syzbot


UBSAN: undefined-behaviour in nfnetlink_parse_nat_setup

Status: upstream: reported C repro on 2020/09/22 22:27
Reported-by: syzbot+b57803f38a8e54850be1@syzkaller.appspotmail.com
First crash: 1304d, last: 1290d
Fix bisection: failed (error log, bisect log)
  

Sample crash report:
audit: type=1400 audit(1600814504.737:8): avc:  denied  { execmem } for  pid=6501 comm="syz-executor839" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=process permissive=1
================================================================================
UBSAN: Undefined behaviour in net/netfilter/nf_nat_core.c:67:9
index 14 is out of range for type 'nf_nat_l3proto *[13]'
CPU: 0 PID: 6501 Comm: syz-executor839 Not tainted 4.19.146-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+0x22c/0x33e lib/dump_stack.c:118
 ubsan_epilogue+0xe/0x3a lib/ubsan.c:161
 __ubsan_handle_out_of_bounds.cold+0x63/0x6f lib/ubsan.c:383
 __nf_nat_l3proto_find net/netfilter/nf_nat_core.c:67 [inline]
 nfnetlink_parse_nat_setup+0x68c/0x750 net/netfilter/nf_nat_core.c:876
 ctnetlink_parse_nat_setup+0xd6/0x760 net/netfilter/nf_conntrack_netlink.c:1521
 ctnetlink_setup_nat net/netfilter/nf_conntrack_netlink.c:1591 [inline]
 ctnetlink_create_conntrack+0x48f/0x1350 net/netfilter/nf_conntrack_netlink.c:1984
 ctnetlink_new_conntrack+0x4f3/0xdb0 net/netfilter/nf_conntrack_netlink.c:2114
 nfnetlink_rcv_msg+0xeff/0x1210 net/netfilter/nfnetlink.c:233
 netlink_rcv_skb+0x160/0x440 net/netlink/af_netlink.c:2455
 nfnetlink_rcv+0x1b2/0x41b net/netfilter/nfnetlink.c:565
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x4d5/0x690 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x717/0xcc0 net/netlink/af_netlink.c:1909
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xc7/0x130 net/socket.c:632
 ___sys_sendmsg+0x7bb/0x8f0 net/socket.c:2115
 __sys_sendmsg net/socket.c:2153 [inline]
 __do_sys_sendmsg net/socket.c:2162 [inline]
 __se_sys_sendmsg net/socket.c:2160 [inline]
 __x64_sys_sendmsg+0x132/0x220 net/socket.c:2160
 do_syscall_64+0xf9/0x670 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x440679
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 7b 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffffdf6e7a8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440679
RDX: 0000000000000000 RSI: 0000000020000300 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 0000000000000001 R09: 00000000004002c8
R10: 0000000000000005 R11: 0000000000000246 R12: 0000000000401e80
R13: 0000000000401f10 R14: 0000000000000000 R15: 0000000000000000
================================================================================

Crashes (15):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/09/22 22:43 linux-4.19.y 015e94d0e37b 3e8f6c27 .config console log report syz C ci2-linux-4-19
2020/10/07 05:06 linux-4.19.y b09c34517e1a 1880b4a9 .config console log report info ci2-linux-4-19
2020/10/06 03:03 linux-4.19.y b09c34517e1a 1880b4a9 .config console log report info ci2-linux-4-19
2020/10/04 12:01 linux-4.19.y b09c34517e1a 5ef9c291 .config console log report info ci2-linux-4-19
2020/10/02 10:55 linux-4.19.y b09c34517e1a 9602ddf4 .config console log report info ci2-linux-4-19
2020/10/01 11:10 linux-4.19.y 10ad6cfd5736 4103fce0 .config console log report info ci2-linux-4-19
2020/09/30 06:06 linux-4.19.y 10ad6cfd5736 5abc3f1a .config console log report info ci2-linux-4-19
2020/09/30 02:17 linux-4.19.y 10ad6cfd5736 5abc3f1a .config console log report info ci2-linux-4-19
2020/09/27 16:04 linux-4.19.y 10ad6cfd5736 5dd8aee8 .config console log report info ci2-linux-4-19
2020/09/27 08:40 linux-4.19.y 10ad6cfd5736 5dd8aee8 .config console log report info ci2-linux-4-19
2020/09/27 06:26 linux-4.19.y 10ad6cfd5736 5dd8aee8 .config console log report info ci2-linux-4-19
2020/09/26 16:14 linux-4.19.y d09b80172c22 2d5ea0cb .config console log report info ci2-linux-4-19
2020/09/24 23:29 linux-4.19.y d09b80172c22 54289b08 .config console log report info ci2-linux-4-19
2020/09/23 17:54 linux-4.19.y d09b80172c22 287cd75a .config console log report info ci2-linux-4-19
2020/09/22 22:26 linux-4.19.y 015e94d0e37b 3e8f6c27 .config console log report info ci2-linux-4-19
* Struck through repros no longer work on HEAD.