[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 37.101999][ T25] audit: type=1800 audit(1572468883.066:25): pid=7052 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 37.129579][ T25] audit: type=1800 audit(1572468883.066:26): pid=7052 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 37.156826][ T25] audit: type=1800 audit(1572468883.066:27): pid=7052 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 '10.128.0.18' (ECDSA) to the list of known hosts. 2019/10/30 20:54:55 fuzzer started 2019/10/30 20:54:57 dialing manager at 10.128.0.105:37477 2019/10/30 20:54:58 syscalls: 2540 2019/10/30 20:54:58 code coverage: enabled 2019/10/30 20:54:58 comparison tracing: enabled 2019/10/30 20:54:58 extra coverage: extra coverage is not supported by the kernel 2019/10/30 20:54:58 setuid sandbox: enabled 2019/10/30 20:54:58 namespace sandbox: enabled 2019/10/30 20:54:58 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/30 20:54:58 fault injection: enabled 2019/10/30 20:54:58 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/30 20:54:58 net packet injection: enabled 2019/10/30 20:54:58 net device setup: enabled 2019/10/30 20:54:58 concurrency sanitizer: enabled 2019/10/30 20:55:02 adding functions to KCSAN blacklist: '__hrtimer_run_queues' 'tomoyo_supervisor' 'tick_do_update_jiffies64' 'ktime_get_real_seconds' 'task_dump_owner' 'generic_permission' '__tcp_select_window' 'pid_update_inode' 'find_next_bit' 'ep_poll' 'add_timer' 'mod_timer' 'tcp_add_backlog' '__nf_ct_refresh_acct' '__nf_conntrack_find_get' 'shmem_file_read_iter' 'do_nanosleep' 'tcp_poll' 'ext4_free_inode' syzkaller login: [ 59.831541][ C0] ================================================================== [ 59.839862][ C0] BUG: KCSAN: data-race in tick_sched_do_timer / tick_sched_do_timer [ 59.848132][ C0] [ 59.850474][ C0] write to 0xffffffff85cb2790 of 4 bytes by interrupt on cpu 1: [ 59.858084][ C0] tick_sched_do_timer+0xc0/0xe0 [ 59.863000][ C0] tick_sched_timer+0x43/0xe0 [ 59.867664][ C0] __hrtimer_run_queues+0x288/0x600 [ 59.872845][ C0] hrtimer_interrupt+0x22a/0x480 [ 59.877945][ C0] smp_apic_timer_interrupt+0xdc/0x280 [ 59.883382][ C0] apic_timer_interrupt+0xf/0x20 [ 59.888332][ C0] _raw_spin_unlock_irqrestore+0x51/0x80 [ 59.893944][ C0] try_to_wake_up+0x3d2/0x6e0 [ 59.898595][ C0] wake_up_q+0x3b/0x70 [ 59.902659][ C0] futex_wake+0x322/0x350 [ 59.906973][ C0] do_futex+0x2be/0x18d0 [ 59.911270][ C0] __x64_sys_futex+0x2cd/0x3f0 [ 59.916015][ C0] do_syscall_64+0xcc/0x370 [ 59.920494][ C0] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 59.926354][ C0] [ 59.928661][ C0] read to 0xffffffff85cb2790 of 4 bytes by interrupt on cpu 0: [ 59.936178][ C0] tick_sched_do_timer+0x33/0xe0 [ 59.941090][ C0] tick_sched_timer+0x43/0xe0 [ 59.945751][ C0] __hrtimer_run_queues+0x288/0x600 [ 59.950921][ C0] hrtimer_interrupt+0x22a/0x480 [ 59.955846][ C0] smp_apic_timer_interrupt+0xdc/0x280 [ 59.961278][ C0] apic_timer_interrupt+0xf/0x20 [ 59.966194][ C0] __kcsan_check_watchpoint+0xec/0x180 [ 59.971627][ C0] __tsan_write2+0x18/0x40 [ 59.976019][ C0] tcp_chrono_start+0xa4/0x130 [ 59.980757][ C0] skb_entail+0x3ac/0x3c0 [ 59.985072][ C0] tcp_sendmsg_locked+0x995/0x1f30 [ 59.990155][ C0] tcp_sendmsg+0x39/0x60 [ 59.994371][ C0] inet_sendmsg+0x6d/0x90 [ 59.998669][ C0] [ 60.000970][ C0] Reported by Kernel Concurrency Sanitizer on: [ 60.007115][ C0] CPU: 0 PID: 7203 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 60.014541][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 60.024582][ C0] ================================================================== [ 60.033244][ C0] Kernel panic - not syncing: panic_on_warn set ... [ 60.039840][ C0] CPU: 0 PID: 7203 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 60.047273][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 60.057307][ C0] Call Trace: [ 60.060569][ C0] [ 60.063404][ C0] dump_stack+0xf5/0x159 [ 60.067636][ C0] panic+0x210/0x640 [ 60.071533][ C0] ? tcp_chrono_start+0xa4/0x130 [ 60.076456][ C0] ? vprintk_func+0x8d/0x140 [ 60.081035][ C0] kcsan_report.cold+0xc/0x10 [ 60.085702][ C0] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 60.091236][ C0] __tsan_read4+0x2c/0x30 [ 60.095546][ C0] tick_sched_do_timer+0x33/0xe0 [ 60.100476][ C0] tick_sched_timer+0x43/0xe0 [ 60.105160][ C0] __hrtimer_run_queues+0x288/0x600 [ 60.110355][ C0] ? tick_sched_do_timer+0xe0/0xe0 [ 60.115461][ C0] hrtimer_interrupt+0x22a/0x480 [ 60.120389][ C0] smp_apic_timer_interrupt+0xdc/0x280 [ 60.125826][ C0] ? do_IRQ+0xcb/0x180 [ 60.129877][ C0] apic_timer_interrupt+0xf/0x20 [ 60.134793][ C0] [ 60.137709][ C0] RIP: 0010:__kcsan_check_watchpoint+0xec/0x180 [ 60.143943][ C0] Code: c3 49 89 c7 48 c1 eb 31 49 21 d7 81 e3 ff 3f 00 00 48 85 c0 78 05 45 84 c0 74 0f 4d 39 cf 77 0a 49 8d 5c 1f ff 48 39 df 76 3f <83> f9 03 75 8a 5b b8 01 00 00 00 41 5c 41 5d 41 5e 41 5f 5d c3 65 [ 60.163533][ C0] RSP: 0018:ffffc90002f3fa28 EFLAGS: 00000297 ORIG_RAX: ffffffffffffff13 [ 60.171919][ C0] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000003 [ 60.179875][ C0] RDX: 0000ffffffffffff RSI: 000000000000002b RDI: 000088812262b864 [ 60.187836][ C0] RBP: ffffc90002f3fa50 R08: 0000000000000001 R09: 000088812262b865 [ 60.195787][ C0] R10: 00000000aaaaaaab R11: ffffffff86045d70 R12: 0000000000000001 [ 60.203736][ C0] R13: ffff88812262b864 R14: 0000000000000002 R15: ffff88812262b854 [ 60.211710][ C0] __tsan_write2+0x18/0x40 [ 60.216114][ C0] tcp_chrono_start+0xa4/0x130 [ 60.220910][ C0] skb_entail+0x3ac/0x3c0 [ 60.225250][ C0] tcp_sendmsg_locked+0x995/0x1f30 [ 60.230376][ C0] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 60.236000][ C0] ? __tsan_read8+0x2c/0x30 [ 60.240480][ C0] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 60.246106][ C0] tcp_sendmsg+0x39/0x60 [ 60.250331][ C0] inet_sendmsg+0x6d/0x90 [ 60.254638][ C0] ? inet_send_prepare+0x200/0x200 [ 60.259729][ C0] sock_sendmsg+0x9f/0xc0 [ 60.264057][ C0] sock_write_iter+0x16b/0x210 [ 60.268801][ C0] new_sync_write+0x388/0x4a0 [ 60.273460][ C0] __vfs_write+0xb1/0xc0 [ 60.277680][ C0] vfs_write+0x18a/0x390 [ 60.281910][ C0] ksys_write+0xd5/0x1b0 [ 60.286134][ C0] __x64_sys_write+0x4c/0x60 [ 60.290715][ C0] do_syscall_64+0xcc/0x370 [ 60.295284][ C0] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 60.301239][ C0] RIP: 0033:0x47c530 [ 60.305117][ C0] 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 [ 60.324697][ C0] RSP: 002b:000000c42036d4f8 EFLAGS: 00000216 ORIG_RAX: 0000000000000001 [ 60.333092][ C0] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 60.341040][ C0] RDX: 0000000000000007 RSI: 000000c420358200 RDI: 0000000000000003 [ 60.348995][ C0] RBP: 000000c42036d550 R08: 0000000000000000 R09: 0000000000000000 [ 60.356945][ C0] R10: 0000000000000000 R11: 0000000000000216 R12: 000000c4200c3b00 [ 60.364893][ C0] R13: 000000000000000f R14: 0000000000c1d600 R15: 0000000000000c21 [ 60.374361][ C0] Kernel Offset: disabled [ 60.378693][ C0] Rebooting in 86400 seconds..