[ OK ] Started System Logging Service. [ 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 '10.128.0.203' (ECDSA) to the list of known hosts. 2020/07/24 17:23:52 fuzzer started 2020/07/24 17:23:52 dialing manager at 10.128.0.105:33633 2020/07/24 17:23:52 syscalls: 3213 2020/07/24 17:23:52 code coverage: enabled 2020/07/24 17:23:52 comparison tracing: enabled 2020/07/24 17:23:52 extra coverage: enabled 2020/07/24 17:23:52 setuid sandbox: enabled 2020/07/24 17:23:52 namespace sandbox: enabled 2020/07/24 17:23:52 Android sandbox: /sys/fs/selinux/policy does not exist 2020/07/24 17:23:52 fault injection: enabled 2020/07/24 17:23:52 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2020/07/24 17:23:52 net packet injection: enabled 2020/07/24 17:23:52 net device setup: enabled 2020/07/24 17:23:52 concurrency sanitizer: enabled 2020/07/24 17:23:52 devlink PCI setup: PCI device 0000:00:10.0 is not available 2020/07/24 17:23:52 USB emulation: enabled 2020/07/24 17:23:55 suppressing KCSAN reports in functions: 'n_tty_receive_buf_common' 'page_counter_charge' 'blk_mq_rq_ctx_init' 'do_syslog' '__add_to_page_cache_locked' 'tick_sched_timer' 'wbt_issue' 'find_get_pages_range_tag' 'ext4_writepages' 'dec_zone_page_state' 'xas_find_marked' 'xas_clear_mark' 'ext4_free_inodes_count' 'do_sys_poll' 'ext4_mb_regular_allocator' 'futex_wait_queue_me' 'dput' 'do_epoll_wait' 'do_nanosleep' 'padata_reorder' 'alloc_pid' 'shmem_add_to_page_cache' 'wg_packet_decrypt_worker' 'ext4_mark_iloc_dirty' '__ext4_new_inode' 'do_signal_stop' '__xa_clear_mark' 'generic_write_end' 'ext4_ext_insert_extent' 'audit_log_start' '__ext4_update_other_inode_time' 'filemap_map_pages' 'dd_has_work' 'ext4_free_inode' 'ext4_sync_file' '__delayacct_blkio_end' 'do_readlinkat' 'blk_mq_sched_dispatch_requests' 'pcpu_alloc' 'snd_rawmidi_poll' 'blk_mq_request_bypass_insert' 'kauditd_thread' '__mod_timer' 'expire_timers' 'blk_mq_dispatch_rq_list' 'exit_mm' 'do_select' syzkaller login: [ 103.745346][ C0] ================================================================== [ 103.753485][ C0] BUG: KCSAN: data-race in add_timer_on / timer_clear_idle [ 103.760643][ C0] [ 103.763051][ C0] write to 0xffff88812c11cb24 of 1 bytes by task 0 on cpu 1: [ 103.770462][ C0] timer_clear_idle+0x2e/0x40 [ 103.775112][ C0] tick_nohz_idle_retain_tick+0x3e/0x40 [ 103.780625][ C0] do_idle+0x287/0x310 [ 103.784662][ C0] cpu_startup_entry+0x15/0x20 [ 103.789396][ C0] start_secondary+0xe3/0x110 [ 103.794041][ C0] secondary_startup_64+0xa4/0xb0 [ 103.799076][ C0] [ 103.801374][ C0] read to 0xffff88812c11cb24 of 1 bytes by interrupt on cpu 0: [ 103.809006][ C0] add_timer_on+0x2f9/0x3b0 [ 103.813480][ C0] clocksource_watchdog+0x729/0x760 [ 103.818649][ C0] call_timer_fn+0x30/0x2a0 [ 103.823120][ C0] expire_timers+0x116/0x290 [ 103.827676][ C0] __run_timers+0x443/0x500 [ 103.832236][ C0] run_timer_softirq+0x2e/0x60 [ 103.836979][ C0] __do_softirq+0x198/0x360 [ 103.841450][ C0] asm_call_on_stack+0xf/0x20 [ 103.846093][ C0] do_softirq_own_stack+0x5d/0x80 [ 103.851084][ C0] __irq_exit_rcu+0x115/0x120 [ 103.855751][ C0] sysvec_apic_timer_interrupt+0xba/0xd0 [ 103.861362][ C0] asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 103.867306][ C0] [ 103.869620][ C0] Reported by Kernel Concurrency Sanitizer on: [ 103.875743][ C0] CPU: 0 PID: 8630 Comm: syz-fuzzer Not tainted 5.8.0-rc6-syzkaller #0 [ 103.883955][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 103.893978][ C0] ================================================================== [ 103.902012][ C0] Kernel panic - not syncing: panic_on_warn set ... [ 103.908578][ C0] CPU: 0 PID: 8630 Comm: syz-fuzzer Not tainted 5.8.0-rc6-syzkaller #0 [ 103.916781][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 103.926898][ C0] Call Trace: [ 103.930152][ C0] [ 103.932976][ C0] dump_stack+0x10f/0x19d [ 103.937271][ C0] panic+0x207/0x64a [ 103.941149][ C0] ? vprintk_emit+0x44a/0x4f0 [ 103.945799][ C0] kcsan_report+0x684/0x690 [ 103.950288][ C0] ? kcsan_setup_watchpoint+0x453/0x4d0 [ 103.955802][ C0] ? add_timer_on+0x2f9/0x3b0 [ 103.960447][ C0] ? clocksource_watchdog+0x729/0x760 [ 103.965783][ C0] ? call_timer_fn+0x30/0x2a0 [ 103.970513][ C0] ? expire_timers+0x116/0x290 [ 103.975240][ C0] ? __run_timers+0x443/0x500 [ 103.979886][ C0] ? run_timer_softirq+0x2e/0x60 [ 103.984804][ C0] ? __do_softirq+0x198/0x360 [ 103.989447][ C0] ? asm_call_on_stack+0xf/0x20 [ 103.994271][ C0] ? do_softirq_own_stack+0x5d/0x80 [ 103.999522][ C0] ? __irq_exit_rcu+0x115/0x120 [ 104.004360][ C0] ? sysvec_apic_timer_interrupt+0xba/0xd0 [ 104.010141][ C0] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 104.016324][ C0] ? __internal_add_timer+0x27c/0x360 [ 104.021684][ C0] ? __internal_add_timer+0x27c/0x360 [ 104.027042][ C0] kcsan_setup_watchpoint+0x453/0x4d0 [ 104.032384][ C0] ? __internal_add_timer+0x27c/0x360 [ 104.037722][ C0] add_timer_on+0x2f9/0x3b0 [ 104.042205][ C0] clocksource_watchdog+0x729/0x760 [ 104.047373][ C0] ? __clocksource_select+0x340/0x340 [ 104.052712][ C0] call_timer_fn+0x30/0x2a0 [ 104.057182][ C0] ? __clocksource_select+0x340/0x340 [ 104.062523][ C0] expire_timers+0x116/0x290 [ 104.067084][ C0] __run_timers+0x443/0x500 [ 104.071571][ C0] ? __kfree_skb_flush+0x7e/0xa0 [ 104.076475][ C0] ? kvm_sched_clock_read+0x15/0x40 [ 104.081643][ C0] run_timer_softirq+0x2e/0x60 [ 104.086376][ C0] __do_softirq+0x198/0x360 [ 104.090854][ C0] ? asm_sysvec_apic_timer_interrupt+0xa/0x20 [ 104.096905][ C0] asm_call_on_stack+0xf/0x20 [ 104.101548][ C0] [ 104.104469][ C0] do_softirq_own_stack+0x5d/0x80 [ 104.109463][ C0] __irq_exit_rcu+0x115/0x120 [ 104.122275][ C0] sysvec_apic_timer_interrupt+0xba/0xd0 [ 104.127876][ C0] asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 104.133835][ C0] RIP: 0033:0x4107fb [ 104.137693][ C0] Code: Bad RIP value. [ 104.141738][ C0] RSP: 002b:000000c00f49f7f0 EFLAGS: 00000246 [ 104.147873][ C0] RAX: 000000c0069252c0 RBX: 000000006fcfd877 RCX: 000000c0069252c8 [ 104.155814][ C0] RDX: 0000000000000000 RSI: 00000000008e4ea0 RDI: 0000000000000038 [ 104.163756][ C0] RBP: 000000c00f49f808 R08: 0000000000000000 R09: 000000c00202225b [ 104.171703][ C0] R10: 0000000000000001 R11: ffffffffffffffff R12: 0000000000000003 [ 104.179644][ C0] R13: 0000000000000023 R14: 000000000000000b R15: ffffffffffffffff [ 105.302489][ C0] Shutting down cpus with NMI [ 105.308552][ C0] Kernel Offset: disabled [ 105.312884][ C0] Rebooting in 86400 seconds..