WARNING in dev_change_net_namespace

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: c6db52a8 Linux 4.14.183
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=11f1af5a100000
kernel config: https://syzkaller.appspot.com/x/.config?x=98bbe4d18401ff4
dashboard link: https://syzkaller.appspot.com/bug?extid=396ede637da4165a137e
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

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

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+396ede...@syzkaller.appspotmail.com

RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000003
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000008
R13: 0000000000000a19 R14: 00000000004ccfd8 R15: 00007fa343dca6d4
------------[ cut here ]------------
WARNING: CPU: 0 PID: 30663 at net/core/dev.c:8405 dev_change_net_namespace net/core/dev.c:8405 [inline]
WARNING: CPU: 0 PID: 30663 at net/core/dev.c:8405 dev_change_net_namespace+0x83e/0x9f0 net/core/dev.c:8322
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 30663 Comm: syz-executor.0 Not tainted 4.14.183-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x1b2/0x283 lib/dump_stack.c:58
panic+0x1f9/0x42d kernel/panic.c:183
__warn.cold+0x2f/0x30 kernel/panic.c:547
report_bug+0x20a/0x248 lib/bug.c:186
fixup_bug arch/x86/kernel/traps.c:177 [inline]
fixup_bug arch/x86/kernel/traps.c:172 [inline]
do_error_trap+0x195/0x2d0 arch/x86/kernel/traps.c:295
invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:964
RIP: 0010:dev_change_net_namespace net/core/dev.c:8405 [inline]
RIP: 0010:dev_change_net_namespace+0x83e/0x9f0 net/core/dev.c:8322
RSP: 0018:ffff888211d27160 EFLAGS: 00010246
RAX: 0000000000040000 RBX: ffff888096d1c440 RCX: ffffc90007278000
RDX: 0000000000040000 RSI: ffffffff84fe1ace RDI: 0000000000000282
RBP: ffff888096d1c380 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff888096d1c428
R13: dffffc0000000000 R14: ffff888096d1c430 R15: ffffffff884d71c0
do_setlink+0xc0b/0x2d30 net/core/rtnetlink.c:1997
rtnl_newlink+0x11bb/0x1720 net/core/rtnetlink.c:2660
rtnetlink_rcv_msg+0x3be/0xb10 net/core/rtnetlink.c:4315
netlink_rcv_skb+0x127/0x370 net/netlink/af_netlink.c:2433
netlink_unicast_kernel net/netlink/af_netlink.c:1287 [inline]
netlink_unicast+0x437/0x610 net/netlink/af_netlink.c:1313
netlink_sendmsg+0x64a/0xbb0 net/netlink/af_netlink.c:1878
sock_sendmsg_nosec net/socket.c:646 [inline]
sock_sendmsg+0xb5/0x100 net/socket.c:656
___sys_sendmsg+0x70a/0x840 net/socket.c:2062
__sys_sendmsg+0xa3/0x120 net/socket.c:2096
SYSC_sendmsg net/socket.c:2107 [inline]
SyS_sendmsg+0x27/0x40 net/socket.c:2103
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x45ca69
RSP: 002b:00007fa343dc9c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000501700 RCX: 000000000045ca69
RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000003
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000008
R13: 0000000000000a19 R14: 00000000004ccfd8 R15: 00007fa343dca6d4
Kernel Offset: disabled
Rebooting in 86400 seconds..


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.