[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 34.984309][ T26] audit: type=1800 audit(1571524131.624:25): pid=6996 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.004047][ T26] audit: type=1800 audit(1571524131.624:26): pid=6996 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.025904][ T26] audit: type=1800 audit(1571524131.624:27): pid=6996 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 '10.128.0.86' (ECDSA) to the list of known hosts. 2019/10/19 22:28:59 fuzzer started 2019/10/19 22:29:00 dialing manager at 10.128.0.105:43535 2019/10/19 22:29:00 syscalls: 2524 2019/10/19 22:29:00 code coverage: enabled 2019/10/19 22:29:00 comparison tracing: enabled 2019/10/19 22:29:00 extra coverage: extra coverage is not supported by the kernel 2019/10/19 22:29:00 setuid sandbox: enabled 2019/10/19 22:29:00 namespace sandbox: enabled 2019/10/19 22:29:00 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/19 22:29:00 fault injection: enabled 2019/10/19 22:29:00 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/19 22:29:00 net packet injection: enabled 2019/10/19 22:29:00 net device setup: enabled 2019/10/19 22:29:00 concurrency sanitizer: enabled syzkaller login: [ 44.724039][ T7148] ================================================================== [ 44.732182][ T7148] BUG: KCSAN: data-race in mod_timer / timer_clear_idle [ 44.739115][ T7148] [ 44.741430][ T7148] write to 0xffff88812bf1b6e4 of 1 bytes by task 0 on cpu 1: [ 44.748783][ T7148] timer_clear_idle+0x42/0x50 [ 44.753442][ T7148] __tick_nohz_idle_restart_tick+0x36/0x1b0 [ 44.759319][ T7148] tick_nohz_idle_exit+0x1af/0x1e0 [ 44.764432][ T7148] do_idle+0xb1/0x280 [ 44.768396][ T7148] cpu_startup_entry+0x1b/0x20 [ 44.773140][ T7148] start_secondary+0x208/0x260 [ 44.777888][ T7148] secondary_startup_64+0xa4/0xb0 [ 44.782885][ T7148] [ 44.785200][ T7148] read to 0xffff88812bf1b6e4 of 1 bytes by task 7148 on cpu 0: [ 44.792723][ T7148] mod_timer+0x50d/0x7a0 [ 44.796956][ T7148] sk_reset_timer+0x2d/0x70 [ 44.801443][ T7148] tcp_send_delayed_ack+0x21d/0x2b0 [ 44.806625][ T7148] __tcp_ack_snd_check+0x3d1/0x4f0 [ 44.811721][ T7148] tcp_rcv_established+0xce9/0xf50 [ 44.816814][ T7148] tcp_v4_do_rcv+0x381/0x4e0 [ 44.821395][ T7148] __release_sock+0x135/0x1e0 [ 44.826052][ T7148] release_sock+0x61/0x160 [ 44.830455][ T7148] tcp_recvmsg+0x63b/0x1a30 [ 44.834938][ T7148] inet_recvmsg+0xbb/0x250 [ 44.839347][ T7148] sock_recvmsg+0x92/0xb0 [ 44.843659][ T7148] sock_read_iter+0x15f/0x1e0 [ 44.848420][ T7148] new_sync_read+0x389/0x4f0 [ 44.852983][ T7148] [ 44.855291][ T7148] Reported by Kernel Concurrency Sanitizer on: [ 44.861428][ T7148] CPU: 0 PID: 7148 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 44.868860][ T7148] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.878896][ T7148] ================================================================== [ 44.886936][ T7148] Kernel panic - not syncing: panic_on_warn set ... [ 44.893505][ T7148] CPU: 0 PID: 7148 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 44.900935][ T7148] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.910970][ T7148] Call Trace: [ 44.914253][ T7148] dump_stack+0xf5/0x159 [ 44.918479][ T7148] panic+0x210/0x640 [ 44.922371][ T7148] ? tcp_recvmsg+0x63b/0x1a30 [ 44.927051][ T7148] ? vprintk_func+0x8d/0x140 [ 44.931638][ T7148] kcsan_report.cold+0xc/0x10 [ 44.936301][ T7148] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 44.941830][ T7148] __tsan_read1+0x2c/0x30 [ 44.946145][ T7148] mod_timer+0x50d/0x7a0 [ 44.950472][ T7148] sk_reset_timer+0x2d/0x70 [ 44.954959][ T7148] tcp_send_delayed_ack+0x21d/0x2b0 [ 44.960148][ T7148] __tcp_ack_snd_check+0x3d1/0x4f0 [ 44.965260][ T7148] tcp_rcv_established+0xce9/0xf50 [ 44.970359][ T7148] ? ipv4_dst_check+0xc6/0xf0 [ 44.975026][ T7148] tcp_v4_do_rcv+0x381/0x4e0 [ 44.979610][ T7148] __release_sock+0x135/0x1e0 [ 44.984371][ T7148] release_sock+0x61/0x160 [ 44.988774][ T7148] tcp_recvmsg+0x63b/0x1a30 [ 44.993281][ T7148] inet_recvmsg+0xbb/0x250 [ 44.997699][ T7148] ? __tsan_read8+0x2c/0x30 [ 45.002189][ T7148] ? inet_sendpage+0x100/0x100 [ 45.006938][ T7148] sock_recvmsg+0x92/0xb0 [ 45.011253][ T7148] sock_read_iter+0x15f/0x1e0 [ 45.015920][ T7148] new_sync_read+0x389/0x4f0 [ 45.020502][ T7148] __vfs_read+0xb1/0xc0 [ 45.024645][ T7148] vfs_read+0x143/0x2c0 [ 45.028785][ T7148] ksys_read+0xd5/0x1b0 [ 45.032929][ T7148] __x64_sys_read+0x4c/0x60 [ 45.037511][ T7148] do_syscall_64+0xcc/0x370 [ 45.042000][ T7148] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 45.047876][ T7148] RIP: 0033:0x47c530 [ 45.051777][ T7148] 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 [ 45.071362][ T7148] RSP: 002b:000000c4204e5810 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 [ 45.079760][ T7148] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 45.087716][ T7148] RDX: 0000000000001000 RSI: 000000c4203a6000 RDI: 0000000000000003 [ 45.095676][ T7148] RBP: 000000c4204e5868 R08: 0000000000000000 R09: 0000000000000000 [ 45.103630][ T7148] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000007 [ 45.111582][ T7148] R13: 000000c4200211f0 R14: 0000000000000004 R15: ffffffffffffffff [ 46.243927][ T7148] Shutting down cpus with NMI [ 46.250219][ T7148] Kernel Offset: disabled [ 46.254545][ T7148] Rebooting in 86400 seconds..