bisecting fixing commit since 98db2bf27b9ed2d5ed0b6c9c8a4bfcb127a19796
building syzkaller on 1253d6f07f7f40d2835e0d1e061dcbad49ae28ee
testing commit 98db2bf27b9ed2d5ed0b6c9c8a4bfcb127a19796 with gcc (GCC) 8.1.0
kernel signature: cd9986af565101071cf7d2617cab2ad4ff3b1832cfe43f7d389115ccac743447
all runs: crashed: kernel panic: audit: backlog limit exceeded
testing current HEAD 050272a0423e68207fd2367831ae610680129062
testing commit 050272a0423e68207fd2367831ae610680129062 with gcc (GCC) 8.1.0
kernel signature: 9a071901dcf82eff695b3ef4ca76e2dd9f1d967984a125ff9edb20644bc01c04
all runs: crashed: kernel panic: audit: backlog limit exceeded
revisions tested: 2, total time: 24m37.766442357s (build: 17m10.883760798s, test: 6m30.533948807s)
the crash still happens on HEAD
commit msg: Linux 4.14.177
crash: kernel panic: audit: backlog limit exceeded
audit: audit_backlog=3 > audit_backlog_limit=2
audit: audit_lost=1 audit_rate_limit=4294967295 audit_backlog_limit=2
IPv6: ADDRCONF(NETDEV_CHANGE): veth0_vlan: link becomes ready
audit: audit_backlog=3 > audit_backlog_limit=2
audit: audit_lost=2 audit_rate_limit=4294967295 audit_backlog_limit=2
Kernel panic - not syncing: audit: backlog limit exceeded

CPU: 1 PID: 6450 Comm: syz-executor.3 Not tainted 4.14.177-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xf7/0x13b lib/dump_stack.c:58
 panic+0x1b0/0x358 kernel/panic.c:183
 audit_panic.cold.22+0x28/0x28 kernel/audit.c:280
 audit_log_lost+0x42/0xd0 kernel/audit.c:350
 audit_log_start+0x2c5/0x630 kernel/audit.c:1736
 audit_log+0x6a/0xd0 kernel/audit.c:2338
 xt_replace_table+0x402/0x5d0 net/netfilter/x_tables.c:1266
 __do_replace+0x175/0x5d0 net/ipv4/netfilter/ip_tables.c:1069
 do_replace net/ipv4/netfilter/ip_tables.c:1142 [inline]
 do_ipt_set_ctl+0x25c/0x3be net/ipv4/netfilter/ip_tables.c:1674
 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline]
 nf_setsockopt+0x5c/0xb0 net/netfilter/nf_sockopt.c:115
 ip_setsockopt+0x59/0x70 net/ipv4/ip_sockglue.c:1255
 tcp_setsockopt+0x6a/0xd0 net/ipv4/tcp.c:2826
 sock_common_setsockopt+0x73/0xf0 net/core/sock.c:2971
 SYSC_setsockopt net/socket.c:1865 [inline]
 SyS_setsockopt+0x130/0x1f0 net/socket.c:1844
 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45ef5a
RSP: 002b:00007ffd2ff310b8 EFLAGS: 00000206 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007ffd2ff310e0 RCX: 000000000045ef5a
RDX: 0000000000000040 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 000000000071fe80 R08: 00000000000002d8 R09: 0000000000004000
R10: 000000000071dd20 R11: 0000000000000206 R12: 0000000000000003
R13: 0000000000000000 R14: 0000000000000000 R15: 000000000071dcc0
Shutting down cpus with NMI
Kernel Offset: disabled
Rebooting in 86400 seconds..