[syzbot] [net?] WARNING in ops_undo_list

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 77c5e3fdd279 Merge branch 'selftests-forwarding-fix-br_net..
git tree: net
console output: https://syzkaller.appspot.com/x/log.txt?x=14b07652580000
kernel config: https://syzkaller.appspot.com/x/.config?x=17f5c46dd78c01cf
dashboard link: https://syzkaller.appspot.com/bug?extid=5a287bcdc08104bc3132
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/90a57d114c3a/disk-77c5e3fd.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f0cb3d6cda5d/vmlinux-77c5e3fd.xz
kernel image: https://storage.googleapis.com/syzbot-assets/ad4ef00f313f/bzImage-77c5e3fd.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5a287b...@syzkaller.appspotmail.com

ip6erspan0 (unregistering): left allmulticast mode
bond7 (unregistering): (slave ip6gretap1): Releasing active interface
bond12 (unregistering): (slave geneve2): Releasing active interface
bond0 (unregistering): Released all slaves
bond1 (unregistering): Error: No native XDP support for the current bonding mode
------------[ cut here ]------------
dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL)
WARNING: net/core/dev.c:10361 at dev_xdp_uninstall net/core/dev.c:10361 [inline], CPU#0: kworker/u8:22/11031
WARNING: net/core/dev.c:10361 at unregister_netdevice_many_notify+0x1efd/0x2370 net/core/dev.c:12393, CPU#0: kworker/u8:22/11031
Modules linked in:
CPU: 0 UID: 0 PID: 11031 Comm: kworker/u8:22 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: netns cleanup_net
RIP: 0010:dev_xdp_uninstall net/core/dev.c:10361 [inline]
RIP: 0010:unregister_netdevice_many_notify+0x1efd/0x2370 net/core/dev.c:12393
Code: 0f b9 3a e9 00 ff ff ff e8 50 51 52 f8 90 0f 0b 90 e9 1d ff ff ff e8 42 51 52 f8 90 0f 0b 90 e9 a0 f3 ff ff e8 34 51 52 f8 90 <0f> 0b 90 e9 f1 f4 ff ff e8 26 51 52 f8 90 0f 0b 90 e9 4e f6 ff ff
RSP: 0018:ffffc90003b2f7c0 EFLAGS: 00010293
RAX: ffffffff8971e99c RBX: ffff888052f84c40 RCX: ffff88807896bc80
RDX: 0000000000000000 RSI: 00000000ffffffa1 RDI: 0000000000000000
RBP: ffffc90003b2f930 R08: ffffc90003b2f207 R09: 1ffff92000765e40
R10: dffffc0000000000 R11: fffff52000765e41 R12: 00000000ffffffa1
R13: ffff888052f84c38 R14: 1ffff1100a5f0988 R15: ffffc9000df67000
FS: 0000000000000000(0000) GS:ffff8881254ae000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f60871d5d58 CR3: 000000006c41c000 CR4: 00000000003526f0
Call Trace:
<TASK>
ops_exit_rtnl_list net/core/net_namespace.c:187 [inline]
ops_undo_list+0x3d3/0x940 net/core/net_namespace.c:248
cleanup_net+0x56b/0x800 net/core/net_namespace.c:704
process_one_work kernel/workqueue.c:3275 [inline]
process_scheduled_works+0xaec/0x17a0 kernel/workqueue.c:3358
worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>


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