[ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.1.14' (ECDSA) to the list of known hosts. 2020/06/20 00:13:02 fuzzer started 2020/06/20 00:13:03 dialing manager at 10.128.0.105:38669 2020/06/20 00:13:03 syscalls: 3092 2020/06/20 00:13:03 code coverage: enabled 2020/06/20 00:13:03 comparison tracing: enabled 2020/06/20 00:13:03 extra coverage: enabled 2020/06/20 00:13:03 setuid sandbox: enabled 2020/06/20 00:13:03 namespace sandbox: enabled 2020/06/20 00:13:03 Android sandbox: /sys/fs/selinux/policy does not exist 2020/06/20 00:13:03 fault injection: enabled 2020/06/20 00:13:03 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2020/06/20 00:13:03 net packet injection: enabled 2020/06/20 00:13:03 net device setup: enabled 2020/06/20 00:13:03 concurrency sanitizer: enabled 2020/06/20 00:13:03 devlink PCI setup: PCI device 0000:00:10.0 is not available 2020/06/20 00:13:03 USB emulation: enabled 2020/06/20 00:13:06 suppressing KCSAN reports in functions: 'complete_signal' 'find_get_pages_range_tag' 'do_epoll_wait' 'ext4_free_inode' 'xas_clear_mark' 'dput' 'fsnotify' 'wbt_issue' 'alloc_pid' 'ext4_ext_insert_extent' 'shmem_file_read_iter' 'ext4_mark_iloc_dirty' 'audit_log_start' 'page_counter_charge' 'copy_process' 'ext4_mb_find_by_goal' 'exit_mm' 'atime_needs_update' 'n_tty_receive_buf_common' 'futex_wait_queue_me' 'blk_mq_dispatch_rq_list' 'generic_write_end' 'tick_nohz_stop_tick' 'snd_rawmidi_poll' 'shmem_symlink' '__ext4_new_inode' 'io_sq_thread' 'do_signal_stop' 'do_select' '__mark_inode_dirty' 'blk_mq_rq_ctx_init' 'pcpu_alloc' '__delayacct_blkio_end' 'expire_timers' 'blk_mq_sched_dispatch_requests' '__ext4_update_other_inode_time' 'dd_has_work' 'do_nanosleep' '__blk_mq_sched_dispatch_requests' '__xa_clear_mark' 'ext4_free_inodes_count' syzkaller login: [ 68.496534][ C1] ================================================================== [ 68.504637][ C1] BUG: KCSAN: data-race in __mod_timer / timer_clear_idle [ 68.511725][ C1] [ 68.514026][ C1] write to 0xffff88812c01cb24 of 1 bytes by task 0 on cpu 0: [ 68.521713][ C1] timer_clear_idle+0x2e/0x40 [ 68.526380][ C1] tick_nohz_idle_retain_tick+0x3e/0x40 [ 68.531895][ C1] do_idle+0x290/0x320 [ 68.535940][ C1] cpu_startup_entry+0x15/0x20 [ 68.540689][ C1] rest_init+0xd8/0xe0 [ 68.544741][ C1] arch_call_rest_init+0xa/0xb [ 68.549472][ C1] start_kernel+0x608/0x6d0 [ 68.555184][ C1] secondary_startup_64+0xa4/0xb0 [ 68.560187][ C1] [ 68.562513][ C1] read to 0xffff88812c01cb24 of 1 bytes by interrupt on cpu 1: [ 68.570025][ C1] __mod_timer+0xb87/0xf00 [ 68.574424][ C1] mod_timer+0x1b/0x20 [ 68.578473][ C1] sk_reset_timer+0x1f/0xa0 [ 68.582946][ C1] tcp_send_delayed_ack+0x191/0x250 [ 68.588111][ C1] __tcp_ack_snd_check+0x326/0x500 [ 68.593362][ C1] tcp_rcv_established+0xed6/0x1110 [ 68.598614][ C1] tcp_v4_do_rcv+0x25e/0x480 [ 68.603183][ C1] tcp_v4_rcv+0x2159/0x23e0 [ 68.607656][ C1] ip_protocol_deliver_rcu+0x1f9/0x400 [ 68.613356][ C1] ip_local_deliver+0x1d6/0x2a0 [ 68.618276][ C1] ip_sublist_rcv+0x4d4/0x5a0 [ 68.623006][ C1] ip_list_rcv+0x262/0x290 [ 68.627564][ C1] __netif_receive_skb_list_core+0x34b/0x450 [ 68.633529][ C1] __netif_receive_skb_list+0x298/0x310 [ 68.639045][ C1] netif_receive_skb_list_internal+0xda/0x330 [ 68.645090][ C1] napi_gro_receive+0x329/0x5a0 [ 68.649935][ C1] receive_buf+0x7a4/0xcf0 [ 68.654327][ C1] virtnet_poll+0x2fa/0x780 [ 68.658814][ C1] napi_poll+0x154/0x480 [ 68.663031][ C1] net_rx_action+0x1ba/0x530 [ 68.667612][ C1] __do_softirq+0x198/0x360 [ 68.672088][ C1] run_ksoftirqd+0x2f/0x60 [ 68.676475][ C1] smpboot_thread_fn+0x347/0x530 [ 68.681381][ C1] kthread+0x210/0x220 [ 68.685420][ C1] ret_from_fork+0x1f/0x30 [ 68.689988][ C1] [ 68.692293][ C1] Reported by Kernel Concurrency Sanitizer on: [ 68.698437][ C1] CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.8.0-rc1-syzkaller #0 [ 68.706555][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 68.716667][ C1] ================================================================== [ 68.724697][ C1] Kernel panic - not syncing: panic_on_warn set ... [ 68.731265][ C1] CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.8.0-rc1-syzkaller #0 [ 68.739413][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 68.750051][ C1] Call Trace: [ 68.753325][ C1] dump_stack+0x10f/0x19d [ 68.757630][ C1] panic+0x1f8/0x63a [ 68.761493][ C1] ? vprintk_emit+0x44a/0x4f0 [ 68.766151][ C1] kcsan_report+0x684/0x690 [ 68.770642][ C1] ? kcsan_setup_watchpoint+0x453/0x4d0 [ 68.776281][ C1] ? __mod_timer+0xb87/0xf00 [ 68.780845][ C1] ? mod_timer+0x1b/0x20 [ 68.785057][ C1] ? sk_reset_timer+0x1f/0xa0 [ 68.789702][ C1] ? tcp_send_delayed_ack+0x191/0x250 [ 68.795051][ C1] ? __tcp_ack_snd_check+0x326/0x500 [ 68.800318][ C1] ? tcp_rcv_established+0xed6/0x1110 [ 68.805665][ C1] ? tcp_v4_do_rcv+0x25e/0x480 [ 68.810398][ C1] ? tcp_v4_rcv+0x2159/0x23e0 [ 68.815042][ C1] ? ip_protocol_deliver_rcu+0x1f9/0x400 [ 68.820640][ C1] ? ip_local_deliver+0x1d6/0x2a0 [ 68.825630][ C1] ? ip_sublist_rcv+0x4d4/0x5a0 [ 68.830455][ C1] ? ip_list_rcv+0x262/0x290 [ 68.835011][ C1] ? __netif_receive_skb_list_core+0x34b/0x450 [ 68.841133][ C1] ? __netif_receive_skb_list+0x298/0x310 [ 68.846819][ C1] ? netif_receive_skb_list_internal+0xda/0x330 [ 68.853026][ C1] ? napi_gro_receive+0x329/0x5a0 [ 68.858020][ C1] ? receive_buf+0x7a4/0xcf0 [ 68.862683][ C1] ? virtnet_poll+0x2fa/0x780 [ 68.867334][ C1] ? napi_poll+0x154/0x480 [ 68.871718][ C1] ? net_rx_action+0x1ba/0x530 [ 68.876468][ C1] ? __do_softirq+0x198/0x360 [ 68.881113][ C1] ? run_ksoftirqd+0x2f/0x60 [ 68.885680][ C1] ? smpboot_thread_fn+0x347/0x530 [ 68.890766][ C1] ? kthread+0x210/0x220 [ 68.894976][ C1] ? ret_from_fork+0x1f/0x30 [ 68.899541][ C1] ? __tcp_select_window+0x340/0x510 [ 68.904797][ C1] ? check_preemption_disabled+0x3f/0x1a0 [ 68.910486][ C1] ? debug_smp_processor_id+0x18/0x20 [ 68.915838][ C1] ? debug_smp_processor_id+0x18/0x20 [ 68.921184][ C1] kcsan_setup_watchpoint+0x453/0x4d0 [ 68.926540][ C1] ? debug_smp_processor_id+0x18/0x20 [ 68.931885][ C1] __mod_timer+0xb87/0xf00 [ 68.936287][ C1] mod_timer+0x1b/0x20 [ 68.940451][ C1] sk_reset_timer+0x1f/0xa0 [ 68.944930][ C1] tcp_send_delayed_ack+0x191/0x250 [ 68.950223][ C1] __tcp_ack_snd_check+0x326/0x500 [ 68.955315][ C1] tcp_rcv_established+0xed6/0x1110 [ 68.960491][ C1] tcp_v4_do_rcv+0x25e/0x480 [ 68.965054][ C1] tcp_v4_rcv+0x2159/0x23e0 [ 68.969534][ C1] ? nf_confirm+0x201/0x230 [ 68.974023][ C1] ip_protocol_deliver_rcu+0x1f9/0x400 [ 68.979467][ C1] ip_local_deliver+0x1d6/0x2a0 [ 68.984469][ C1] ? ip_local_deliver+0x2a0/0x2a0 [ 68.989460][ C1] ip_sublist_rcv+0x4d4/0x5a0 [ 68.994121][ C1] ? ip_rcv_core+0x620/0x620 [ 68.998676][ C1] ip_list_rcv+0x262/0x290 [ 69.003214][ C1] ? ip_rcv_finish+0x160/0x160 [ 69.007952][ C1] __netif_receive_skb_list_core+0x34b/0x450 [ 69.013907][ C1] __netif_receive_skb_list+0x298/0x310 [ 69.019420][ C1] ? receive_mergeable+0x45f/0x1af0 [ 69.024592][ C1] netif_receive_skb_list_internal+0xda/0x330 [ 69.030628][ C1] napi_gro_receive+0x329/0x5a0 [ 69.035450][ C1] receive_buf+0x7a4/0xcf0 [ 69.039930][ C1] virtnet_poll+0x2fa/0x780 [ 69.045199][ C1] napi_poll+0x154/0x480 [ 69.049420][ C1] net_rx_action+0x1ba/0x530 [ 69.053980][ C1] __do_softirq+0x198/0x360 [ 69.058456][ C1] ? ksoftirqd_should_run+0x20/0x20 [ 69.063621][ C1] run_ksoftirqd+0x2f/0x60 [ 69.068016][ C1] smpboot_thread_fn+0x347/0x530 [ 69.072940][ C1] ? cpu_report_death+0x80/0x80 [ 69.077807][ C1] kthread+0x210/0x220 [ 69.081859][ C1] ? cpu_report_death+0x80/0x80 [ 69.086679][ C1] ? constant_test_bit+0x30/0x30 [ 69.091807][ C1] ret_from_fork+0x1f/0x30 [ 70.216308][ C1] Shutting down cpus with NMI [ 70.222470][ C1] Kernel Offset: disabled [ 70.226781][ C1] Rebooting in 86400 seconds..