[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.834278][ T25] audit: type=1800 audit(1571734620.440:25): pid=7031 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.864929][ T25] audit: type=1800 audit(1571734620.450:26): pid=7031 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.888077][ T25] audit: type=1800 audit(1571734620.450:27): pid=7031 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 '10.128.0.31' (ECDSA) to the list of known hosts. 2019/10/22 08:57:10 fuzzer started 2019/10/22 08:57:13 dialing manager at 10.128.0.105:37053 2019/10/22 08:57:13 syscalls: 2524 2019/10/22 08:57:13 code coverage: enabled 2019/10/22 08:57:13 comparison tracing: enabled 2019/10/22 08:57:13 extra coverage: extra coverage is not supported by the kernel 2019/10/22 08:57:13 setuid sandbox: enabled 2019/10/22 08:57:13 namespace sandbox: enabled 2019/10/22 08:57:13 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 08:57:13 fault injection: enabled 2019/10/22 08:57:13 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 08:57:13 net packet injection: enabled 2019/10/22 08:57:13 net device setup: enabled 2019/10/22 08:57:13 concurrency sanitizer: enabled syzkaller login: [ 48.460561][ T7189] ================================================================== [ 48.468663][ T7189] BUG: KCSAN: data-race in tcp_poll / tcp_queue_rcv [ 48.475656][ T7189] [ 48.477983][ T7189] write to 0xffff8881220485b8 of 4 bytes by interrupt on cpu 1: [ 48.485603][ T7189] tcp_queue_rcv+0xe9/0x380 [ 48.490088][ T7189] tcp_data_queue+0x7bb/0x20b0 [ 48.494840][ T7189] tcp_rcv_established+0x517/0xf50 [ 48.499943][ T7189] tcp_v4_do_rcv+0x381/0x4e0 [ 48.504511][ T7189] tcp_v4_rcv+0x19dc/0x1bb0 [ 48.508992][ T7189] ip_protocol_deliver_rcu+0x4d/0x420 [ 48.514355][ T7189] ip_local_deliver_finish+0x110/0x140 [ 48.519791][ T7189] ip_local_deliver+0x133/0x210 [ 48.524624][ T7189] ip_rcv_finish+0x121/0x160 [ 48.529197][ T7189] ip_rcv+0x18f/0x1a0 [ 48.533161][ T7189] __netif_receive_skb_one_core+0xa7/0xe0 [ 48.538854][ T7189] __netif_receive_skb+0x37/0xf0 [ 48.543765][ T7189] netif_receive_skb_internal+0x59/0x190 [ 48.549382][ T7189] napi_gro_receive+0x28f/0x330 [ 48.554205][ T7189] [ 48.556515][ T7189] read to 0xffff8881220485b8 of 4 bytes by task 7189 on cpu 0: [ 48.564040][ T7189] tcp_poll+0x204/0x6b0 [ 48.568185][ T7189] sock_poll+0xed/0x250 [ 48.572319][ T7189] ep_item_poll.isra.0+0x90/0x190 [ 48.577327][ T7189] ep_send_events_proc+0x113/0x590 [ 48.582415][ T7189] ep_scan_ready_list.constprop.0+0x189/0x500 [ 48.588459][ T7189] ep_poll+0xe3/0x900 [ 48.592445][ T7189] do_epoll_wait+0x162/0x180 [ 48.597012][ T7189] __x64_sys_epoll_pwait+0xcd/0x180 [ 48.602189][ T7189] do_syscall_64+0xcc/0x370 [ 48.606671][ T7189] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.612536][ T7189] [ 48.614862][ T7189] Reported by Kernel Concurrency Sanitizer on: [ 48.620994][ T7189] CPU: 0 PID: 7189 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 48.628426][ T7189] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.638456][ T7189] ================================================================== [ 48.646489][ T7189] Kernel panic - not syncing: panic_on_warn set ... [ 48.653050][ T7189] CPU: 0 PID: 7189 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 48.660483][ T7189] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.670525][ T7189] Call Trace: [ 48.673794][ T7189] dump_stack+0xf5/0x159 [ 48.678013][ T7189] panic+0x210/0x640 [ 48.681974][ T7189] ? do_syscall_64+0xcc/0x370 [ 48.686627][ T7189] ? vprintk_func+0x8d/0x140 [ 48.691196][ T7189] kcsan_report.cold+0xc/0x10 [ 48.695855][ T7189] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 48.701376][ T7189] __tsan_read4+0x2c/0x30 [ 48.705703][ T7189] tcp_poll+0x204/0x6b0 [ 48.709844][ T7189] ? tcp_alloc_md5sig_pool+0x320/0x320 [ 48.715283][ T7189] sock_poll+0xed/0x250 [ 48.719416][ T7189] ? sock_read_iter+0x1e0/0x1e0 [ 48.724250][ T7189] ep_item_poll.isra.0+0x90/0x190 [ 48.729270][ T7189] ep_send_events_proc+0x113/0x590 [ 48.734369][ T7189] ? __schedule+0x319/0x640 [ 48.738860][ T7189] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 48.744477][ T7189] ep_scan_ready_list.constprop.0+0x189/0x500 [ 48.750527][ T7189] ? ep_loop_check_proc+0x2f0/0x2f0 [ 48.755702][ T7189] ep_poll+0xe3/0x900 [ 48.759709][ T7189] ? wake_up_q+0x70/0x70 [ 48.763929][ T7189] do_epoll_wait+0x162/0x180 [ 48.768498][ T7189] __x64_sys_epoll_pwait+0xcd/0x180 [ 48.773674][ T7189] do_syscall_64+0xcc/0x370 [ 48.778418][ T7189] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.784283][ T7189] RIP: 0033:0x45b300 [ 48.788165][ T7189] 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 [ 48.807772][ T7189] RSP: 002b:000000c4201bb860 EFLAGS: 00000246 ORIG_RAX: 0000000000000119 [ 48.816158][ T7189] RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 000000000045b300 [ 48.824127][ T7189] RDX: 0000000000000080 RSI: 000000c4201bb8a0 RDI: 0000000000000004 [ 48.832074][ T7189] RBP: 000000c4201bbea0 R08: 0000000000000000 R09: 000000c420001200 [ 48.840029][ T7189] R10: 00000000ffffffff R11: 0000000000000246 R12: 000000c4200c5b00 [ 48.847978][ T7189] R13: 0000000000000007 R14: 0000000000c14060 R15: ffffffffffffffff [ 48.857078][ T7189] Kernel Offset: disabled [ 48.861396][ T7189] Rebooting in 86400 seconds..