bisecting fixing commit since 4fccc2503536a564a4ba31a1d50439854201659f building syzkaller on 2c36e7a75f8689b3da20e1a81a2ee5391f3af6e5 testing commit 4fccc2503536a564a4ba31a1d50439854201659f with gcc (GCC) 8.1.0 kernel signature: 65d17cd1efcc78f41be75362201836eeeee87b39b25bc975cfb56a3365049b77 all runs: crashed: kernel panic: audit: backlog limit exceeded testing current HEAD a834132bd465f9d7f4049be65648e01cf2533cb8 testing commit a834132bd465f9d7f4049be65648e01cf2533cb8 with gcc (GCC) 8.1.0 kernel signature: 771fb0592821738735cbc9453ae568dc46345f7ab7b9dc2b2d4f5576b9f04d74 all runs: crashed: kernel panic: audit: backlog limit exceeded revisions tested: 2, total time: 27m45.349667646s (build: 19m52.441658897s, test: 6m5.188573527s) the crash still happens on HEAD commit msg: Linux 4.19.140 crash: kernel panic: audit: backlog limit exceeded audit: type=1325 audit(1597968983.988:12): table=filter family=3 entries=0 audit: audit_backlog=14 > audit_backlog_limit=2 audit: type=1325 audit(1597968983.998:13): table=filter family=2 entries=0 audit: type=1325 audit(1597968983.998:14): table=nat family=2 entries=0 audit: audit_lost=1 audit_rate_limit=4294967295 audit_backlog_limit=2 Kernel panic - not syncing: audit: backlog limit exceeded CPU: 0 PID: 6561 Comm: syz-executor.2 Not tainted 4.19.140-syzkaller #0 audit: type=1325 audit(1597968983.998:15): table=mangle family=2 entries=0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: audit: type=1325 audit(1597968983.998:16): table=raw family=2 entries=0 __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: type=1325 audit(1597968983.998:17): table=security family=2 entries=0 audit_panic.cold.22+0x28/0x28 kernel/audit.c:320 audit_log_lost+0x57/0x120 kernel/audit.c:390 audit_log_start+0x2e7/0x680 kernel/audit.c:1800 audit_log+0x73/0xf0 kernel/audit.c:2391 audit: type=1325 audit(1597968983.998:18): table=filter family=10 entries=0 xt_replace_table+0x555/0x750 net/netfilter/x_tables.c:1418 xt_register_table+0x253/0x52c net/netfilter/x_tables.c:1457 arpt_register_table+0x188/0x2c0 net/ipv4/netfilter/arp_tables.c:1558 arptable_filter_table_init.part.0+0x3f/0x60 net/ipv4/netfilter/arptable_filter.c:52 arptable_filter_table_init+0x3d/0x50 net/ipv4/netfilter/arptable_filter.c:56 xt_find_table_lock+0x206/0x370 net/netfilter/x_tables.c:1228 xt_request_find_table_lock+0x1c/0xa0 net/netfilter/x_tables.c:1258 get_info+0x10b/0x470 net/ipv6/netfilter/ip6_tables.c:984 do_arpt_get_ctl+0x2fd/0x630 net/ipv4/netfilter/arp_tables.c:1484 nf_sockopt net/netfilter/nf_sockopt.c:104 [inline] nf_getsockopt+0x5f/0xc0 net/netfilter/nf_sockopt.c:122 ip_getsockopt+0xf9/0x130 net/ipv4/ip_sockglue.c:1574 tcp_getsockopt+0x6a/0xd0 net/ipv4/tcp.c:3616 sock_common_getsockopt+0x73/0xf0 net/core/sock.c:3010 __sys_getsockopt+0x12e/0x1f0 net/socket.c:1938 __do_sys_getsockopt net/socket.c:1949 [inline] __se_sys_getsockopt net/socket.c:1946 [inline] __x64_sys_getsockopt+0xb9/0x150 net/socket.c:1946 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45efba Code: b8 34 01 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 0d 8b fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 49 89 ca b8 37 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 ea 8a fb ff c3 66 0f 1f 84 00 00 00 00 00 RSP: 002b:00007ffe1f23ff68 EFLAGS: 00000246 ORIG_RAX: 0000000000000037 RAX: ffffffffffffffda RBX: 00000000004cd165 RCX: 000000000045efba RDX: 0000000000000060 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000003 R08: 00007ffe1f23ff7c R09: 0000000000000004 R10: 000000000071b468 R11: 0000000000000246 R12: 000000000071ade8 R13: 00007ffe1f240600 R14: 0000000000000003 R15: 00007ffe1f240610 Kernel Offset: disabled Rebooting in 86400 seconds..