[v6.1] INFO: task hung in ip_tunnel_init_net

[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=10ea4bc2980000
kernel config: https://syzkaller.appspot.com/x/.config?x=ee57a613e7f5bf6c
dashboard link: https://syzkaller.appspot.com/bug?extid=ef59f57fbce5684d83b0
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+ef59f5...@syzkaller.appspotmail.com

INFO: task syz-executor.4:15381 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.4 state:D stack:26072 pid:15381 ppid:11031 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
ip_tunnel_init_net+0x20f/0x700 net/ipv4/ip_tunnel.c:1099
ops_init+0x35d/0x610 net/core/net_namespace.c:138
setup_net+0x4b5/0xb90 net/core/net_namespace.c:335
copy_net_ns+0x392/0x5d0 net/core/net_namespace.c:481
create_new_namespaces+0x425/0x7a0 kernel/nsproxy.c:110
unshare_nsproxy_namespaces+0x11e/0x170 kernel/nsproxy.c:226
ksys_unshare+0x580/0xb20 kernel/fork.c:3203
__do_sys_unshare kernel/fork.c:3274 [inline]
__se_sys_unshare kernel/fork.c:3272 [inline]
__x64_sys_unshare+0x34/0x40 kernel/fork.c:3272
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f9cef67cee9
RSP: 002b:00007f9cf049e0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f9cef7b3f80 RCX: 00007f9cef67cee9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000068060200
RBP: 00007f9cef6da6fe R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f9cef7b3f80 R15: 00007ffe2a475418
</TASK>
INFO: task syz-executor.3:15388 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.3 state:D stack:27240 pid:15388 ppid:10508 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


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