WARNING in pfkey_sock_destruct

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    10dc890d4228 Merge tag 'pinctrl-v4.19-3' of git://git.kern..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=126e7111400000
kernel config:  https://syzkaller.appspot.com/x/.config?x=5fa12be50bca08d8
dashboard link: https://syzkaller.appspot.com/bug?extid=4acf0d9092f91bb60431
compiler:       gcc (GCC) 8.0.1 20180413 (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+4acf0d9092f91bb60431@xxxxxxxxxxxxxxxxxxxxxxxxx

WARNING: CPU: 1 PID: 18415 at net/key/af_key.c:111  
pfkey_sock_destruct+0x574/0x610 net/key/af_key.c:111
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 18415 Comm: syz-executor3 Not tainted 4.19.0-rc4+ #28
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c4/0x2b4 lib/dump_stack.c:113
 panic+0x238/0x4e7 kernel/panic.c:184
 __warn.cold.8+0x163/0x1ba kernel/panic.c:536
 report_bug+0x254/0x2d0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 do_error_trap+0x1fc/0x4d0 arch/x86/kernel/traps.c:296
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:993
RIP: 0010:pfkey_sock_destruct+0x574/0x610 net/key/af_key.c:111
Code: 00 48 c7 c7 a0 14 b4 88 c6 05 9e 48 40 03 01 e8 6d bc 80 fa e9 70 fc  
ff ff e8 78 69 9e fa 0f 0b e9 a8 fe ff ff e8 6c 69 9e fa <0f> 0b e9 ed fd  
ff ff 48 89 c7 e8 2d ca e1 fa e9 40 fe ff ff 4c 89
RSP: 0018:ffff880199627660 EFLAGS: 00010293
RAX: ffff88011e2a0680 RBX: ffff8801c5053100 RCX: ffffffff86e078fa
RDX: 0000000000000000 RSI: ffffffff86e07b14 RDI: 0000000000000005
RBP: ffff880199627770 R08: ffff88011e2a0680 R09: ffffed0038a0a65b
R10: ffffed0038a0a65b R11: ffff8801c50532db R12: 1ffff100332c4ecd
R13: ffff880199627748 R14: 1ffff100332c4ed1 R15: ffff8801cd7d4b40
 __sk_destruct+0x115/0xbd0 net/core/sock.c:1560
 sk_destruct+0x78/0x90 net/core/sock.c:1595
 __sk_free+0xcf/0x300 net/core/sock.c:1606
 sk_free+0x42/0x50 net/core/sock.c:1617
 sock_put include/net/sock.h:1691 [inline]
 pfkey_release+0x409/0x570 net/key/af_key.c:194
 __sock_release+0xd7/0x250 net/socket.c:579
 sock_close+0x19/0x20 net/socket.c:1141
 __fput+0x385/0xa30 fs/file_table.c:278
 ____fput+0x15/0x20 fs/file_table.c:309
 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:193 [inline]
 exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x411151
Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 34 19 00 00 c3 48  
83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48  
89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01
kobject: 'loop4' (000000003d24b0c2): kobject_uevent_env
RSP: 002b:00007ffd93469000 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
kobject: 'loop4' (000000003d24b0c2): fill_kobj_path: path  
= '/devices/virtual/block/loop4'
RAX: 0000000000000000 RBX: 0000000000000006 RCX: 0000000000411151
RDX: 0000000000000000 RSI: 00000000007317f8 RDI: 0000000000000005
RBP: 0000000000000000 R08: 00000000000000a0 R09: ffffffffffffffff
R10: 000000000072bfa0 R11: 0000000000000293 R12: 000000000000000b
R13: 000000000006a9d7 R14: 0000000000000167 R15: badc0ffeebadface
Kernel Offset: disabled
Rebooting in 86400 seconds..


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