adc R09: 0000000000000010
R10: 0000000000000033 R11: 0000000000000293 R12: 0000000000027f52
R13: 00007f0dbcdb42ec R14: 0000000000000032 R15: 00007f0dbcdb59a0
</TASK>
INFO: task syz-executor.1:5782 blocked for more than 143 seconds.
Not tainted 6.1.92-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.1 state:D stack:25832 pid:5782 ppid:4181 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x142d/0x4550 kernel/sched/core.c:6558
schedule+0xbf/0x180 kernel/sched/core.c:6634
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6693


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