audit: type=1400 audit(1579282739.943:38): avc: denied { write } for pid=7391 comm="syz-executor257" 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: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] PREEMPT SMP KASAN Modules linked in: CPU: 1 PID: 7391 Comm: syz-executor257 Not tainted 4.14.165-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8880782344c0 task.stack: ffff8880a9bb0000 RIP: 0010:nfnetlink_parse_nat net/netfilter/nf_nat_core.c:747 [inline] RIP: 0010:nfnetlink_parse_nat_setup+0x212/0x3b0 net/netfilter/nf_nat_core.c:784 RSP: 0018:ffff8880a9bb7208 EFLAGS: 00010246 RAX: ffffffff854cfd10 RBX: ffff8880a9bb7290 RCX: 0000000000000000 RDX: 1ffffffff0a99fa9 RSI: ffff8880a9bb7240 RDI: ffff8880a9bb7290 RBP: ffff8880a9bb7308 R08: 1ffff11015376e52 R09: ffff8880a9bb7290 R10: ffffed1015376e57 R11: ffff8880a9bb72bf R12: ffff88807c629dc0 R13: 0000000000000000 R14: ffff8880a9bb72e0 R15: ffff8880a9bb7240 FS: 00000000009d0880(0000) GS:ffff8880aed00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055bb38a011b0 CR3: 000000008f81e000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ctnetlink_parse_nat_setup+0x76/0x4a0 net/netfilter/nf_conntrack_netlink.c:1421 ctnetlink_setup_nat net/netfilter/nf_conntrack_netlink.c:1491 [inline] ctnetlink_create_conntrack+0x468/0x10c0 net/netfilter/nf_conntrack_netlink.c:1840 ctnetlink_new_conntrack+0x4af/0xcc0 net/netfilter/nf_conntrack_netlink.c:1964 nfnetlink_rcv_msg+0xa08/0xc00 net/netfilter/nfnetlink.c:214 netlink_rcv_skb+0x14f/0x3c0 net/netlink/af_netlink.c:2432 nfnetlink_rcv+0x1ab/0x1650 net/netfilter/nfnetlink.c:515 netlink_unicast_kernel net/netlink/af_netlink.c:1286 [inline] netlink_unicast+0x44d/0x650 net/netlink/af_netlink.c:1312 netlink_sendmsg+0x7c4/0xc60 net/netlink/af_netlink.c:1877 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xce/0x110 net/socket.c:656 ___sys_sendmsg+0x70a/0x840 net/socket.c:2062 __sys_sendmsg+0xb9/0x140 net/socket.c:2096 SYSC_sendmsg net/socket.c:2107 [inline] SyS_sendmsg+0x2d/0x50 net/socket.c:2103 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x440479 RSP: 002b:00007ffe2b7a6148 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440479 RDX: 0000000000000000 RSI: 0000000020000280 RDI: 0000000000000003 RBP: 00000000006ca018 R08: 0000000000000014 R09: 00000000004002c8 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000401d00 R13: 0000000000401d90 R14: 0000000000000000 R15: 0000000000000000 Code: 8d 78 38 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 98 01 00 00 48 8b 85 10 ff ff ff 4c 89 fe 48 89 df 50 38 85 c0 0f 88 01 01 00 00 e8 be 5f 14 fc 4d 8b 76 c8 4d RIP: nfnetlink_parse_nat net/netfilter/nf_nat_core.c:747 [inline] RSP: ffff8880a9bb7208 RIP: nfnetlink_parse_nat_setup+0x212/0x3b0 net/netfilter/nf_nat_core.c:784 RSP: ffff8880a9bb7208 ---[ end trace bd47beb6b9063e0a ]---