WARNING in clusterip_net_exit

[syzbot]

Hello,

syzbot hit the following crash on upstream commit
c02be2334e7523903cc15b5258a48b85b5de6cbc (Wed Feb 28 19:40:51 2018 +0000)
Merge tag 'xfs-4.16-fixes-2' of
git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Unfortunately, I don't have any reproducer for this crash yet.
Raw console output is attached.
compiler: gcc (GCC) 7.1.1 20170620
.config is attached.
CC: [core...@netfilter.org da...@davemloft.net f...@strlen.de
kad...@blackhole.kfki.hu kuz...@ms2.inr.ac.ru linux-...@vger.kernel.org
net...@vger.kernel.org netfilt...@vger.kernel.org pa...@netfilter.org
yosh...@linux-ipv6.org]

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+3924bf...@syzkaller.appspotmail.com
It will help syzbot understand when the bug is fixed. See footer for
details.
If you forward the report, please keep this part and the footer.

bond0 (unregistering): Released all slaves
WARNING: CPU: 1 PID: 88 at net/ipv4/netfilter/ipt_CLUSTERIP.c:835
clusterip_net_exit+0x368/0x3e0 net/ipv4/netfilter/ipt_CLUSTERIP.c:835
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 88 Comm: kworker/u4:3 Not tainted 4.16.0-rc3+ #333
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x194/0x24d lib/dump_stack.c:53
panic+0x1e4/0x41c kernel/panic.c:183
__warn+0x1dc/0x200 kernel/panic.c:547
report_bug+0x211/0x2d0 lib/bug.c:184
fixup_bug.part.11+0x37/0x80 arch/x86/kernel/traps.c:178
fixup_bug arch/x86/kernel/traps.c:247 [inline]
do_error_trap+0x2d7/0x3e0 arch/x86/kernel/traps.c:296
do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:315
invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:986
RIP: 0010:clusterip_net_exit+0x368/0x3e0
net/ipv4/netfilter/ipt_CLUSTERIP.c:835
RSP: 0018:ffff8801d901f1a8 EFLAGS: 00010293
RAX: ffff8801d9690040 RBX: 1ffff1003b203e36 RCX: ffffffff84e2aaa8
RDX: 0000000000000000 RSI: 1ffff1003b203e0c RDI: ffffed003b203df8
RBP: ffff8801d901f278 R08: 1ffff1003b203d7e R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801d901f250
R13: 1ffff1003b203e3a R14: ffff8801b28b9380 R15: ffff8801b285e0c0
ops_exit_list.isra.6+0xae/0x150 net/core/net_namespace.c:142
cleanup_net+0x6a1/0xcb0 net/core/net_namespace.c:517
process_one_work+0xc47/0x1bb0 kernel/workqueue.c:2113
worker_thread+0x223/0x1990 kernel/workqueue.c:2247
kthread+0x33c/0x400 kernel/kthread.c:238
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:406
Dumping ftrace buffer:
(ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..


---
This bug is generated by a dumb bot. It may contain errors.
See https://goo.gl/tpsmEJ for details.
Direct all questions to syzk...@googlegroups.com.

syzbot will keep track of this bug report.
If you forgot to add the Reported-by tag, once the fix for this bug is
merged
into any tree, please reply to this email with:
#syz fix: exact-commit-title
To mark this as a duplicate of another syzbot report, please reply with:
#syz dup: exact-subject-of-another-report
If it's a one-off invalid bug report, please reply with:
#syz invalid
Note: if the crash happens again, it will cause creation of a new bug
report.
Note: all commands must start from beginning of the line in the email body.
To upstream this report, please reply with:
#syz upstream

[Dmitry Vyukov]

too old, there were lots of fixes in clusterip since then

#syz invalid

> --
> You received this message because you are subscribed to the Google Groups
> "syzkaller-upstream-moderation" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to syzkaller-upstream-m...@googlegroups.com.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/syzkaller-upstream-moderation/001a1144b8e625f71a05665034e0%40google.com.
> For more options, visit https://groups.google.com/d/optout.