[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.088564][ T26] audit: type=1800 audit(1571680400.504:25): pid=7006 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.116232][ T26] audit: type=1800 audit(1571680400.504:26): pid=7006 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.158778][ T26] audit: type=1800 audit(1571680400.504:27): pid=7006 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2469 res=0 [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.98' (ECDSA) to the list of known hosts. 2019/10/21 17:53:30 fuzzer started 2019/10/21 17:53:32 dialing manager at 10.128.0.105:39747 2019/10/21 17:53:32 syscalls: 2524 2019/10/21 17:53:32 code coverage: enabled 2019/10/21 17:53:32 comparison tracing: enabled 2019/10/21 17:53:32 extra coverage: extra coverage is not supported by the kernel 2019/10/21 17:53:32 setuid sandbox: enabled 2019/10/21 17:53:32 namespace sandbox: enabled 2019/10/21 17:53:32 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/21 17:53:32 fault injection: enabled 2019/10/21 17:53:32 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/21 17:53:32 net packet injection: enabled 2019/10/21 17:53:32 net device setup: enabled 2019/10/21 17:53:32 concurrency sanitizer: enabled syzkaller login: [ 47.227225][ T7168] ================================================================== [ 47.235361][ T7168] BUG: KCSAN: data-race in tcp_poll / tcp_queue_rcv [ 47.241957][ T7168] [ 47.244374][ T7168] write to 0xffff888124179778 of 4 bytes by interrupt on cpu 1: [ 47.252013][ T7168] tcp_queue_rcv+0x338/0x380 [ 47.256953][ T7168] tcp_rcv_established+0xbf1/0xf50 [ 47.262142][ T7168] tcp_v4_do_rcv+0x381/0x4e0 [ 47.266731][ T7168] tcp_v4_rcv+0x19dc/0x1bb0 [ 47.271252][ T7168] ip_protocol_deliver_rcu+0x4d/0x420 [ 47.276625][ T7168] ip_local_deliver_finish+0x110/0x140 [ 47.282067][ T7168] ip_local_deliver+0x133/0x210 [ 47.286917][ T7168] ip_rcv_finish+0x121/0x160 [ 47.291492][ T7168] ip_rcv+0x18f/0x1a0 [ 47.295471][ T7168] __netif_receive_skb_one_core+0xa7/0xe0 [ 47.301189][ T7168] __netif_receive_skb+0x37/0xf0 [ 47.306111][ T7168] netif_receive_skb_internal+0x59/0x190 [ 47.311742][ T7168] napi_gro_receive+0x28f/0x330 [ 47.316593][ T7168] receive_buf+0x284/0x30b0 [ 47.321071][ T7168] [ 47.323390][ T7168] read to 0xffff888124179778 of 4 bytes by task 7168 on cpu 0: [ 47.331003][ T7168] tcp_poll+0x204/0x6b0 [ 47.335146][ T7168] sock_poll+0xed/0x250 [ 47.339289][ T7168] ep_item_poll.isra.0+0x90/0x190 [ 47.344384][ T7168] ep_send_events_proc+0x113/0x590 [ 47.349495][ T7168] ep_scan_ready_list.constprop.0+0x189/0x500 [ 47.355562][ T7168] ep_poll+0xe3/0x900 [ 47.359531][ T7168] do_epoll_wait+0x162/0x180 [ 47.364110][ T7168] __x64_sys_epoll_pwait+0xcd/0x180 [ 47.369471][ T7168] do_syscall_64+0xcc/0x370 [ 47.373961][ T7168] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 47.379828][ T7168] [ 47.382139][ T7168] Reported by Kernel Concurrency Sanitizer on: [ 47.388303][ T7168] CPU: 0 PID: 7168 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 47.395739][ T7168] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 47.405783][ T7168] ================================================================== [ 47.413849][ T7168] Kernel panic - not syncing: panic_on_warn set ... [ 47.421118][ T7168] CPU: 0 PID: 7168 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 47.428727][ T7168] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 47.438778][ T7168] Call Trace: [ 47.442059][ T7168] dump_stack+0xf5/0x159 [ 47.446288][ T7168] panic+0x210/0x640 [ 47.450174][ T7168] ? do_syscall_64+0xcc/0x370 [ 47.454837][ T7168] ? vprintk_func+0x8d/0x140 [ 47.459556][ T7168] kcsan_report.cold+0xc/0x10 [ 47.464223][ T7168] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 47.469759][ T7168] __tsan_read4+0x2c/0x30 [ 47.474079][ T7168] tcp_poll+0x204/0x6b0 [ 47.478229][ T7168] ? tcp_alloc_md5sig_pool+0x320/0x320 [ 47.489078][ T7168] sock_poll+0xed/0x250 [ 47.493224][ T7168] ? sock_read_iter+0x1e0/0x1e0 [ 47.498260][ T7168] ep_item_poll.isra.0+0x90/0x190 [ 47.503274][ T7168] ep_send_events_proc+0x113/0x590 [ 47.508373][ T7168] ? __schedule+0x319/0x640 [ 47.512864][ T7168] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 47.519187][ T7168] ep_scan_ready_list.constprop.0+0x189/0x500 [ 47.525330][ T7168] ? ep_loop_check_proc+0x2f0/0x2f0 [ 47.531064][ T7168] ep_poll+0xe3/0x900 [ 47.535058][ T7168] ? wake_up_q+0x70/0x70 [ 47.539659][ T7168] do_epoll_wait+0x162/0x180 [ 47.544246][ T7168] __x64_sys_epoll_pwait+0xcd/0x180 [ 47.549438][ T7168] do_syscall_64+0xcc/0x370 [ 47.553933][ T7168] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 47.559809][ T7168] RIP: 0033:0x45b300 [ 47.563705][ T7168] Code: 0f 05 89 44 24 20 c3 cc cc cc 8b 7c 24 08 48 8b 74 24 10 8b 54 24 18 44 8b 54 24 1c 49 c7 c0 00 00 00 00 b8 19 01 00 00 0f 05 <89> 44 24 20 c3 cc cc cc cc cc cc cc cc cc cc cc 8b 7c 24 08 48 c7 [ 47.583380][ T7168] RSP: 002b:000000c420149860 EFLAGS: 00000246 ORIG_RAX: 0000000000000119 [ 47.591799][ T7168] RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 000000000045b300 [ 47.599779][ T7168] RDX: 0000000000000080 RSI: 000000c4201498a0 RDI: 0000000000000004 [ 47.607858][ T7168] RBP: 000000c420149ea0 R08: 0000000000000000 R09: 000000c420001c80 [ 47.615819][ T7168] R10: 00000000ffffffff R11: 0000000000000246 R12: 0000000000000280 [ 47.623778][ T7168] R13: 00000000000000ff R14: 00007f893e037000 R15: 0000000000000020 [ 47.633209][ T7168] Kernel Offset: disabled [ 47.637530][ T7168] Rebooting in 86400 seconds..