kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory accessgeneral protection fault: 0000 [#1] PREEMPT SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 31830 Comm: syz-executor0 Not tainted 4.4.145-g2241aa9 #78
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8800b5566000 task.stack: ffff8800b1860000
RIP: 0010:[<ffffffff833da7ca>]  [<ffffffff833da7ca>] xfrm_policy_ok net/xfrm/xfrm_policy.c:2382 [inline]
RIP: 0010:[<ffffffff833da7ca>]  [<ffffffff833da7ca>] __xfrm_policy_check+0xc9a/0x1b30 net/xfrm/xfrm_policy.c:2558
RSP: 0018:ffff8801db207570  EFLAGS: 00010202
RAX: 0000000000000006 RBX: 0000000000000002 RCX: ffff8800b5566000
RDX: 0000000000000004 RSI: ffffffff833da799 RDI: 0000000000000034
RBP: ffff8801db2077b8 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
R13: ffff8801db2076b0 R14: dffffc0000000000 R15: 0000000000000000
FS:  00007f479c3f7700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000b1f4a000 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffffffff833d9c6f ffff8801db207610 ffff8801db2076a8 0000000200000001
 ffff8801db207618 ffff8800b5d581a8 0000000200021da0 ffff8801db2076b8
 ffff8801beb20880 ffff880000000002 1ffff1003b640ebe ffff8801db207710
Call Trace:
 <IRQ> 
 [<ffffffff832d8c46>] __xfrm_policy_check2 include/net/xfrm.h:1067 [inline]
 [<ffffffff832d8c46>] xfrm_policy_check include/net/xfrm.h:1076 [inline]
 [<ffffffff832d8c46>] xfrm4_policy_check include/net/xfrm.h:1081 [inline]
 [<ffffffff832d8c46>] udp_queue_rcv_skb+0x6e6/0x1580 net/ipv4/udp.c:1520
 [<ffffffff832db2a9>] __udp4_lib_rcv+0xbe9/0x23e0 net/ipv4/udp.c:1830
 [<ffffffff832de111>] udp_rcv+0x21/0x30 net/ipv4/udp.c:2043
 [<ffffffff832061e7>] ip_local_deliver_finish+0x257/0xa60 net/ipv4/ip_input.c:216
 [<ffffffff83208761>] NF_HOOK_THRESH include/linux/netfilter.h:226 [inline]
 [<ffffffff83208761>] NF_HOOK include/linux/netfilter.h:249 [inline]
 [<ffffffff83208761>] ip_local_deliver+0x1f1/0x380 net/ipv4/ip_input.c:257
 [<ffffffff8320704a>] dst_input include/net/dst.h:504 [inline]
 [<ffffffff8320704a>] ip_rcv_finish+0x65a/0x1640 net/ipv4/ip_input.c:365
 [<ffffffff832092d4>] NF_HOOK_THRESH include/linux/netfilter.h:226 [inline]
 [<ffffffff832092d4>] NF_HOOK include/linux/netfilter.h:249 [inline]
 [<ffffffff832092d4>] ip_rcv+0x9e4/0x1190 net/ipv4/ip_input.c:455
 [<ffffffff82f83666>] __netif_receive_skb_core+0x12d6/0x2940 net/core/dev.c:4019
 [<ffffffff82f84d2b>] __netif_receive_skb+0x5b/0x1c0 net/core/dev.c:4054
 [<ffffffff82f89246>] process_backlog+0x216/0x6a0 net/core/dev.c:4647
 [<ffffffff82f86102>] napi_poll net/core/dev.c:4885 [inline]
 [<ffffffff82f86102>] net_rx_action+0x3a2/0xdb0 net/core/dev.c:4950
 [<ffffffff838cb9fc>] __do_softirq+0x22c/0xa1a kernel/softirq.c:273
 [<ffffffff838c975c>] do_softirq_own_stack+0x1c/0x30 arch/x86/entry/entry_64.S:929
 <EOI> 
 [<ffffffff8113fbb4>] do_softirq.part.16+0x54/0x60 kernel/softirq.c:317
 [<ffffffff811418a9>] do_softirq+0x19/0x20 kernel/softirq.c:320
 [<ffffffff82f8160c>] netif_rx_ni+0xec/0x3a0 net/core/dev.c:3653
 [<ffffffff82756d47>] tun_get_user+0xbe7/0x2410 drivers/net/tun.c:1264
 [<ffffffff82758785>] tun_chr_write_iter+0xd5/0x190 drivers/net/tun.c:1283
 [<ffffffff8151fc4c>] do_iter_readv_writev+0x13c/0x1e0 fs/read_write.c:664
 [<ffffffff81521370>] do_readv_writev+0x2e0/0x6e0 fs/read_write.c:808
 [<ffffffff8152189b>] vfs_writev+0x7b/0xb0 fs/read_write.c:847
 [<ffffffff81523d69>] SYSC_writev fs/read_write.c:880 [inline]
 [<ffffffff81523d69>] SyS_writev+0xd9/0x250 fs/read_write.c:872
 [<ffffffff838c84e5>] entry_SYSCALL_64_fastpath+0x22/0x9e
Code: ff 48 c1 e8 03 42 80 3c 30 00 0f 85 11 0d 00 00 48 8b 85 f0 fd ff ff 48 8b 18 48 8d 7b 32 48 89 f8 48 89 fa 48 c1 e8 03 83 e2 07 <42> 0f b6 04 30 38 d0 7f 08 84 c0 0f 85 11 0d 00 00 0f b6 43 32 
RIP  [<ffffffff833da7ca>] xfrm_policy_ok net/xfrm/xfrm_policy.c:2382 [inline]
RIP  [<ffffffff833da7ca>] __xfrm_policy_check+0xc9a/0x1b30 net/xfrm/xfrm_policy.c:2558
 RSP <ffff8801db207570>
---[ end trace 81edffbb1c1c17b0 ]---