audit: type=1400 audit(1580770493.776:38): avc:  denied  { write } for  pid=8312 comm="syz-executor464" 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
BUG: KASAN: global-out-of-bounds in nfnetlink_parse_nat net/netfilter/nf_nat_core.c:847 [inline]
BUG: KASAN: global-out-of-bounds in nfnetlink_parse_nat_setup+0x436/0x450 net/netfilter/nf_nat_core.c:884
Read of size 8 at addr ffffffff884faaf8 by task syz-executor464/8312

CPU: 0 PID: 8312 Comm: syz-executor464 Not tainted 4.19.101-syzkaller #0
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+0x197/0x210 lib/dump_stack.c:118
 print_address_description.cold+0x5/0x20d mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report mm/kasan/report.c:412 [inline]
 kasan_report.cold+0x8c/0x2ba mm/kasan/report.c:396
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
 nfnetlink_parse_nat net/netfilter/nf_nat_core.c:847 [inline]
 nfnetlink_parse_nat_setup+0x436/0x450 net/netfilter/nf_nat_core.c:884
 ctnetlink_parse_nat_setup+0xc5/0x660 net/netfilter/nf_conntrack_netlink.c:1521
 ctnetlink_setup_nat net/netfilter/nf_conntrack_netlink.c:1591 [inline]
 ctnetlink_create_conntrack+0x4ea/0x1300 net/netfilter/nf_conntrack_netlink.c:1984
 ctnetlink_new_conntrack+0x527/0xe50 net/netfilter/nf_conntrack_netlink.c:2114
 nfnetlink_rcv_msg+0xd0d/0xfcf net/netfilter/nfnetlink.c:228
 netlink_rcv_skb+0x17d/0x460 net/netlink/af_netlink.c:2454
 nfnetlink_rcv+0x1c0/0x460 net/netfilter/nfnetlink.c:560
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x53a/0x730 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1908
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:632
 ___sys_sendmsg+0x803/0x920 net/socket.c:2115
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2153
 __do_sys_sendmsg net/socket.c:2162 [inline]
 __se_sys_sendmsg net/socket.c:2160 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2160
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4401a9
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffd12dfb4f8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004401a9
RDX: 0000000000000000 RSI: 0000000020000280 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401a30
R13: 0000000000401ac0 R14: 0000000000000000 R15: 0000000000000000

The buggy address belongs to the variable:
 nft_immediate_policy+0x138/0x140

Memory state around the buggy address:
 ffffffff884fa980: 00 fa fa fa fa fa fa fa 00 00 00 00 00 00 fa fa
 ffffffff884faa00: fa fa fa fa 00 00 00 00 00 00 00 00 00 00 00 00
>ffffffff884faa80: 00 00 00 00 fa fa fa fa 04 fa fa fa fa fa fa fa
                                                                ^
 ffffffff884fab00: 00 00 00 00 00 00 00 00 00 00 00 00 00 fa fa fa
 ffffffff884fab80: fa fa fa fa 00 00 00 00 00 00 00 00 00 00 00 00
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