[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 38.994934][ T23] audit: type=1800 audit(1572091286.844:25): pid=7092 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 39.031534][ T23] audit: type=1800 audit(1572091286.844:26): pid=7092 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 39.105648][ T23] audit: type=1800 audit(1572091286.844:27): pid=7092 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 '10.128.15.207' (ECDSA) to the list of known hosts. 2019/10/26 12:01:34 fuzzer started 2019/10/26 12:01:35 dialing manager at 10.128.0.105:33655 2019/10/26 12:01:36 syscalls: 2533 2019/10/26 12:01:36 code coverage: enabled 2019/10/26 12:01:36 comparison tracing: enabled 2019/10/26 12:01:36 extra coverage: extra coverage is not supported by the kernel 2019/10/26 12:01:36 setuid sandbox: enabled 2019/10/26 12:01:36 namespace sandbox: enabled 2019/10/26 12:01:36 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/26 12:01:36 fault injection: enabled 2019/10/26 12:01:36 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/26 12:01:36 net packet injection: enabled 2019/10/26 12:01:36 net device setup: enabled 2019/10/26 12:01:36 concurrency sanitizer: enabled syzkaller login: [ 52.583305][ T7261] KCSAN: could not find function: 'poll_schedule_timeout' 2019/10/26 12:01:43 adding functions to KCSAN blacklist: 'ext4_free_inodes_count' 'rcu_gp_fqs_check_wake' 'taskstats_exit' 'get_task_cred' 'vm_area_dup' 'ext4_free_inode' 'pid_update_inode' 'tcp_poll' 'find_get_pages_range_tag' 'mod_timer' 'generic_write_end' 'tcp_add_backlog' 'ktime_get_real_seconds' 'find_next_bit' '__nf_conntrack_find_get' 'shmem_file_read_iter' 'ext4_has_free_clusters' 'poll_schedule_timeout' 'tomoyo_supervisor' 'pipe_poll' '__nf_ct_refresh_acct' 'add_timer' 'common_perm_cond' 'generic_permission' 'rcu_gp_fqs_loop' '__hrtimer_run_queues' 'do_nanosleep' 'tick_do_update_jiffies64' '__ext4_new_inode' 'ep_poll' 'kvm_arch_vcpu_load' 'update_defense_level' [ 73.185750][ T7244] ================================================================== [ 73.193899][ T7244] BUG: KCSAN: data-race in ktime_get_seconds / timekeeping_advance [ 73.201776][ T7244] [ 73.204105][ T7244] write to 0xffffffff86040b08 of 280 bytes by interrupt on cpu 0: [ 73.211907][ T7244] timekeeping_advance+0x893/0xd80 [ 73.217102][ T7244] update_wall_time+0x19/0x20 [ 73.221777][ T7244] tick_do_update_jiffies64+0x1ae/0x260 [ 73.227328][ T7244] tick_sched_do_timer+0xd4/0xe0 [ 73.232263][ T7244] tick_sched_timer+0x43/0xe0 [ 73.236929][ T7244] __hrtimer_run_queues+0x288/0x600 [ 73.242116][ T7244] hrtimer_interrupt+0x22a/0x480 [ 73.247052][ T7244] smp_apic_timer_interrupt+0xdc/0x280 [ 73.252532][ T7244] apic_timer_interrupt+0xf/0x20 [ 73.257445][ T7244] page_to_skb+0x427/0x480 [ 73.261838][ T7244] receive_buf+0x17c7/0x30b0 [ 73.266444][ T7244] virtnet_poll+0x436/0x7d0 [ 73.270934][ T7244] net_rx_action+0x3ae/0xa90 [ 73.275498][ T7244] __do_softirq+0x115/0x33f [ 73.279993][ T7244] [ 73.282300][ T7244] read to 0xffffffff86040b80 of 8 bytes by task 7244 on cpu 1: [ 73.289815][ T7244] ktime_get_seconds+0x45/0x70 [ 73.294581][ T7244] tcp_rcv_established+0xeeb/0xf50 [ 73.299677][ T7244] tcp_v4_do_rcv+0x381/0x4e0 [ 73.304242][ T7244] __release_sock+0x135/0x1e0 [ 73.308905][ T7244] release_sock+0x61/0x160 [ 73.313309][ T7244] tcp_recvmsg+0x63b/0x1a30 [ 73.317797][ T7244] inet_recvmsg+0xbb/0x250 [ 73.322187][ T7244] sock_recvmsg+0x92/0xb0 [ 73.326493][ T7244] sock_read_iter+0x15f/0x1e0 [ 73.331158][ T7244] new_sync_read+0x389/0x4f0 [ 73.335723][ T7244] __vfs_read+0xb1/0xc0 [ 73.339851][ T7244] vfs_read+0x143/0x2c0 [ 73.343979][ T7244] ksys_read+0xd5/0x1b0 [ 73.348101][ T7244] [ 73.350400][ T7244] Reported by Kernel Concurrency Sanitizer on: [ 73.356539][ T7244] CPU: 1 PID: 7244 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 73.363966][ T7244] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 73.373992][ T7244] ================================================================== [ 73.382029][ T7244] Kernel panic - not syncing: panic_on_warn set ... [ 73.388593][ T7244] CPU: 1 PID: 7244 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 73.396095][ T7244] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 73.406251][ T7244] Call Trace: [ 73.409591][ T7244] dump_stack+0xf5/0x159 [ 73.413827][ T7244] panic+0x210/0x640 [ 73.417711][ T7244] ? sock_read_iter+0x15f/0x1e0 [ 73.422543][ T7244] ? vprintk_func+0x8d/0x140 [ 73.427301][ T7244] kcsan_report.cold+0xc/0x10 [ 73.431969][ T7244] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 73.437495][ T7244] __tsan_read8+0x2c/0x30 [ 73.441811][ T7244] ktime_get_seconds+0x45/0x70 [ 73.446554][ T7244] tcp_rcv_established+0xeeb/0xf50 [ 73.451643][ T7244] ? ipv4_dst_check+0xc6/0xf0 [ 73.456314][ T7244] tcp_v4_do_rcv+0x381/0x4e0 [ 73.460894][ T7244] __release_sock+0x135/0x1e0 [ 73.465548][ T7244] release_sock+0x61/0x160 [ 73.469942][ T7244] tcp_recvmsg+0x63b/0x1a30 [ 73.474430][ T7244] inet_recvmsg+0xbb/0x250 [ 73.478824][ T7244] ? __tsan_read8+0x2c/0x30 [ 73.483312][ T7244] ? inet_sendpage+0x100/0x100 [ 73.488052][ T7244] sock_recvmsg+0x92/0xb0 [ 73.492363][ T7244] sock_read_iter+0x15f/0x1e0 [ 73.497022][ T7244] new_sync_read+0x389/0x4f0 [ 73.501603][ T7244] __vfs_read+0xb1/0xc0 [ 73.505737][ T7244] vfs_read+0x143/0x2c0 [ 73.509886][ T7244] ksys_read+0xd5/0x1b0 [ 73.514019][ T7244] __x64_sys_read+0x4c/0x60 [ 73.518505][ T7244] do_syscall_64+0xcc/0x370 [ 73.522991][ T7244] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 73.528858][ T7244] RIP: 0033:0x47c530 [ 73.532732][ T7244] 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 [ 73.552329][ T7244] RSP: 002b:000000c4203c37d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 73.560729][ T7244] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 73.568770][ T7244] RDX: 0000000000001000 RSI: 000000c420162000 RDI: 0000000000000003 [ 73.576719][ T7244] RBP: 000000c4203c3830 R08: 0000000000000000 R09: 0000000000000000 [ 73.584666][ T7244] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000100 [ 73.592614][ T7244] R13: ffffffffffffffff R14: 0000000000000010 R15: ffffffffffffffff [ 73.601996][ T7244] Kernel Offset: disabled [ 73.606331][ T7244] Rebooting in 86400 seconds..