audit: type=1400 audit(1521402469.495:6): avc:  denied  { write } for  pid=3769 comm="syzkaller165316" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_netfilter_socket permissive=1
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: 1 PID: 3769 Comm: syzkaller165316 Not tainted 4.4.120-gd63fdf6 #28
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801c5e24800 task.stack: ffff8801d2550000
RIP: 0010:[<ffffffff82f89d90>]  [<ffffffff82f89d90>] netlink_getsockbyportid net/netlink/af_netlink.c:1102 [inline]
RIP: 0010:[<ffffffff82f89d90>]  [<ffffffff82f89d90>] netlink_unicast+0x1c0/0x760 net/netlink/af_netlink.c:1287
RSP: 0018:ffff8801d2557778  EFLAGS: 00010293
RAX: dffffc0000000048 RBX: dffffc0000000000 RCX: ffffffff82f89d89
RDX: 0000000000000000 RSI: 00000000024000c0 RDI: ffff8801d9067998
RBP: ffff8801d2557838 R08: ffffed0038ef5b76 R09: ffffed0038ef5b76
R10: 0000000000000004 R11: ffffed0038ef5b75 R12: 0000000000000000
R13: dffffc0000000000 R14: ffff8801d90678c0 R15: dffffc0000000006
FS:  00000000009bc880(0063) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000c80 CR3: 00000001d9824000 CR4: 0000000000160670
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 1ffff1003a4aaef6 ffff8801c77adb80 0000000000000240 0000000000000030
 1ffff1003a4aaef6 dffffc0000000048 0000000000000eb9 0000000041b58ab3
 ffffffff84001503 ffffffff82f89bd0 ffff8801d90678c0 0000000000000000
Call Trace:
 [<ffffffff82f8b1b1>] netlink_ack+0x231/0x4b0 net/netlink/af_netlink.c:2322
 [<ffffffff82f98fd2>] nfnetlink_rcv_batch net/netfilter/nfnetlink.c:319 [inline]
 [<ffffffff82f98fd2>] nfnetlink_rcv+0xaa2/0x1070 net/netfilter/nfnetlink.c:477
 [<ffffffff82f8a0f2>] netlink_unicast_kernel net/netlink/af_netlink.c:1267 [inline]
 [<ffffffff82f8a0f2>] netlink_unicast+0x522/0x760 net/netlink/af_netlink.c:1293
 [<ffffffff82f8ac18>] netlink_sendmsg+0x8e8/0xc50 net/netlink/af_netlink.c:1847
 [<ffffffff82deba6a>] sock_sendmsg_nosec net/socket.c:625 [inline]
 [<ffffffff82deba6a>] sock_sendmsg+0xca/0x110 net/socket.c:635
 [<ffffffff82ded641>] ___sys_sendmsg+0x6c1/0x7c0 net/socket.c:1962
 [<ffffffff82def693>] __sys_sendmsg+0xd3/0x190 net/socket.c:1996
 [<ffffffff82def77d>] SYSC_sendmsg net/socket.c:2007 [inline]
 [<ffffffff82def77d>] SyS_sendmsg+0x2d/0x50 net/socket.c:2003
 [<ffffffff8377395f>] entry_SYSCALL_64_fastpath+0x1c/0x98
Code: e7 6f 3d fe 48 8d 55 98 4c 89 e1 4c 89 f6 48 89 df e8 95 f7 ff ff 83 f8 01 0f 85 e1 03 00 00 e8 c7 6f 3d fe 48 8b 85 68 ff ff ff <0f> b6 00 84 c0 74 08 3c 03 0f 8e 63 05 00 00 41 80 3f 00 41 0f 
RIP  [<ffffffff82f89d90>] netlink_getsockbyportid net/netlink/af_netlink.c:1102 [inline]
RIP  [<ffffffff82f89d90>] netlink_unicast+0x1c0/0x760 net/netlink/af_netlink.c:1287
 RSP <ffff8801d2557778>
---[ end trace e7d2833f3108d685 ]---
Kernel panic - not syncing: Fatal exception
Dumping ftrace buffer:
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Kernel Offset: disabled
Rebooting in 86400 seconds..