[....] 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. [ 47.577717][ T26] kauditd_printk_skb: 7 callbacks suppressed [ 47.577731][ T26] audit: type=1800 audit(1576171323.317:29): pid=7320 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 [ 47.617744][ T26] audit: type=1800 audit(1576171323.317:30): pid=7320 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 '10.128.0.183' (ECDSA) to the list of known hosts. 2019/12/12 17:22:14 fuzzer started 2019/12/12 17:22:16 dialing manager at 10.128.0.105:37995 2019/12/12 17:22:16 syscalls: 2689 2019/12/12 17:22:16 code coverage: enabled 2019/12/12 17:22:16 comparison tracing: enabled 2019/12/12 17:22:16 extra coverage: extra coverage is not supported by the kernel 2019/12/12 17:22:16 setuid sandbox: enabled 2019/12/12 17:22:16 namespace sandbox: enabled 2019/12/12 17:22:16 Android sandbox: /sys/fs/selinux/policy does not exist 2019/12/12 17:22:16 fault injection: enabled 2019/12/12 17:22:16 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/12/12 17:22:16 net packet injection: enabled 2019/12/12 17:22:16 net device setup: enabled 2019/12/12 17:22:16 concurrency sanitizer: enabled 2019/12/12 17:22:16 devlink PCI setup: PCI device 0000:00:10.0 is not available 2019/12/12 17:22:17 adding functions to KCSAN blacklist: 'tomoyo_supervisor' '__hrtimer_run_queues' '__splice_from_pipe' syzkaller login: [ 61.821783][ T7485] ================================================================== [ 61.829916][ T7485] BUG: KCSAN: data-race in tcp_add_backlog / tcp_recvmsg [ 61.837552][ T7485] [ 61.839879][ T7485] write to 0xffff888122a412f8 of 8 bytes by interrupt on cpu 0: [ 61.847499][ T7485] tcp_add_backlog+0x476/0xce0 [ 61.852252][ T7485] tcp_v4_rcv+0x1a70/0x1bd0 [ 61.856747][ T7485] ip_protocol_deliver_rcu+0x4d/0x420 [ 61.862102][ T7485] ip_local_deliver_finish+0x110/0x140 [ 61.867542][ T7485] ip_local_deliver+0x133/0x210 [ 61.872383][ T7485] ip_rcv_finish+0x121/0x160 [ 61.876965][ T7485] ip_rcv+0x18f/0x1a0 [ 61.880928][ T7485] __netif_receive_skb_one_core+0xa7/0xe0 [ 61.886650][ T7485] __netif_receive_skb+0x37/0xf0 [ 61.891567][ T7485] netif_receive_skb_internal+0x59/0x190 [ 61.897191][ T7485] napi_gro_receive+0x28f/0x330 [ 61.902040][ T7485] receive_buf+0x284/0x30b0 [ 61.907393][ T7485] virtnet_poll+0x436/0x7d0 [ 61.911888][ T7485] net_rx_action+0x3ae/0xa90 [ 61.916473][ T7485] __do_softirq+0x115/0x33f [ 61.920979][ T7485] run_ksoftirqd+0x46/0x60 [ 61.925386][ T7485] smpboot_thread_fn+0x37d/0x4a0 [ 61.930324][ T7485] kthread+0x1d4/0x200 [ 61.934730][ T7485] ret_from_fork+0x1f/0x30 [ 61.939124][ T7485] [ 61.941455][ T7485] read to 0xffff888122a412f8 of 8 bytes by task 7485 on cpu 1: [ 61.949057][ T7485] tcp_recvmsg+0x46e/0x1b40 [ 61.953833][ T7485] inet_recvmsg+0xbb/0x250 [ 61.958241][ T7485] sock_recvmsg+0x92/0xb0 [ 61.962655][ T7485] sock_read_iter+0x15f/0x1e0 [ 61.967348][ T7485] new_sync_read+0x389/0x4f0 [ 61.971926][ T7485] __vfs_read+0xb1/0xc0 [ 61.976089][ T7485] vfs_read+0x143/0x2c0 [ 61.980420][ T7485] ksys_read+0xd5/0x1b0 [ 61.984561][ T7485] __x64_sys_read+0x4c/0x60 [ 61.989136][ T7485] do_syscall_64+0xcc/0x370 [ 61.993712][ T7485] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 61.999604][ T7485] [ 62.001925][ T7485] Reported by Kernel Concurrency Sanitizer on: [ 62.008061][ T7485] CPU: 1 PID: 7485 Comm: syz-fuzzer Not tainted 5.4.0-syzkaller #0 [ 62.015926][ T7485] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.025963][ T7485] ================================================================== [ 62.034021][ T7485] Kernel panic - not syncing: panic_on_warn set ... [ 62.041740][ T7485] CPU: 1 PID: 7485 Comm: syz-fuzzer Not tainted 5.4.0-syzkaller #0 [ 62.049630][ T7485] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.060621][ T7485] Call Trace: [ 62.064072][ T7485] dump_stack+0x11d/0x181 [ 62.068693][ T7485] panic+0x210/0x640 [ 62.072579][ T7485] ? vprintk_func+0x8d/0x140 [ 62.077166][ T7485] kcsan_report.cold+0xc/0xd [ 62.081759][ T7485] kcsan_setup_watchpoint+0x3fe/0x460 [ 62.087126][ T7485] __tsan_read8+0xc6/0x100 [ 62.091690][ T7485] tcp_recvmsg+0x46e/0x1b40 [ 62.096206][ T7485] ? preempt_schedule_common+0x37/0x90 [ 62.101677][ T7485] inet_recvmsg+0xbb/0x250 [ 62.106080][ T7485] ? apparmor_socket_recvmsg+0x3b/0x50 [ 62.111542][ T7485] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 62.119503][ T7485] ? security_socket_recvmsg+0x92/0xb0 [ 62.124960][ T7485] ? inet_sendpage+0x100/0x100 [ 62.130313][ T7485] sock_recvmsg+0x92/0xb0 [ 62.134747][ T7485] sock_read_iter+0x15f/0x1e0 [ 62.139423][ T7485] new_sync_read+0x389/0x4f0 [ 62.144549][ T7485] __vfs_read+0xb1/0xc0 [ 62.148703][ T7485] vfs_read+0x143/0x2c0 [ 62.152856][ T7485] ksys_read+0xd5/0x1b0 [ 62.157007][ T7485] __x64_sys_read+0x4c/0x60 [ 62.161682][ T7485] do_syscall_64+0xcc/0x370 [ 62.166188][ T7485] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 62.172270][ T7485] RIP: 0033:0x47c530 [ 62.176253][ T7485] 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 [ 62.195838][ T7485] RSP: 002b:000000c4202ee810 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 [ 62.204510][ T7485] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 62.212742][ T7485] RDX: 0000000000001000 RSI: 000000c4203d6000 RDI: 0000000000000003 [ 62.220761][ T7485] RBP: 000000c4202ee868 R08: 0000000000000000 R09: 0000000000000000 [ 62.228750][ T7485] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008 [ 62.236871][ T7485] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 62.246730][ T7485] Kernel Offset: disabled [ 62.251230][ T7485] Rebooting in 86400 seconds..