general protection fault in call_usermodehelper_exec_async

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: b850307b Linux 4.14.184
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=10ee6b55100000
kernel config: https://syzkaller.appspot.com/x/.config?x=ddc0f08dd6b981c5
dashboard link: https://syzkaller.appspot.com/bug?extid=a8bcf4fe6f631b24021d
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+a8bcf4...@syzkaller.appspotmail.com

general protection fault: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 0 PID: 14482 Comm: kworker/u4:2 Not tainted 4.14.184-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff88805c20a480 task.stack: ffff888000108000
RIP: 0010:call_usermodehelper_exec_async+0x1cf/0x4c0 kernel/umh.c:90
RSP: 0018:ffff88800010ff28 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 000000000000000d RSI: 0000000000000001 RDI: 0000000000000068
RBP: ffff8880a7640100 R08: 0000000000000001 R09: 0000000000000000
R10: ffff88805c20ad08 R11: ffff88805c20a480 R12: 0000000000000000
R13: 000000000000003f R14: 0000000000000000 R15: 0000000000000000
ip_tables: iptables: counters copy to user failed while replacing table
FS: 0000000000000000(0000) GS:ffff8880aec00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055e733b0e920 CR3: 000000006e99e000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Code: 21 6d 3c 44 21 f3 48 c7 c7 00 53 b5 87 89 5d 38 e8 b7 27 04 05 49 8d 7c 24 68 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 8f 02 00 00 49 8b 5c 24 68 48 85 db 74 17 e8
RIP: call_usermodehelper_exec_async+0x1cf/0x4c0 kernel/umh.c:90 RSP: ffff88800010ff28
JFS: discard option not supported on device
---[ end trace 9f43d3e20c1a5aca ]---


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[syzbot]

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