WARNING in xfrm_add_pol_expire

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 7902639f
git tree: android-4.4
console output: https://syzkaller.appspot.com/x/log.txt?x=14f2f1a9800000
kernel config: https://syzkaller.appspot.com/x/.config?x=44509e3077d6939
dashboard link: https://syzkaller.appspot.com/bug?extid=1cd3957872fcf0940b42
compiler: gcc (GCC) 7.1.1 20170620
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13c8dec9800000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13bf8e39800000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+1cd395...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 1 PID: 3319 at net/xfrm/xfrm_user.c:2075
xfrm_add_pol_expire+0x5b3/0x6d0 net/xfrm/xfrm_user.c:2075()
Don't know what to do with soft policy expire
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 3319 Comm: syzkaller109521 Not tainted 4.4.111-g7902639 #25
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
0000000000000000 9dcae297e62f77fc ffff8800b4ec7420 ffffffff81d0509d
ffffffff83842f60 ffff8800b4ec74f8 ffffffff83d0a280 0000000000000009
000000000000081b ffff8800b4ec74e8 ffffffff81419a3a 0000000041b58ab3
Call Trace:
[<ffffffff81d0509d>] __dump_stack lib/dump_stack.c:15 [inline]
[<ffffffff81d0509d>] dump_stack+0xc1/0x124 lib/dump_stack.c:51
[<ffffffff81419a3a>] panic+0x1aa/0x388 kernel/panic.c:112
[<ffffffff8112d7c5>] warn_slowpath_common+0x125/0x140 kernel/panic.c:455
[<ffffffff8112d8a1>] warn_slowpath_fmt+0xc1/0x110 kernel/panic.c:471
[<ffffffff832d5da3>] xfrm_add_pol_expire+0x5b3/0x6d0
net/xfrm/xfrm_user.c:2075
[<ffffffff832d1d4c>] xfrm_user_rcv_msg+0x41c/0x6b0
net/xfrm/xfrm_user.c:2525
[<ffffffff82f8c66e>] netlink_rcv_skb+0x13e/0x370
net/netlink/af_netlink.c:2349
[<ffffffff832ce27f>] xfrm_netlink_rcv+0x6f/0x90 net/xfrm/xfrm_user.c:2533
[<ffffffff82f8b1f2>] netlink_unicast_kernel net/netlink/af_netlink.c:1267
[inline]
[<ffffffff82f8b1f2>] netlink_unicast+0x522/0x760
net/netlink/af_netlink.c:1293
[<ffffffff82f8bd18>] netlink_sendmsg+0x8e8/0xc50
net/netlink/af_netlink.c:1847
[<ffffffff82ded98a>] sock_sendmsg_nosec net/socket.c:625 [inline]
[<ffffffff82ded98a>] sock_sendmsg+0xca/0x110 net/socket.c:635
[<ffffffff82def561>] ___sys_sendmsg+0x6c1/0x7c0 net/socket.c:1962
[<ffffffff82df15b3>] __sys_sendmsg+0xd3/0x190 net/socket.c:1996
[<ffffffff82df169d>] SYSC_sendmsg net/socket.c:2007 [inline]
[<ffffffff82df169d>] SyS_sendmsg+0x2d/0x50 net/socket.c:2003
[<ffffffff83775899>] entry_SYSCALL_64_fastpath+0x16/0x92
Dumping ftrace buffer:
(ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..


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