[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 42.341089][ T25] audit: type=1800 audit(1571726202.235:25): pid=7059 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 42.360689][ T25] audit: type=1800 audit(1571726202.235:26): pid=7059 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 42.360705][ T25] audit: type=1800 audit(1571726202.235:27): pid=7059 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 '10.128.10.9' (ECDSA) to the list of known hosts. 2019/10/22 06:36:50 fuzzer started 2019/10/22 06:36:52 dialing manager at 10.128.0.105:37053 2019/10/22 06:36:52 syscalls: 2524 2019/10/22 06:36:52 code coverage: enabled 2019/10/22 06:36:52 comparison tracing: enabled 2019/10/22 06:36:52 extra coverage: extra coverage is not supported by the kernel 2019/10/22 06:36:52 setuid sandbox: enabled 2019/10/22 06:36:52 namespace sandbox: enabled 2019/10/22 06:36:52 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 06:36:52 fault injection: enabled 2019/10/22 06:36:52 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 06:36:52 net packet injection: enabled 2019/10/22 06:36:52 net device setup: enabled 2019/10/22 06:36:52 concurrency sanitizer: enabled syzkaller login: [ 52.527556][ T7215] ================================================================== [ 52.535671][ T7215] BUG: KCSAN: data-race in tcp_poll / tcp_queue_rcv [ 52.542226][ T7215] [ 52.544533][ T7215] write to 0xffff8881265ae5b8 of 4 bytes by interrupt on cpu 0: [ 52.552183][ T7215] tcp_queue_rcv+0xe9/0x380 [ 52.556661][ T7215] tcp_rcv_established+0xbf1/0xf50 [ 52.561747][ T7215] tcp_v4_do_rcv+0x381/0x4e0 [ 52.566321][ T7215] tcp_v4_rcv+0x19dc/0x1bb0 [ 52.570796][ T7215] ip_protocol_deliver_rcu+0x4d/0x420 [ 52.576143][ T7215] ip_local_deliver_finish+0x110/0x140 [ 52.581688][ T7215] ip_local_deliver+0x133/0x210 [ 52.586512][ T7215] ip_rcv_finish+0x121/0x160 [ 52.591074][ T7215] ip_rcv+0x18f/0x1a0 [ 52.595048][ T7215] __netif_receive_skb_one_core+0xa7/0xe0 [ 52.600831][ T7215] __netif_receive_skb+0x37/0xf0 [ 52.605747][ T7215] netif_receive_skb_internal+0x59/0x190 [ 52.611441][ T7215] napi_gro_receive+0x28f/0x330 [ 52.616267][ T7215] receive_buf+0x284/0x30b0 [ 52.620748][ T7215] [ 52.623054][ T7215] read to 0xffff8881265ae5b8 of 4 bytes by task 7215 on cpu 1: [ 52.630577][ T7215] tcp_poll+0x204/0x6b0 [ 52.634713][ T7215] sock_poll+0xed/0x250 [ 52.638849][ T7215] ep_item_poll.isra.0+0x90/0x190 [ 52.643866][ T7215] ep_send_events_proc+0x113/0x590 [ 52.648971][ T7215] ep_scan_ready_list.constprop.0+0x189/0x500 [ 52.655013][ T7215] ep_poll+0xe3/0x900 [ 52.659135][ T7215] do_epoll_wait+0x162/0x180 [ 52.663719][ T7215] __x64_sys_epoll_pwait+0xcd/0x180 [ 52.668991][ T7215] do_syscall_64+0xcc/0x370 [ 52.673471][ T7215] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 52.679339][ T7215] [ 52.681642][ T7215] Reported by Kernel Concurrency Sanitizer on: [ 52.687771][ T7215] CPU: 1 PID: 7215 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 52.695201][ T7215] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 52.705230][ T7215] ================================================================== [ 52.713264][ T7215] Kernel panic - not syncing: panic_on_warn set ... [ 52.719839][ T7215] CPU: 1 PID: 7215 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 52.727274][ T7215] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 52.737309][ T7215] Call Trace: [ 52.740592][ T7215] dump_stack+0xf5/0x159 [ 52.744813][ T7215] panic+0x210/0x640 [ 52.748690][ T7215] ? do_syscall_64+0xcc/0x370 [ 52.753433][ T7215] ? vprintk_func+0x8d/0x140 [ 52.758001][ T7215] kcsan_report.cold+0xc/0x10 [ 52.762666][ T7215] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 52.768188][ T7215] __tsan_read4+0x2c/0x30 [ 52.772495][ T7215] tcp_poll+0x204/0x6b0 [ 52.776639][ T7215] ? tcp_alloc_md5sig_pool+0x320/0x320 [ 52.782169][ T7215] sock_poll+0xed/0x250 [ 52.786306][ T7215] ? sock_read_iter+0x1e0/0x1e0 [ 52.791133][ T7215] ep_item_poll.isra.0+0x90/0x190 [ 52.796140][ T7215] ep_send_events_proc+0x113/0x590 [ 52.801237][ T7215] ? __schedule+0x319/0x640 [ 52.805715][ T7215] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 52.811329][ T7215] ep_scan_ready_list.constprop.0+0x189/0x500 [ 52.817383][ T7215] ? ep_loop_check_proc+0x2f0/0x2f0 [ 52.822574][ T7215] ep_poll+0xe3/0x900 [ 52.826626][ T7215] ? wake_up_q+0x70/0x70 [ 52.830868][ T7215] do_epoll_wait+0x162/0x180 [ 52.835451][ T7215] __x64_sys_epoll_pwait+0xcd/0x180 [ 52.840631][ T7215] do_syscall_64+0xcc/0x370 [ 52.845148][ T7215] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 52.851035][ T7215] RIP: 0033:0x45b300 [ 52.854913][ T7215] 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 [ 52.874492][ T7215] RSP: 002b:000000c420151860 EFLAGS: 00000246 ORIG_RAX: 0000000000000119 [ 52.882878][ T7215] RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 000000000045b300 [ 52.890823][ T7215] RDX: 0000000000000080 RSI: 000000c4201518a0 RDI: 0000000000000004 [ 52.898771][ T7215] RBP: 000000c420151ea0 R08: 0000000000000000 R09: 0000000000000000 [ 52.906719][ T7215] R10: 00000000ffffffff R11: 0000000000000246 R12: 00000000000000d4 [ 52.914666][ T7215] R13: 00000000000000d3 R14: 0000000000000200 R15: ffffffffffffffff [ 52.923985][ T7215] Kernel Offset: disabled [ 52.928302][ T7215] Rebooting in 86400 seconds..