[v6.1] INFO: task hung in sit_exit_batch_net

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: eb44d83053d6 Linux 6.1.94
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=166c8256980000
kernel config: https://syzkaller.appspot.com/x/.config?x=6039f42ac286acdd
dashboard link: https://syzkaller.appspot.com/bug?extid=fa7d54d0a43030567c75
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/694155cbaf06/disk-eb44d830.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/5e703076e2b1/vmlinux-eb44d830.xz
kernel image: https://storage.googleapis.com/syzbot-assets/967e214f1ac1/bzImage-eb44d830.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+fa7d54...@syzkaller.appspotmail.com

INFO: task kworker/u4:2:41 blocked for more than 143 seconds.
Not tainted 6.1.94-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:2 state:D stack:22336 pid:41 ppid:2 flags:0x00004000
Workqueue: netns cleanup_net
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
sit_exit_batch_net+0xc0/0x480 net/ipv6/sit.c:1883
ops_exit_list net/core/net_namespace.c:177 [inline]
cleanup_net+0x763/0xb60 net/core/net_namespace.c:604
process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292


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