[ 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 '10.128.0.126' (ECDSA) to the list of known hosts. 2020/07/23 02:17:12 fuzzer started 2020/07/23 02:17:12 dialing manager at 10.128.0.105:39337 2020/07/23 02:17:13 syscalls: 3213 2020/07/23 02:17:13 code coverage: enabled 2020/07/23 02:17:13 comparison tracing: enabled 2020/07/23 02:17:13 extra coverage: enabled 2020/07/23 02:17:13 setuid sandbox: enabled 2020/07/23 02:17:13 namespace sandbox: enabled 2020/07/23 02:17:13 Android sandbox: /sys/fs/selinux/policy does not exist 2020/07/23 02:17:13 fault injection: enabled 2020/07/23 02:17:13 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2020/07/23 02:17:13 net packet injection: enabled 2020/07/23 02:17:13 net device setup: enabled 2020/07/23 02:17:13 concurrency sanitizer: enabled 2020/07/23 02:17:13 devlink PCI setup: PCI device 0000:00:10.0 is not available 2020/07/23 02:17:13 USB emulation: enabled 2020/07/23 02:17:13 suppressing KCSAN reports in functions: 'ext4_free_inode' '__xa_clear_mark' syzkaller login: [ 34.422941][ T8634] ================================================================== [ 34.431257][ T8634] BUG: KCSAN: data-race in do_epoll_wait / ep_poll_callback [ 34.438780][ T8634] [ 34.441261][ T8634] write to 0xffff888120565110 of 8 bytes by interrupt on cpu 0: [ 34.448973][ T8634] ep_poll_callback+0x29c/0x510 [ 34.453818][ T8634] __wake_up_common+0xbc/0x130 [ 34.458558][ T8634] __wake_up_sync_key+0x83/0xc0 [ 34.465308][ T8634] sock_def_readable+0x61/0xe0 [ 34.470045][ T8634] tcp_rcv_established+0x13c0/0x1520 [ 34.475325][ T8634] tcp_v4_do_rcv+0x25e/0x480 [ 34.479889][ T8634] tcp_v4_rcv+0x219b/0x2420 [ 34.484555][ T8634] ip_protocol_deliver_rcu+0x1f9/0x400 [ 34.489994][ T8634] ip_local_deliver+0x1d6/0x2a0 [ 34.494815][ T8634] ip_sublist_rcv+0x4d4/0x5a0 [ 34.499480][ T8634] ip_list_rcv+0x262/0x290 [ 34.503894][ T8634] __netif_receive_skb_list_core+0x34b/0x450 [ 34.509855][ T8634] __netif_receive_skb_list+0x298/0x310 [ 34.515537][ T8634] netif_receive_skb_list_internal+0xda/0x330 [ 34.522193][ T8634] napi_gro_receive+0x329/0x5a0 [ 34.527110][ T8634] receive_buf+0x7a4/0xcf0 [ 34.531798][ T8634] virtnet_poll+0x2fa/0x780 [ 34.536285][ T8634] napi_poll+0x178/0x4a0 [ 34.540516][ T8634] net_rx_action+0x1ba/0x530 [ 34.545093][ T8634] __do_softirq+0x198/0x360 [ 34.549569][ T8634] asm_call_on_stack+0xf/0x20 [ 34.555015][ T8634] do_softirq_own_stack+0x5d/0x80 [ 34.560552][ T8634] __irq_exit_rcu+0x115/0x120 [ 34.565385][ T8634] common_interrupt+0x14e/0x1e0 [ 34.570301][ T8634] asm_common_interrupt+0x1e/0x40 [ 34.575303][ T8634] native_safe_halt+0xe/0x10 [ 34.579882][ T8634] acpi_idle_enter+0x2ff/0x680 [ 34.584651][ T8634] cpuidle_enter_state+0x245/0x5d0 [ 34.589747][ T8634] cpuidle_enter+0x3c/0x60 [ 34.594151][ T8634] do_idle+0x229/0x310 [ 34.598200][ T8634] cpu_startup_entry+0x15/0x20 [ 34.602968][ T8634] rest_init+0xd8/0xe0 [ 34.607015][ T8634] arch_call_rest_init+0xa/0xb [ 34.611776][ T8634] start_kernel+0x608/0x6d0 [ 34.616252][ T8634] secondary_startup_64+0xa4/0xb0 [ 34.621278][ T8634] [ 34.623607][ T8634] read to 0xffff888120565110 of 8 bytes by task 8634 on cpu 1: [ 34.631230][ T8634] do_epoll_wait+0x2e2/0x870 [ 34.635904][ T8634] __x64_sys_epoll_pwait+0x92/0x150 [ 34.641085][ T8634] do_syscall_64+0x51/0xb0 [ 34.645494][ T8634] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 34.651360][ T8634] [ 34.653670][ T8634] Reported by Kernel Concurrency Sanitizer on: [ 34.659804][ T8634] CPU: 1 PID: 8634 Comm: syz-fuzzer Not tainted 5.8.0-rc6-syzkaller #0 [ 34.668289][ T8634] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 34.678335][ T8634] ================================================================== [ 34.686375][ T8634] Kernel panic - not syncing: panic_on_warn set ... [ 34.692936][ T8634] CPU: 1 PID: 8634 Comm: syz-fuzzer Not tainted 5.8.0-rc6-syzkaller #0 [ 34.701155][ T8634] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 34.711202][ T8634] Call Trace: [ 34.714473][ T8634] dump_stack+0x10f/0x19d [ 34.719148][ T8634] panic+0x207/0x64a [ 34.723023][ T8634] ? vprintk_emit+0x44a/0x4f0 [ 34.727761][ T8634] kcsan_report+0x684/0x690 [ 34.732246][ T8634] ? kcsan_setup_watchpoint+0x453/0x4d0 [ 34.737771][ T8634] ? do_epoll_wait+0x2e2/0x870 [ 34.742510][ T8634] ? __x64_sys_epoll_pwait+0x92/0x150 [ 34.747967][ T8634] ? do_syscall_64+0x51/0xb0 [ 34.752630][ T8634] ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 34.759739][ T8634] ? ep_send_events_proc+0x4fd/0x620 [ 34.765001][ T8634] kcsan_setup_watchpoint+0x453/0x4d0 [ 34.770791][ T8634] do_epoll_wait+0x2e2/0x870 [ 34.775391][ T8634] ? debug_smp_processor_id+0x18/0x20 [ 34.780924][ T8634] __x64_sys_epoll_pwait+0x92/0x150 [ 34.786094][ T8634] do_syscall_64+0x51/0xb0 [ 34.791178][ T8634] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 34.797050][ T8634] RIP: 0033:0x469240 [ 34.800966][ T8634] Code: Bad RIP value. [ 34.805013][ T8634] RSP: 002b:000000c0000777f0 EFLAGS: 00000246 ORIG_RAX: 0000000000000119 [ 34.813418][ T8634] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000469240 [ 34.821801][ T8634] RDX: 0000000000000080 RSI: 000000c000077840 RDI: 0000000000000003 [ 34.829744][ T8634] RBP: 000000c000077e40 R08: 0000000000000000 R09: 0000000000000000 [ 34.837735][ T8634] R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000003 [ 34.845689][ T8634] R13: 000000c000001500 R14: 0000000000000008 R15: 0000000000000004 [ 34.855232][ T8634] Kernel Offset: disabled [ 34.859800][ T8634] Rebooting in 86400 seconds..