[ 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 '10.128.0.121' (ECDSA) to the list of known hosts. 2020/06/07 09:03:29 fuzzer started 2020/06/07 09:03:29 dialing manager at 10.128.0.105:43689 2020/06/07 09:03:30 syscalls: 3055 2020/06/07 09:03:30 code coverage: enabled 2020/06/07 09:03:30 comparison tracing: enabled 2020/06/07 09:03:30 extra coverage: enabled 2020/06/07 09:03:30 setuid sandbox: enabled 2020/06/07 09:03:30 namespace sandbox: enabled 2020/06/07 09:03:30 Android sandbox: /sys/fs/selinux/policy does not exist 2020/06/07 09:03:30 fault injection: enabled 2020/06/07 09:03:30 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2020/06/07 09:03:30 net packet injection: enabled 2020/06/07 09:03:30 net device setup: enabled 2020/06/07 09:03:30 concurrency sanitizer: enabled 2020/06/07 09:03:30 devlink PCI setup: PCI device 0000:00:10.0 is not available 2020/06/07 09:03:30 USB emulation: enabled 2020/06/07 09:03:31 adding functions to KCSAN blacklist: 'wbt_done' 'add_timer' 'generic_write_end' 'blk_mq_dispatch_rq_list' 'ep_poll' 'find_get_pages_range_tag' 'run_timer_softirq' '__snd_rawmidi_transmit_ack' syzkaller login: [ 62.648759][ T0] ================================================================== [ 62.657074][ T0] BUG: KCSAN: data-race in tick_nohz_next_event / tick_sched_do_timer [ 62.665223][ T0] [ 62.668305][ T0] write to 0xffffffff8764e210 of 4 bytes by interrupt on cpu 1: [ 62.675940][ T0] tick_sched_do_timer+0xb4/0xd0 [ 62.680876][ T0] tick_sched_timer+0x3f/0xd0 [ 62.685547][ T0] __hrtimer_run_queues+0x271/0x600 [ 62.690748][ T0] hrtimer_interrupt+0x226/0x490 [ 62.695698][ T0] smp_apic_timer_interrupt+0xd8/0x270 [ 62.701155][ T0] apic_timer_interrupt+0xf/0x20 [ 62.706181][ T0] write_comp_data+0x0/0x70 [ 62.710687][ T0] __sanitizer_cov_trace_switch+0x45/0x70 [ 62.716410][ T0] __read_once_size+0x20/0x100 [ 62.721181][ T0] __netif_receive_skb_core+0x1786/0x2120 [ 62.726899][ T0] __netif_receive_skb_list_core+0x2b1/0x5c0 [ 62.732882][ T0] netif_receive_skb_list_internal+0x5c7/0x810 [ 62.739045][ T0] gro_normal_list.part.0+0x37/0xa0 [ 62.744353][ T0] gro_normal_one+0x14c/0x160 [ 62.749032][ T0] napi_gro_receive+0x27d/0x2f0 [ 62.753886][ T0] receive_buf+0x24c/0x3420 [ 62.758391][ T0] virtnet_poll+0x343/0x790 [ 62.762923][ T0] net_rx_action+0x3ad/0xac0 [ 62.767628][ T0] __do_softirq+0x118/0x34a [ 62.772127][ T0] irq_exit+0xb5/0xd0 [ 62.776102][ T0] do_IRQ+0x7b/0x120 [ 62.779994][ T0] ret_from_intr+0x0/0x21 [ 62.784331][ T0] __tsan_read2+0xe4/0x110 [ 62.788748][ T0] ipt_do_table+0x112/0xe70 [ 62.793251][ T0] iptable_raw_hook+0x44/0x60 [ 62.798115][ T0] nf_hook_slow+0x7c/0x160 [ 62.802535][ T0] __ip_local_out+0x1f3/0x2b0 [ 62.807568][ T0] ip_local_out+0x2d/0x90 [ 62.811886][ T0] __ip_queue_xmit+0x3a6/0xa40 [ 62.816635][ T0] ip_queue_xmit+0x3e/0x50 [ 62.821675][ T0] __tcp_transmit_skb+0xe0c/0x1d80 [ 62.826872][ T0] __tcp_send_ack+0x22c/0x2f0 [ 62.831542][ T0] tcp_send_ack+0x2d/0x40 [ 62.835859][ T0] tcp_cleanup_rbuf+0x124/0x340 [ 62.840804][ T0] tcp_recvmsg+0x686/0x1ba0 [ 62.845308][ T0] inet_recvmsg+0xc1/0x250 [ 62.849720][ T0] sock_recvmsg+0x8e/0xb0 [ 62.854062][ T0] sock_read_iter+0x185/0x230 [ 62.858749][ T0] new_sync_read+0x416/0x450 [ 62.863328][ T0] __vfs_read+0x9e/0xb0 [ 62.867480][ T0] vfs_read+0x13e/0x2b0 [ 62.871624][ T0] ksys_read+0x16a/0x1a0 [ 62.875862][ T0] __x64_sys_read+0x49/0x60 [ 62.880363][ T0] do_syscall_64+0xc7/0x3b0 [ 62.884947][ T0] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 62.890829][ T0] [ 62.893141][ T0] read to 0xffffffff8764e210 of 4 bytes by task 0 on cpu 0: [ 62.900478][ T0] tick_nohz_next_event+0x181/0x340 [ 62.905696][ T0] tick_nohz_idle_stop_tick+0x3b9/0x680 [ 62.911349][ T0] do_idle+0x1ad/0x290 [ 62.915513][ T0] cpu_startup_entry+0x14/0x20 [ 62.920256][ T0] rest_init+0xe4/0xeb [ 62.924484][ T0] arch_call_rest_init+0x13/0x2b [ 62.929569][ T0] start_kernel+0x7fe/0x823 [ 62.934100][ T0] secondary_startup_64+0xa4/0xb0 [ 62.939264][ T0] [ 62.941585][ T0] Reported by Kernel Concurrency Sanitizer on: [ 62.947727][ T0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-rc1-syzkaller #0 [ 62.955981][ T0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.966821][ T0] ================================================================== [ 62.974871][ T0] Kernel panic - not syncing: panic_on_warn set ... [ 62.981494][ T0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-rc1-syzkaller #0 [ 62.989498][ T0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.999674][ T0] Call Trace: [ 63.002960][ T0] dump_stack+0x11d/0x187 [ 63.007304][ T0] panic+0x210/0x640 [ 63.011202][ T0] ? vprintk_func+0x89/0x13a [ 63.015792][ T0] kcsan_report.cold+0xc/0x1a [ 63.020823][ T0] kcsan_setup_watchpoint+0x3fb/0x440 [ 63.026184][ T0] tick_nohz_next_event+0x181/0x340 [ 63.031382][ T0] tick_nohz_idle_stop_tick+0x3b9/0x680 [ 63.036935][ T0] ? ktime_get+0x1c9/0x210 [ 63.041743][ T0] ? debug_smp_processor_id+0x3f/0x129 [ 63.047202][ T0] do_idle+0x1ad/0x290 [ 63.051265][ T0] ? debug_smp_processor_id+0x3f/0x129 [ 63.056715][ T0] cpu_startup_entry+0x14/0x20 [ 63.061507][ T0] rest_init+0xe4/0xeb [ 63.065574][ T0] ? trace_init_perf_perm_irq_work_exit+0xe/0xe [ 63.071804][ T0] arch_call_rest_init+0x13/0x2b [ 63.076845][ T0] start_kernel+0x7fe/0x823 [ 63.081353][ T0] secondary_startup_64+0xa4/0xb0 [ 63.088143][ T0] Kernel Offset: disabled [ 63.092560][ T0] Rebooting in 86400 seconds..