bisecting fixing commit since 4fccc2503536a564a4ba31a1d50439854201659f building syzkaller on 2c36e7a75f8689b3da20e1a81a2ee5391f3af6e5 testing commit 4fccc2503536a564a4ba31a1d50439854201659f with gcc (GCC) 8.1.0 kernel signature: c0ba286ca42b5d130dd8cf78d95b4c00d41b7454e7b69fe296bc335cc8849c40 all runs: crashed: kernel panic: audit: backlog limit exceeded testing current HEAD 14cfdbd39e316efd91ae6e403ef8211f0b022603 testing commit 14cfdbd39e316efd91ae6e403ef8211f0b022603 with gcc (GCC) 8.1.0 kernel signature: 01f4cf405fa24e0fddec3394e2f76386dbd1474a75b6e2857e0b72338d18fe7a all runs: crashed: kernel panic: audit: backlog limit exceeded revisions tested: 2, total time: 28m19.436690251s (build: 19m9.45478575s, test: 8m1.343237216s) the crash still happens on HEAD commit msg: Linux 4.19.112 crash: kernel panic: audit: backlog limit exceeded audit: type=1305 audit(1585000010.942:45): audit_pid=0 old=0 auid=4294967295 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 res=1 audit: audit_lost=1 audit_rate_limit=4294967295 audit_backlog_limit=2 audit: audit_lost=2 audit_rate_limit=4294967295 audit_backlog_limit=2 audit: type=1305 audit(1585000010.942:46): audit_rate_limit=4294967295 old=0 auid=4294967295 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 res=1 Kernel panic - not syncing: audit: backlog limit exceeded CPU: 1 PID: 7468 Comm: syz-executor.4 Not tainted 4.19.112-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 audit: type=1305 audit(1585000010.942:47): audit_backlog_limit=2 old=64 auid=4294967295 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 res=1 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x123/0x177 lib/dump_stack.c:118 panic+0x1cd/0x375 kernel/panic.c:186 audit_panic.cold.22+0x28/0x28 kernel/audit.c:320 audit: type=1305 audit(1585000010.942:48): audit_backlog_wait_time=0 old=6000 auid=4294967295 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 res=1 audit_log_lost+0x57/0x120 kernel/audit.c:390 audit_log_start+0x2e7/0x680 kernel/audit.c:1789 audit_log+0x73/0xf0 kernel/audit.c:2380 xt_replace_table+0x555/0x750 net/netfilter/x_tables.c:1418 __do_replace+0x1a9/0x9b0 net/ipv6/netfilter/ip6_tables.c:1087 do_replace net/ipv6/netfilter/ip6_tables.c:1160 [inline] do_ip6t_set_ctl+0x27e/0x3eb net/ipv6/netfilter/ip6_tables.c:1684 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline] nf_setsockopt+0x5c/0xb0 net/netfilter/nf_sockopt.c:115 ipv6_setsockopt+0x95/0xf0 net/ipv6/ipv6_sockglue.c:944 tcp_setsockopt+0x6a/0xd0 net/ipv4/tcp.c:3082 sock_common_setsockopt+0x73/0xf0 net/core/sock.c:3049 __sys_setsockopt+0x13e/0x210 net/socket.c:1901 __do_sys_setsockopt net/socket.c:1912 [inline] __se_sys_setsockopt net/socket.c:1909 [inline] __x64_sys_setsockopt+0xb9/0x150 net/socket.c:1909 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45ef5a Code: 49 89 ca b8 37 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 6a 8b fb ff c3 66 0f 1f 84 00 00 00 00 00 49 89 ca b8 36 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 4a 8b fb ff c3 66 0f 1f 84 00 00 00 00 00 RSP: 002b:00007ffea5e09418 EFLAGS: 00000206 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00007ffea5e09440 RCX: 000000000045ef5a RDX: 0000000000000040 RSI: 0000000000000029 RDI: 0000000000000003 RBP: 000000000071dcc0 R08: 0000000000000558 R09: 0000000000004000 R10: 000000000071c8e0 R11: 0000000000000206 R12: 0000000000000003 R13: 0000000000000000 R14: 0000000000000029 R15: 000000000071c880 Shutting down cpus with NMI Kernel Offset: disabled Rebooting in 86400 seconds..