[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.162189][ T26] audit: type=1800 audit(1571760297.538:25): pid=7076 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.213150][ T26] audit: type=1800 audit(1571760297.538:26): pid=7076 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.247269][ T26] audit: type=1800 audit(1571760297.538:27): pid=7076 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 '10.128.1.22' (ECDSA) to the list of known hosts. 2019/10/22 16:05:05 fuzzer started 2019/10/22 16:05:06 dialing manager at 10.128.0.105:33369 2019/10/22 16:05:06 syscalls: 2524 2019/10/22 16:05:06 code coverage: enabled 2019/10/22 16:05:06 comparison tracing: enabled 2019/10/22 16:05:06 extra coverage: extra coverage is not supported by the kernel 2019/10/22 16:05:06 setuid sandbox: enabled 2019/10/22 16:05:06 namespace sandbox: enabled 2019/10/22 16:05:06 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 16:05:06 fault injection: enabled 2019/10/22 16:05:06 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 16:05:06 net packet injection: enabled 2019/10/22 16:05:06 net device setup: enabled 2019/10/22 16:05:06 concurrency sanitizer: enabled syzkaller login: [ 44.389517][ T7235] ================================================================== [ 44.397657][ T7235] BUG: KCSAN: data-race in tcp_add_backlog / tcp_recvmsg [ 44.404847][ T7235] [ 44.407338][ T7235] write to 0xffff888124a71338 of 8 bytes by interrupt on cpu 0: [ 44.414986][ T7235] tcp_add_backlog+0x45a/0xcc0 [ 44.419733][ T7235] tcp_v4_rcv+0x1a60/0x1bb0 [ 44.424215][ T7235] ip_protocol_deliver_rcu+0x4d/0x420 [ 44.429576][ T7235] ip_local_deliver_finish+0x110/0x140 [ 44.435031][ T7235] ip_local_deliver+0x133/0x210 [ 44.440471][ T7235] ip_rcv_finish+0x121/0x160 [ 44.445160][ T7235] ip_rcv+0x18f/0x1a0 [ 44.449125][ T7235] __netif_receive_skb_one_core+0xa7/0xe0 [ 44.454823][ T7235] __netif_receive_skb+0x37/0xf0 [ 44.459762][ T7235] netif_receive_skb_internal+0x59/0x190 [ 44.465460][ T7235] napi_gro_receive+0x28f/0x330 [ 44.470299][ T7235] receive_buf+0x284/0x30b0 [ 44.474780][ T7235] virtnet_poll+0x436/0x7d0 [ 44.479263][ T7235] net_rx_action+0x3ae/0xa90 [ 44.483840][ T7235] [ 44.486257][ T7235] read to 0xffff888124a71338 of 8 bytes by task 7235 on cpu 1: [ 44.494047][ T7235] tcp_recvmsg+0x470/0x1a30 [ 44.498530][ T7235] inet_recvmsg+0xbb/0x250 [ 44.502930][ T7235] sock_recvmsg+0x92/0xb0 [ 44.507242][ T7235] sock_read_iter+0x15f/0x1e0 [ 44.511910][ T7235] new_sync_read+0x389/0x4f0 [ 44.516479][ T7235] __vfs_read+0xb1/0xc0 [ 44.520661][ T7235] vfs_read+0x143/0x2c0 [ 44.524797][ T7235] ksys_read+0xd5/0x1b0 [ 44.528954][ T7235] __x64_sys_read+0x4c/0x60 [ 44.533456][ T7235] do_syscall_64+0xcc/0x370 [ 44.537946][ T7235] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 44.543816][ T7235] [ 44.546134][ T7235] Reported by Kernel Concurrency Sanitizer on: [ 44.552271][ T7235] CPU: 1 PID: 7235 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 44.559796][ T7235] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.569829][ T7235] ================================================================== [ 44.577870][ T7235] Kernel panic - not syncing: panic_on_warn set ... [ 44.584532][ T7235] CPU: 1 PID: 7235 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 44.593697][ T7235] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.603747][ T7235] Call Trace: [ 44.607033][ T7235] dump_stack+0xf5/0x159 [ 44.611255][ T7235] panic+0x210/0x640 [ 44.615144][ T7235] ? __x64_sys_read+0x4c/0x60 [ 44.619807][ T7235] ? vprintk_func+0x8d/0x140 [ 44.624398][ T7235] kcsan_report.cold+0xc/0x10 [ 44.629061][ T7235] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 44.634599][ T7235] __tsan_read8+0x2c/0x30 [ 44.638927][ T7235] tcp_recvmsg+0x470/0x1a30 [ 44.643417][ T7235] inet_recvmsg+0xbb/0x250 [ 44.647813][ T7235] ? __tsan_read8+0x2c/0x30 [ 44.652297][ T7235] ? inet_sendpage+0x100/0x100 [ 44.657057][ T7235] sock_recvmsg+0x92/0xb0 [ 44.661819][ T7235] sock_read_iter+0x15f/0x1e0 [ 44.666491][ T7235] new_sync_read+0x389/0x4f0 [ 44.671086][ T7235] __vfs_read+0xb1/0xc0 [ 44.675592][ T7235] vfs_read+0x143/0x2c0 [ 44.679741][ T7235] ksys_read+0xd5/0x1b0 [ 44.683892][ T7235] __x64_sys_read+0x4c/0x60 [ 44.688392][ T7235] do_syscall_64+0xcc/0x370 [ 44.692876][ T7235] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 44.698745][ T7235] RIP: 0033:0x47c530 [ 44.702621][ T7235] Code: 8b 7c 24 10 48 8b 74 24 18 48 8b 54 24 20 49 c7 c2 00 00 00 00 49 c7 c0 00 00 00 00 49 c7 c1 00 00 00 00 48 8b 44 24 08 0f 05 <48> 3d 01 f0 ff ff 76 20 48 c7 44 24 28 ff ff ff ff 48 c7 44 24 30 [ 44.722298][ T7235] RSP: 002b:000000c4204f57d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 44.730959][ T7235] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 44.738929][ T7235] RDX: 0000000000001000 RSI: 000000c42038a000 RDI: 0000000000000003 [ 44.748008][ T7235] RBP: 000000c4204f5830 R08: 0000000000000000 R09: 0000000000000000 [ 44.756002][ T7235] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000003 [ 44.764243][ T7235] R13: 000000c4200825b8 R14: 0000000000000002 R15: ffffffffffffffff [ 44.773823][ T7235] Kernel Offset: disabled [ 44.778271][ T7235] Rebooting in 86400 seconds..