[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [ 54.939403][ T26] kauditd_printk_skb: 8 callbacks suppressed [ 54.939418][ T26] audit: type=1800 audit(1575148149.966:29): pid=7439 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rc.local" dev="sda1" ino=2465 res=0 [ 54.970253][ T26] audit: type=1800 audit(1575148149.966:30): pid=7439 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rmnologin" dev="sda1" ino=2456 res=0 Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.10.0' (ECDSA) to the list of known hosts. 2019/11/30 21:09:17 fuzzer started 2019/11/30 21:09:18 dialing manager at 10.128.0.105:36521 2019/11/30 21:09:18 syscalls: 2592 2019/11/30 21:09:18 code coverage: enabled 2019/11/30 21:09:18 comparison tracing: enabled 2019/11/30 21:09:18 extra coverage: extra coverage is not supported by the kernel 2019/11/30 21:09:18 setuid sandbox: enabled 2019/11/30 21:09:18 namespace sandbox: enabled 2019/11/30 21:09:18 Android sandbox: /sys/fs/selinux/policy does not exist 2019/11/30 21:09:18 fault injection: enabled 2019/11/30 21:09:18 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/11/30 21:09:18 net packet injection: enabled 2019/11/30 21:09:18 net device setup: enabled 2019/11/30 21:09:18 concurrency sanitizer: enabled 2019/11/30 21:09:18 devlink PCI setup: PCI device 0000:00:10.0 is not available 2019/11/30 21:09:18 adding functions to KCSAN blacklist: 'pipe_poll' '__hrtimer_run_queues' syzkaller login: [ 63.985272][ T7588] ================================================================== [ 63.993415][ T7588] BUG: KCSAN: data-race in tcp_add_backlog / tcp_recvmsg [ 64.000440][ T7588] [ 64.002765][ T7588] write to 0xffff8881252f9338 of 8 bytes by interrupt on cpu 0: [ 64.010754][ T7588] tcp_add_backlog+0x476/0xce0 [ 64.015677][ T7588] tcp_v4_rcv+0x1a70/0x1bd0 [ 64.020248][ T7588] ip_protocol_deliver_rcu+0x4d/0x420 [ 64.025718][ T7588] ip_local_deliver_finish+0x110/0x140 [ 64.031169][ T7588] ip_local_deliver+0x133/0x210 [ 64.036025][ T7588] ip_rcv_finish+0x121/0x160 [ 64.040615][ T7588] ip_rcv+0x18f/0x1a0 [ 64.044672][ T7588] __netif_receive_skb_one_core+0xa7/0xe0 [ 64.050465][ T7588] __netif_receive_skb+0x37/0xf0 [ 64.055579][ T7588] netif_receive_skb_internal+0x59/0x190 [ 64.061559][ T7588] napi_gro_receive+0x28f/0x330 [ 64.067145][ T7588] receive_buf+0x284/0x30b0 [ 64.071666][ T7588] virtnet_poll+0x436/0x7d0 [ 64.076280][ T7588] net_rx_action+0x3ae/0xa90 [ 64.081213][ T7588] __do_softirq+0x115/0x33f [ 64.085975][ T7588] irq_exit+0xbb/0xe0 [ 64.090147][ T7588] do_IRQ+0x81/0x130 [ 64.094161][ T7588] ret_from_intr+0x0/0x19 [ 64.098499][ T7588] native_safe_halt+0xe/0x10 [ 64.103358][ T7588] arch_cpu_idle+0xa/0x10 [ 64.107690][ T7588] default_idle_call+0x1e/0x40 [ 64.112584][ T7588] do_idle+0x1af/0x280 [ 64.116665][ T7588] cpu_startup_entry+0x1b/0x20 [ 64.121444][ T7588] rest_init+0xec/0xf6 [ 64.125669][ T7588] arch_call_rest_init+0x17/0x37 [ 64.130598][ T7588] start_kernel+0x838/0x85e [ 64.135098][ T7588] x86_64_start_reservations+0x29/0x2b [ 64.140565][ T7588] x86_64_start_kernel+0x72/0x76 [ 64.145622][ T7588] secondary_startup_64+0xa4/0xb0 [ 64.150830][ T7588] [ 64.153186][ T7588] read to 0xffff8881252f9338 of 8 bytes by task 7588 on cpu 1: [ 64.160735][ T7588] tcp_recvmsg+0x46e/0x1b40 [ 64.165232][ T7588] inet_recvmsg+0xbb/0x250 [ 64.169682][ T7588] sock_recvmsg+0x92/0xb0 [ 64.174010][ T7588] sock_read_iter+0x15f/0x1e0 [ 64.178710][ T7588] new_sync_read+0x389/0x4f0 [ 64.183298][ T7588] __vfs_read+0xb1/0xc0 [ 64.187537][ T7588] vfs_read+0x143/0x2c0 [ 64.191687][ T7588] ksys_read+0xd5/0x1b0 [ 64.195849][ T7588] __x64_sys_read+0x4c/0x60 [ 64.200359][ T7588] do_syscall_64+0xcc/0x370 [ 64.204880][ T7588] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 64.210874][ T7588] [ 64.213309][ T7588] Reported by Kernel Concurrency Sanitizer on: [ 64.219472][ T7588] CPU: 1 PID: 7588 Comm: syz-fuzzer Not tainted 5.4.0-syzkaller #0 [ 64.227356][ T7588] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 64.237408][ T7588] ================================================================== [ 64.245478][ T7588] Kernel panic - not syncing: panic_on_warn set ... [ 64.252084][ T7588] CPU: 1 PID: 7588 Comm: syz-fuzzer Not tainted 5.4.0-syzkaller #0 [ 64.260053][ T7588] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 64.270217][ T7588] Call Trace: [ 64.273510][ T7588] dump_stack+0x11d/0x181 [ 64.277842][ T7588] panic+0x210/0x640 [ 64.281909][ T7588] ? vprintk_func+0x8d/0x140 [ 64.286485][ T7588] kcsan_report.cold+0xc/0xd [ 64.291064][ T7588] kcsan_setup_watchpoint+0x3fe/0x460 [ 64.296436][ T7588] __tsan_read8+0xc6/0x100 [ 64.300835][ T7588] tcp_recvmsg+0x46e/0x1b40 [ 64.305345][ T7588] inet_recvmsg+0xbb/0x250 [ 64.309747][ T7588] ? apparmor_socket_recvmsg+0x3b/0x50 [ 64.315225][ T7588] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 64.321631][ T7588] ? security_socket_recvmsg+0x92/0xb0 [ 64.327089][ T7588] ? inet_sendpage+0x100/0x100 [ 64.331939][ T7588] sock_recvmsg+0x92/0xb0 [ 64.336534][ T7588] sock_read_iter+0x15f/0x1e0 [ 64.341349][ T7588] new_sync_read+0x389/0x4f0 [ 64.346057][ T7588] __vfs_read+0xb1/0xc0 [ 64.350486][ T7588] vfs_read+0x143/0x2c0 [ 64.354651][ T7588] ksys_read+0xd5/0x1b0 [ 64.358808][ T7588] __x64_sys_read+0x4c/0x60 [ 64.363446][ T7588] do_syscall_64+0xcc/0x370 [ 64.368328][ T7588] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 64.374239][ T7588] RIP: 0033:0x47c530 [ 64.378141][ T7588] 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 [ 64.397860][ T7588] RSP: 002b:000000c4204af7d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 64.406350][ T7588] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 64.414396][ T7588] RDX: 0000000000001000 RSI: 000000c420372000 RDI: 0000000000000003 [ 64.422447][ T7588] RBP: 000000c4204af830 R08: 0000000000000000 R09: 0000000000000000 [ 64.430550][ T7588] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000020 [ 64.438598][ T7588] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 64.447915][ T7588] Kernel Offset: disabled [ 64.452354][ T7588] Rebooting in 86400 seconds..