[ OK ] Started OpenBSD Secure Shell server. [ 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 '10.128.15.209' (ECDSA) to the list of known hosts. 2020/10/31 03:09:25 fuzzer started 2020/10/31 03:09:25 dialing manager at 10.128.0.105:42145 2020/10/31 03:09:25 syscalls: 3448 2020/10/31 03:09:25 code coverage: enabled 2020/10/31 03:09:25 comparison tracing: enabled 2020/10/31 03:09:25 extra coverage: enabled 2020/10/31 03:09:25 setuid sandbox: enabled 2020/10/31 03:09:25 namespace sandbox: enabled 2020/10/31 03:09:25 Android sandbox: /sys/fs/selinux/policy does not exist 2020/10/31 03:09:25 fault injection: enabled 2020/10/31 03:09:25 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2020/10/31 03:09:25 net packet injection: enabled 2020/10/31 03:09:25 net device setup: enabled 2020/10/31 03:09:25 concurrency sanitizer: enabled 2020/10/31 03:09:25 devlink PCI setup: PCI device 0000:00:10.0 is not available 2020/10/31 03:09:25 USB emulation: enabled 2020/10/31 03:09:25 hci packet injection: enabled 2020/10/31 03:09:25 wifi device emulation: enabled 2020/10/31 03:09:31 suppressing KCSAN reports in functions: 'inc_node_page_state' 'blk_mq_rq_ctx_init' 'ext4_free_inode' 'pcpu_alloc' '__mark_inode_dirty' 'generic_file_buffered_read' 'find_get_pages_range_tag' 'do_nanosleep' 'ext4_setattr' 'blk_mq_sched_dispatch_requests' 'generic_write_end' 'complete_signal' 'do_sys_poll' 'futex_wait_queue_me' 'ext4_writepages' '__ext4_new_inode' '__io_cqring_fill_event' 'n_tty_receive_buf_common' 'exit_mm' 'snd_rawmidi_poll' 'do_select' '__xa_clear_mark' 'xas_find_marked' '_prb_read_valid' '__ptrace_unlink' 'audit_log_start' '__ext4_update_other_inode_time' 'wbt_wait' 'ext4_free_inodes_count' '__xa_set_mark' 'wbt_issue' 'snd_rawmidi_transmit' 'kauditd_thread' 'shmem_unlink' '__io_async_wake' 'dd_has_work' 'wbt_done' 'ext4_mark_iloc_dirty' '__delete_from_page_cache' 'expire_timers' '__send_signal' 'add_input_randomness' 'blk_mq_dispatch_rq_list' 'ext4_sync_file' 'do_signal_stop' 'ext4_mb_regular_allocator' 'get_cpu_idle_time_us' 'alloc_pid' 'xas_clear_mark' 'ext4_mb_good_group' 'snd_rawmidi_kernel_write1' 'do_readlinkat' syzkaller login: [ 61.086093][ T0] ================================================================== [ 61.094224][ T0] BUG: KCSAN: data-race in tick_nohz_next_event / tick_sched_timer [ 61.102123][ T0] [ 61.104447][ T0] write to 0xffffffff86fc2bd0 of 4 bytes by interrupt on cpu 1: [ 61.112079][ T0] tick_sched_timer+0x1f5/0x210 [ 61.116930][ T0] __run_hrtimer+0x133/0x420 [ 61.121523][ T0] hrtimer_interrupt+0x36e/0xa10 [ 61.126480][ T0] __sysvec_apic_timer_interrupt+0x6f/0x200 [ 61.132506][ T0] sysvec_apic_timer_interrupt+0x6f/0x90 [ 61.138125][ T0] asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 61.144082][ T0] [ 61.146515][ T0] read to 0xffffffff86fc2bd0 of 4 bytes by task 0 on cpu 0: [ 61.153833][ T0] tick_nohz_next_event+0x217/0x300 [ 61.159025][ T0] tick_nohz_get_sleep_length+0x121/0x270 [ 61.164738][ T0] menu_select+0x2fa/0xf40 [ 61.169160][ T0] cpuidle_select+0x3d/0x50 [ 61.173657][ T0] do_idle+0x15f/0x230 [ 61.177733][ T0] cpu_startup_entry+0x15/0x20 [ 61.182492][ T0] rest_init+0xd7/0xe0 [ 61.186646][ T0] arch_call_rest_init+0xa/0xb [ 61.191404][ T0] start_kernel+0x5a0/0x625 [ 61.195902][ T0] secondary_startup_64_no_verify+0xa6/0xab [ 61.201781][ T0] [ 61.204101][ T0] Reported by Kernel Concurrency Sanitizer on: [ 61.210249][ T0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.10.0-rc1-syzkaller #0 [ 61.218733][ T0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.228787][ T0] ================================================================== [ 61.236871][ T0] Kernel panic - not syncing: panic_on_warn set ... [ 61.243465][ T0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.10.0-rc1-syzkaller #0 [ 61.251431][ T0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.261578][ T0] Call Trace: [ 61.264896][ T0] dump_stack+0x116/0x15d [ 61.269925][ T0] panic+0x1e7/0x5fa [ 61.273822][ T0] ? vprintk_emit+0x2f2/0x370 [ 61.278505][ T0] kcsan_report+0x67b/0x680 [ 61.283026][ T0] ? kcsan_setup_watchpoint+0x46a/0x4d0 [ 61.288560][ T0] ? tick_nohz_next_event+0x217/0x300 [ 61.293934][ T0] ? tick_nohz_get_sleep_length+0x121/0x270 [ 61.299832][ T0] ? menu_select+0x2fa/0xf40 [ 61.304435][ T0] ? cpuidle_select+0x3d/0x50 [ 61.309111][ T0] ? do_idle+0x15f/0x230 [ 61.313352][ T0] ? cpu_startup_entry+0x15/0x20 [ 61.318287][ T0] ? rest_init+0xd7/0xe0 [ 61.323486][ T0] ? arch_call_rest_init+0xa/0xb [ 61.328429][ T0] ? start_kernel+0x5a0/0x625 [ 61.333112][ T0] ? secondary_startup_64_no_verify+0xa6/0xab [ 61.339190][ T0] ? ktime_get+0x1b0/0x1e0 [ 61.343635][ T0] ? _raw_spin_lock_irqsave+0x25/0x90 [ 61.349003][ T0] kcsan_setup_watchpoint+0x46a/0x4d0 [ 61.354369][ T0] tick_nohz_next_event+0x217/0x300 [ 61.359559][ T0] tick_nohz_get_sleep_length+0x121/0x270 [ 61.365288][ T0] menu_select+0x2fa/0xf40 [ 61.369711][ T0] ? _raw_spin_unlock_irq+0x22/0x40 [ 61.375344][ T0] ? finish_task_switch+0x81/0x280 [ 61.380458][ T0] cpuidle_select+0x3d/0x50 [ 61.384957][ T0] do_idle+0x15f/0x230 [ 61.389036][ T0] cpu_startup_entry+0x15/0x20 [ 61.393796][ T0] rest_init+0xd7/0xe0 [ 61.397865][ T0] ? time_init+0xc/0xc [ 61.401924][ T0] arch_call_rest_init+0xa/0xb [ 61.406676][ T0] start_kernel+0x5a0/0x625 [ 61.411304][ T0] secondary_startup_64_no_verify+0xa6/0xab [ 61.417750][ T0] Kernel Offset: disabled [ 61.422063][ T0] Rebooting in 86400 seconds..