[ 43.690876][ T8830] bash (8830) used greatest stack depth: 10456 bytes left [ OK ] Started Getty on tty2. [ OK ] Started Getty on tty1. [ OK ] Started Serial Getty on ttyS0. [ 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. Starting Load/Save RF Kill Switch Status... [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.1.3' (ECDSA) to the list of known hosts. 2020/06/04 13:48:36 fuzzer started 2020/06/04 13:48:37 dialing manager at 10.128.0.105:43989 2020/06/04 13:48:37 syscalls: 3055 2020/06/04 13:48:37 code coverage: enabled 2020/06/04 13:48:37 comparison tracing: enabled 2020/06/04 13:48:37 extra coverage: enabled 2020/06/04 13:48:37 setuid sandbox: enabled 2020/06/04 13:48:37 namespace sandbox: enabled 2020/06/04 13:48:37 Android sandbox: /sys/fs/selinux/policy does not exist 2020/06/04 13:48:37 fault injection: enabled 2020/06/04 13:48:37 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2020/06/04 13:48:37 net packet injection: enabled 2020/06/04 13:48:37 net device setup: enabled 2020/06/04 13:48:37 concurrency sanitizer: enabled 2020/06/04 13:48:37 devlink PCI setup: PCI device 0000:00:10.0 is not available 2020/06/04 13:48:37 USB emulation: enabled syzkaller login: [ 52.306224][ T8942] KCSAN: could not find function: '_find_next_bit' 2020/06/04 13:48:40 adding functions to KCSAN blacklist: '_find_next_bit' 'run_timer_softirq' 'do_nanosleep' 'page_counter_charge' 'find_get_pages_range_tag' 'generic_fillattr' 'complete_signal' 'add_timer' '__send_signal' 'ep_poll' 'snd_rawmidi_kernel_write1' 'kauditd_thread' 'dd_has_work' 'copy_process' 'generic_write_end' 'blk_mq_dispatch_rq_list' 'xas_clear_mark' 'pcpu_alloc' '__ext4_new_inode' 'mod_timer' 'tick_nohz_next_event' 'echo_char' [ 81.798874][ T0] ================================================================== [ 81.807134][ T0] BUG: KCSAN: data-race in tick_nohz_idle_stop_tick / tick_sched_do_timer [ 81.815622][ T0] [ 81.817981][ T0] write to 0xffffffff8764e210 of 4 bytes by interrupt on cpu 0: [ 81.825618][ T0] tick_sched_do_timer+0xb4/0xd0 [ 81.830579][ T0] tick_sched_timer+0x3f/0xd0 [ 81.835260][ T0] __hrtimer_run_queues+0x271/0x600 [ 81.840568][ T0] hrtimer_interrupt+0x226/0x490 [ 81.845516][ T0] smp_apic_timer_interrupt+0xd8/0x270 [ 81.851118][ T0] apic_timer_interrupt+0xf/0x20 [ 81.856096][ T0] __tsan_unaligned_write4+0x30/0x110 [ 81.861479][ T0] ip_finish_output2+0x1d9/0xed0 [ 81.866446][ T0] __ip_finish_output+0x22f/0x460 [ 81.871735][ T0] ip_finish_output+0x3e/0x160 [ 81.876619][ T0] ip_output+0xf2/0x240 [ 81.880787][ T0] ip_local_out+0x70/0x90 [ 81.885156][ T0] __ip_queue_xmit+0x3a6/0xa40 [ 81.889927][ T0] ip_queue_xmit+0x3e/0x50 [ 81.894380][ T0] __tcp_transmit_skb+0xe0c/0x1d80 [ 81.899502][ T0] __tcp_send_ack+0x22c/0x2f0 [ 81.904186][ T0] tcp_send_ack+0x2d/0x40 [ 81.908515][ T0] tcp_cleanup_rbuf+0x124/0x340 [ 81.913368][ T0] tcp_recvmsg+0x686/0x1ba0 [ 81.917880][ T0] inet_recvmsg+0xc1/0x250 [ 81.922313][ T0] sock_recvmsg+0x8e/0xb0 [ 81.926645][ T0] sock_read_iter+0x185/0x230 [ 81.931354][ T0] new_sync_read+0x416/0x450 [ 81.935949][ T0] __vfs_read+0x9e/0xb0 [ 81.940162][ T0] vfs_read+0x13e/0x2b0 [ 81.944320][ T0] ksys_read+0x16a/0x1a0 [ 81.948566][ T0] __x64_sys_read+0x49/0x60 [ 81.953081][ T0] do_syscall_64+0xc7/0x3b0 [ 81.957622][ T0] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 81.963516][ T0] [ 81.965850][ T0] read to 0xffffffff8764e210 of 4 bytes by task 0 on cpu 1: [ 81.973142][ T0] tick_nohz_idle_stop_tick+0x191/0x680 [ 81.979223][ T0] do_idle+0x1ad/0x290 [ 81.983299][ T0] cpu_startup_entry+0x14/0x20 [ 81.988199][ T0] start_secondary+0x169/0x1b0 [ 81.993009][ T0] secondary_startup_64+0xa4/0xb0 [ 81.998021][ T0] [ 82.000339][ T0] Reported by Kernel Concurrency Sanitizer on: [ 82.007031][ T0] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.7.0-rc1-syzkaller #0 [ 82.014911][ T0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 82.024963][ T0] ================================================================== [ 82.033024][ T0] Kernel panic - not syncing: panic_on_warn set ... [ 82.039635][ T0] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.7.0-rc1-syzkaller #0 [ 82.047522][ T0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 82.057692][ T0] Call Trace: [ 82.060999][ T0] dump_stack+0x11d/0x187 [ 82.065340][ T0] panic+0x210/0x640 [ 82.069242][ T0] ? vprintk_func+0x89/0x13a [ 82.073836][ T0] kcsan_report.cold+0xc/0x1a [ 82.078533][ T0] kcsan_setup_watchpoint+0x3fb/0x440 [ 82.083926][ T0] tick_nohz_idle_stop_tick+0x191/0x680 [ 82.089487][ T0] do_idle+0x1ad/0x290 [ 82.093830][ T0] cpu_startup_entry+0x14/0x20 [ 82.098600][ T0] start_secondary+0x169/0x1b0 [ 82.103459][ T0] secondary_startup_64+0xa4/0xb0 [ 82.109993][ T0] Kernel Offset: disabled [ 82.114311][ T0] Rebooting in 86400 seconds..