[ 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 '10.128.0.51' (ECDSA) to the list of known hosts. 2020/07/22 15:45:22 fuzzer started 2020/07/22 15:45:22 dialing manager at 10.128.0.105:37525 2020/07/22 15:45:22 syscalls: 3214 2020/07/22 15:45:22 code coverage: enabled 2020/07/22 15:45:22 comparison tracing: enabled 2020/07/22 15:45:22 extra coverage: enabled 2020/07/22 15:45:22 setuid sandbox: enabled 2020/07/22 15:45:22 namespace sandbox: enabled 2020/07/22 15:45:22 Android sandbox: /sys/fs/selinux/policy does not exist 2020/07/22 15:45:22 fault injection: enabled 2020/07/22 15:45:22 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2020/07/22 15:45:22 net packet injection: enabled 2020/07/22 15:45:22 net device setup: enabled 2020/07/22 15:45:22 concurrency sanitizer: enabled 2020/07/22 15:45:22 devlink PCI setup: PCI device 0000:00:10.0 is not available 2020/07/22 15:45:22 USB emulation: enabled 2020/07/22 15:45:25 suppressing KCSAN reports in functions: 'ext4_free_inodes_count' 'blk_mq_rq_ctx_init' 'find_get_pages_range_tag' '__ext4_new_inode' 'page_counter_charge' 'alloc_pid' '__xa_clear_mark' 'do_sys_poll' 'do_nanosleep' 'exit_mm' '__delayacct_blkio_end' 'expire_timers' 'pcpu_alloc' 'get_cpu_idle_time_us' '__delete_from_page_cache' 'generic_write_end' 'ext4_mb_regular_allocator' '__add_to_page_cache_locked' 'snd_rawmidi_kernel_write1' 'd_set_mounted' '__xa_set_mark' 'ext4_free_inode' 'blk_mq_sched_dispatch_requests' 'n_tty_receive_buf_common' 'blk_mq_dispatch_rq_list' 'do_epoll_wait' '__send_signal' 'xas_clear_mark' 'ext4_mb_find_by_goal' 'dd_has_work' 'inc_node_page_state' 'lookup_fast' syzkaller login: [ 72.187324][ C1] ================================================================== [ 72.195538][ C1] BUG: KCSAN: data-race in __mod_timer / timer_clear_idle [ 72.202610][ C1] [ 72.204911][ C1] write to 0xffff88812c01cb24 of 1 bytes by task 0 on cpu 0: [ 72.212247][ C1] timer_clear_idle+0x2e/0x40 [ 72.216942][ C1] tick_nohz_idle_retain_tick+0x3e/0x40 [ 72.222455][ C1] do_idle+0x287/0x310 [ 72.226491][ C1] cpu_startup_entry+0x15/0x20 [ 72.231237][ C1] rest_init+0xd8/0xe0 [ 72.235286][ C1] arch_call_rest_init+0xa/0xb [ 72.240115][ C1] start_kernel+0x608/0x6d0 [ 72.244594][ C1] secondary_startup_64+0xa4/0xb0 [ 72.249593][ C1] [ 72.251893][ C1] read to 0xffff88812c01cb24 of 1 bytes by interrupt on cpu 1: [ 72.259414][ C1] __mod_timer+0xbd7/0x1020 [ 72.263883][ C1] mod_timer+0x1b/0x20 [ 72.267920][ C1] sk_reset_timer+0x1f/0xa0 [ 72.272391][ C1] tcp_send_delayed_ack+0x191/0x250 [ 72.277567][ C1] __tcp_ack_snd_check+0x326/0x500 [ 72.282644][ C1] tcp_rcv_established+0x12e2/0x1520 [ 72.287982][ C1] tcp_v4_do_rcv+0x25e/0x480 [ 72.292551][ C1] tcp_v4_rcv+0x219b/0x2420 [ 72.297039][ C1] ip_protocol_deliver_rcu+0x1f9/0x400 [ 72.302554][ C1] ip_local_deliver+0x1d6/0x2a0 [ 72.307375][ C1] ip_sublist_rcv+0x4d4/0x5a0 [ 72.312019][ C1] ip_list_rcv+0x262/0x290 [ 72.316404][ C1] __netif_receive_skb_list_core+0x34b/0x450 [ 72.322362][ C1] __netif_receive_skb_list+0x298/0x310 [ 72.327875][ C1] netif_receive_skb_list_internal+0xda/0x330 [ 72.333908][ C1] napi_gro_receive+0x329/0x5a0 [ 72.338724][ C1] receive_buf+0x7a4/0xcf0 [ 72.343119][ C1] virtnet_poll+0x2fa/0x780 [ 72.347590][ C1] napi_poll+0x178/0x4a0 [ 72.351800][ C1] net_rx_action+0x1ba/0x530 [ 72.356357][ C1] __do_softirq+0x198/0x360 [ 72.360829][ C1] run_ksoftirqd+0x2f/0x60 [ 72.365212][ C1] smpboot_thread_fn+0x347/0x530 [ 72.370116][ C1] kthread+0x20d/0x230 [ 72.374158][ C1] ret_from_fork+0x1f/0x30 [ 72.378547][ C1] [ 72.380841][ C1] Reported by Kernel Concurrency Sanitizer on: [ 72.388265][ C1] CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.8.0-rc6-syzkaller #0 [ 72.396380][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 72.406414][ C1] ================================================================== [ 72.414456][ C1] Kernel panic - not syncing: panic_on_warn set ... [ 72.421012][ C1] CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.8.0-rc6-syzkaller #0 [ 72.429125][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 72.439149][ C1] Call Trace: [ 72.442409][ C1] dump_stack+0x10f/0x19d [ 72.446707][ C1] panic+0x207/0x64a [ 72.450575][ C1] ? vprintk_emit+0x44a/0x4f0 [ 72.455308][ C1] kcsan_report+0x684/0x690 [ 72.459788][ C1] ? kcsan_setup_watchpoint+0x453/0x4d0 [ 72.465314][ C1] ? __mod_timer+0xbd7/0x1020 [ 72.469960][ C1] ? mod_timer+0x1b/0x20 [ 72.474168][ C1] ? sk_reset_timer+0x1f/0xa0 [ 72.478825][ C1] ? tcp_send_delayed_ack+0x191/0x250 [ 72.484164][ C1] ? __tcp_ack_snd_check+0x326/0x500 [ 72.489417][ C1] ? tcp_rcv_established+0x12e2/0x1520 [ 72.494859][ C1] ? tcp_v4_do_rcv+0x25e/0x480 [ 72.499606][ C1] ? tcp_v4_rcv+0x219b/0x2420 [ 72.504250][ C1] ? ip_protocol_deliver_rcu+0x1f9/0x400 [ 72.509863][ C1] ? ip_local_deliver+0x1d6/0x2a0 [ 72.514868][ C1] ? ip_sublist_rcv+0x4d4/0x5a0 [ 72.519684][ C1] ? ip_list_rcv+0x262/0x290 [ 72.524241][ C1] ? __netif_receive_skb_list_core+0x34b/0x450 [ 72.530374][ C1] ? __netif_receive_skb_list+0x298/0x310 [ 72.536062][ C1] ? netif_receive_skb_list_internal+0xda/0x330 [ 72.542284][ C1] ? napi_gro_receive+0x329/0x5a0 [ 72.547288][ C1] ? receive_buf+0x7a4/0xcf0 [ 72.551845][ C1] ? virtnet_poll+0x2fa/0x780 [ 72.556501][ C1] ? napi_poll+0x178/0x4a0 [ 72.560884][ C1] ? net_rx_action+0x1ba/0x530 [ 72.565626][ C1] ? __do_softirq+0x198/0x360 [ 72.570270][ C1] ? run_ksoftirqd+0x2f/0x60 [ 72.574826][ C1] ? smpboot_thread_fn+0x347/0x530 [ 72.579903][ C1] ? kthread+0x20d/0x230 [ 72.584115][ C1] ? ret_from_fork+0x1f/0x30 [ 72.588681][ C1] ? __tcp_select_window+0x340/0x510 [ 72.593934][ C1] ? __list_del_entry_valid+0x54/0xc0 [ 72.599275][ C1] kcsan_setup_watchpoint+0x453/0x4d0 [ 72.604627][ C1] __mod_timer+0xbd7/0x1020 [ 72.609109][ C1] mod_timer+0x1b/0x20 [ 72.613145][ C1] sk_reset_timer+0x1f/0xa0 [ 72.617630][ C1] tcp_send_delayed_ack+0x191/0x250 [ 72.622811][ C1] __tcp_ack_snd_check+0x326/0x500 [ 72.627896][ C1] tcp_rcv_established+0x12e2/0x1520 [ 72.633149][ C1] tcp_v4_do_rcv+0x25e/0x480 [ 72.637710][ C1] tcp_v4_rcv+0x219b/0x2420 [ 72.642185][ C1] ip_protocol_deliver_rcu+0x1f9/0x400 [ 72.647679][ C1] ip_local_deliver+0x1d6/0x2a0 [ 72.652509][ C1] ? ip_local_deliver+0x2a0/0x2a0 [ 72.657545][ C1] ip_sublist_rcv+0x4d4/0x5a0 [ 72.662202][ C1] ? ip_rcv_core+0x620/0x620 [ 72.666764][ C1] ip_list_rcv+0x262/0x290 [ 72.671147][ C1] ? ip_rcv_finish+0x160/0x160 [ 72.675966][ C1] __netif_receive_skb_list_core+0x34b/0x450 [ 72.681914][ C1] __netif_receive_skb_list+0x298/0x310 [ 72.687428][ C1] ? receive_mergeable+0x45f/0x1af0 [ 72.692614][ C1] netif_receive_skb_list_internal+0xda/0x330 [ 72.698650][ C1] napi_gro_receive+0x329/0x5a0 [ 72.703496][ C1] receive_buf+0x7a4/0xcf0 [ 72.707880][ C1] virtnet_poll+0x2fa/0x780 [ 72.712353][ C1] napi_poll+0x178/0x4a0 [ 72.716565][ C1] net_rx_action+0x1ba/0x530 [ 72.721136][ C1] __do_softirq+0x198/0x360 [ 72.725622][ C1] ? ksoftirqd_should_run+0x20/0x20 [ 72.730801][ C1] run_ksoftirqd+0x2f/0x60 [ 72.735186][ C1] smpboot_thread_fn+0x347/0x530 [ 72.740090][ C1] ? cpu_report_death+0x80/0x80 [ 72.744908][ C1] kthread+0x20d/0x230 [ 72.748945][ C1] ? cpu_report_death+0x80/0x80 [ 72.753767][ C1] ? kthread_blkcg+0x80/0x80 [ 72.758326][ C1] ret_from_fork+0x1f/0x30 [ 73.877916][ C1] Shutting down cpus with NMI [ 73.884117][ C1] Kernel Offset: disabled [ 73.888437][ C1] Rebooting in 86400 seconds..