[ 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 '10.128.0.41' (ECDSA) to the list of known hosts. 2020/12/12 03:31:13 fuzzer started 2020/12/12 03:31:13 dialing manager at 10.128.0.105:32919 2020/12/12 03:31:13 syscalls: 3464 2020/12/12 03:31:13 code coverage: enabled 2020/12/12 03:31:13 comparison tracing: enabled 2020/12/12 03:31:13 extra coverage: enabled 2020/12/12 03:31:13 setuid sandbox: enabled 2020/12/12 03:31:13 namespace sandbox: enabled 2020/12/12 03:31:13 Android sandbox: /sys/fs/selinux/policy does not exist 2020/12/12 03:31:13 fault injection: enabled 2020/12/12 03:31:13 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2020/12/12 03:31:13 net packet injection: enabled 2020/12/12 03:31:13 net device setup: enabled 2020/12/12 03:31:13 concurrency sanitizer: enabled 2020/12/12 03:31:13 devlink PCI setup: PCI device 0000:00:10.0 is not available 2020/12/12 03:31:13 USB emulation: enabled 2020/12/12 03:31:13 hci packet injection: enabled 2020/12/12 03:31:13 wifi device emulation: enabled 2020/12/12 03:31:17 suppressing KCSAN reports in functions: '__io_cqring_fill_event' '__mark_inode_dirty' 'tick_nohz_stop_tick' 'do_nanosleep' 'isolate_migratepages_block' 'blk_mq_dispatch_rq_list' 'exit_mm' 'xas_find_marked' 'sit_tunnel_xmit' 'do_select' 'blk_mq_sched_dispatch_requests' 'pcpu_alloc' 'do_signal_stop' 'ext4_mb_good_group' 'find_get_pages_range_tag' 'blk_mq_request_bypass_insert' 'alloc_pid' 'ext4_mb_find_by_goal' 'n_tty_receive_buf_common' 'shmem_mknod' 'n_tty_receive_char_inline' 'ext4_writepages' 'shmem_unlink' 'blk_mq_rq_ctx_init' 'audit_log_start' '__filemap_fdatawrite_range' 'complete_signal' 'kauditd_thread' 'wbt_done' 'ext4_handle_inode_extension' 'do_sys_poll' '__ext4_new_inode' 'xas_clear_mark' 'ext4_free_inode' 'dd_has_work' 'expire_timers' 'ext4_free_inodes_count' '__add_to_page_cache_locked' '_prb_read_valid' 'ext4_mb_regular_allocator' 'ext4_mark_iloc_dirty' 'iptunnel_xmit' 'snd_rawmidi_poll' '__xa_clear_mark' 'generic_write_end' '__writeback_single_inode' '__ext4_update_other_inode_time' syzkaller login: [ 45.826953][ T0] ================================================================== [ 45.835981][ T0] BUG: KCSAN: data-race in tick_nohz_next_event / tick_sched_timer [ 45.843872][ T0] [ 45.846196][ T0] write to 0xffffffff86fc1a50 of 4 bytes by interrupt on cpu 1: [ 45.853817][ T0] tick_sched_timer+0x1f5/0x210 [ 45.858676][ T0] __run_hrtimer+0x133/0x420 [ 45.863260][ T0] hrtimer_interrupt+0x36e/0xa10 [ 45.868227][ T0] __sysvec_apic_timer_interrupt+0x6f/0x200 [ 45.874138][ T0] sysvec_apic_timer_interrupt+0x6f/0x90 [ 45.879760][ T0] asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 45.885731][ T0] __tsan_read1+0x12/0x180 [ 45.890228][ T0] ipt_do_table+0x509/0xce0 [ 45.894726][ T0] iptable_mangle_hook+0x13b/0x270 [ 45.899851][ T0] nf_hook_slow_list+0x133/0x340 [ 45.904780][ T0] ip_sublist_rcv+0x56f/0x590 [ 45.909446][ T0] ip_list_rcv+0x262/0x290 [ 45.913854][ T0] __netif_receive_skb_list_core+0x34b/0x450 [ 45.919829][ T0] __netif_receive_skb_list+0x262/0x2e0 [ 45.925369][ T0] netif_receive_skb_list_internal+0xda/0x330 [ 45.931431][ T0] napi_complete_done+0x1b2/0x420 [ 45.936449][ T0] virtqueue_napi_complete+0x28/0x80 [ 45.941723][ T0] virtnet_poll+0x607/0x730 [ 45.946271][ T0] napi_poll+0x178/0x4c0 [ 45.950530][ T0] net_rx_action+0x17a/0x480 [ 45.955103][ T0] __do_softirq+0x12c/0x2b1 [ 45.959648][ T0] asm_call_irq_on_stack+0xf/0x20 [ 45.964813][ T0] do_softirq_own_stack+0x32/0x40 [ 45.969832][ T0] __irq_exit_rcu+0xb2/0xc0 [ 45.974325][ T0] common_interrupt+0xb5/0x130 [ 45.979081][ T0] asm_common_interrupt+0x1e/0x40 [ 45.984121][ T0] [ 45.986539][ T0] read to 0xffffffff86fc1a50 of 4 bytes by task 0 on cpu 0: [ 45.994025][ T0] tick_nohz_next_event+0x217/0x300 [ 45.999249][ T0] tick_nohz_get_sleep_length+0x121/0x270 [ 46.005032][ T0] menu_select+0x2fa/0xf40 [ 46.009450][ T0] cpuidle_select+0x3d/0x50 [ 46.013938][ T0] do_idle+0x15f/0x230 [ 46.017981][ T0] cpu_startup_entry+0x15/0x20 [ 46.022725][ T0] rest_init+0xd7/0xe0 [ 46.026798][ T0] arch_call_rest_init+0xa/0xb [ 46.031594][ T0] start_kernel+0x5a0/0x625 [ 46.036119][ T0] secondary_startup_64_no_verify+0xb0/0xbb [ 46.041998][ T0] [ 46.044310][ T0] Reported by Kernel Concurrency Sanitizer on: [ 46.050451][ T0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.10.0-rc7-syzkaller #0 [ 46.058413][ T0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.068456][ T0] ================================================================== [ 46.076507][ T0] Kernel panic - not syncing: panic_on_warn set ... [ 46.083116][ T0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.10.0-rc7-syzkaller #0 [ 46.091091][ T0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.101173][ T0] Call Trace: [ 46.104466][ T0] dump_stack+0x116/0x15d [ 46.108803][ T0] panic+0x1e7/0x5fa [ 46.112688][ T0] ? vprintk_emit+0x2f2/0x370 [ 46.117380][ T0] kcsan_report+0x67b/0x680 [ 46.121880][ T0] ? kcsan_setup_watchpoint+0x46a/0x4d0 [ 46.127540][ T0] ? tick_nohz_next_event+0x217/0x300 [ 46.132902][ T0] ? tick_nohz_get_sleep_length+0x121/0x270 [ 46.138788][ T0] ? menu_select+0x2fa/0xf40 [ 46.143362][ T0] ? cpuidle_select+0x3d/0x50 [ 46.148026][ T0] ? do_idle+0x15f/0x230 [ 46.152265][ T0] ? cpu_startup_entry+0x15/0x20 [ 46.157192][ T0] ? rest_init+0xd7/0xe0 [ 46.161430][ T0] ? arch_call_rest_init+0xa/0xb [ 46.166364][ T0] ? start_kernel+0x5a0/0x625 [ 46.171020][ T0] ? secondary_startup_64_no_verify+0xb0/0xbb [ 46.177073][ T0] ? ktime_get+0x1b0/0x1e0 [ 46.181479][ T0] ? _raw_spin_lock_irqsave+0x25/0x90 [ 46.186870][ T0] kcsan_setup_watchpoint+0x46a/0x4d0 [ 46.192237][ T0] tick_nohz_next_event+0x217/0x300 [ 46.197492][ T0] tick_nohz_get_sleep_length+0x121/0x270 [ 46.203229][ T0] menu_select+0x2fa/0xf40 [ 46.207634][ T0] ? _raw_spin_unlock_irq+0x22/0x40 [ 46.212843][ T0] ? finish_task_switch+0x81/0x280 [ 46.218129][ T0] cpuidle_select+0x3d/0x50 [ 46.222631][ T0] do_idle+0x15f/0x230 [ 46.226697][ T0] cpu_startup_entry+0x15/0x20 [ 46.231455][ T0] rest_init+0xd7/0xe0 [ 46.235522][ T0] ? time_init+0xc/0xc [ 46.239611][ T0] arch_call_rest_init+0xa/0xb [ 46.244385][ T0] start_kernel+0x5a0/0x625 [ 46.248875][ T0] secondary_startup_64_no_verify+0xb0/0xbb [ 46.255239][ T0] Kernel Offset: disabled [ 46.259553][ T0] Rebooting in 86400 seconds..