[ 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 '10.128.10.16' (ECDSA) to the list of known hosts. 2020/08/01 03:15:25 fuzzer started 2020/08/01 03:15:25 dialing manager at 10.128.0.105:34355 2020/08/01 03:15:26 syscalls: 3254 2020/08/01 03:15:26 code coverage: enabled 2020/08/01 03:15:26 comparison tracing: enabled 2020/08/01 03:15:26 extra coverage: enabled 2020/08/01 03:15:26 setuid sandbox: enabled 2020/08/01 03:15:26 namespace sandbox: enabled 2020/08/01 03:15:26 Android sandbox: /sys/fs/selinux/policy does not exist 2020/08/01 03:15:26 fault injection: enabled 2020/08/01 03:15:26 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2020/08/01 03:15:26 net packet injection: enabled 2020/08/01 03:15:26 net device setup: enabled 2020/08/01 03:15:26 concurrency sanitizer: enabled 2020/08/01 03:15:26 devlink PCI setup: PCI device 0000:00:10.0 is not available 2020/08/01 03:15:26 USB emulation: enabled 2020/08/01 03:15:26 hci packet injection: enabled 2020/08/01 03:15:26 suppressing KCSAN reports in functions: 'generic_write_end' 'exit_mm' '__ext4_update_other_inode_time' 'generic_file_buffered_read' 'do_select' 'ext4_free_inode' '__delayacct_blkio_end' 'blk_mq_request_bypass_insert' 'alloc_pid' 'ext4_free_inodes_count' '__ext4_new_inode' '__xa_clear_mark' 'blk_mq_sched_dispatch_requests' 'ext4_writepages' syzkaller login: [ 31.084621][ T8640] ================================================================== [ 31.092724][ T8640] BUG: KCSAN: data-race in do_epoll_wait / ep_poll_callback [ 31.099977][ T8640] [ 31.102280][ T8640] write to 0xffff8881245ef290 of 8 bytes by interrupt on cpu 1: [ 31.109870][ T8640] ep_poll_callback+0x29c/0x510 [ 31.114684][ T8640] __wake_up_common+0xbc/0x130 [ 31.119412][ T8640] __wake_up_sync_key+0x83/0xc0 [ 31.124224][ T8640] sock_def_readable+0x61/0xe0 [ 31.128998][ T8640] tcp_rcv_established+0x13c0/0x1520 [ 31.134249][ T8640] tcp_v4_do_rcv+0x25e/0x480 [ 31.138804][ T8640] tcp_v4_rcv+0x219b/0x2420 [ 31.143270][ T8640] ip_protocol_deliver_rcu+0x1f9/0x400 [ 31.148709][ T8640] ip_local_deliver+0x1d6/0x2a0 [ 31.153559][ T8640] ip_sublist_rcv+0x4d4/0x5a0 [ 31.158197][ T8640] ip_list_rcv+0x262/0x290 [ 31.162575][ T8640] __netif_receive_skb_list_core+0x34b/0x450 [ 31.168521][ T8640] __netif_receive_skb_list+0x298/0x310 [ 31.174120][ T8640] netif_receive_skb_list_internal+0xda/0x330 [ 31.180159][ T8640] napi_gro_receive+0x329/0x5a0 [ 31.184992][ T8640] receive_buf+0x7a4/0xcf0 [ 31.189385][ T8640] virtnet_poll+0x2fa/0x780 [ 31.193849][ T8640] napi_poll+0x178/0x4a0 [ 31.198078][ T8640] net_rx_action+0x1ba/0x530 [ 31.202630][ T8640] __do_softirq+0x198/0x360 [ 31.207095][ T8640] run_ksoftirqd+0x2f/0x60 [ 31.211474][ T8640] smpboot_thread_fn+0x347/0x530 [ 31.216376][ T8640] kthread+0x20d/0x230 [ 31.220415][ T8640] ret_from_fork+0x1f/0x30 [ 31.224792][ T8640] [ 31.227090][ T8640] read to 0xffff8881245ef290 of 8 bytes by task 8640 on cpu 0: [ 31.234597][ T8640] do_epoll_wait+0x2e2/0x870 [ 31.239154][ T8640] __x64_sys_epoll_pwait+0x92/0x150 [ 31.244329][ T8640] do_syscall_64+0x51/0xb0 [ 31.248714][ T8640] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 31.254562][ T8640] [ 31.256853][ T8640] Reported by Kernel Concurrency Sanitizer on: [ 31.262985][ T8640] CPU: 0 PID: 8640 Comm: syz-fuzzer Not tainted 5.8.0-rc7-syzkaller #0 [ 31.271181][ T8640] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.281198][ T8640] ================================================================== [ 31.289221][ T8640] Kernel panic - not syncing: panic_on_warn set ... [ 31.295880][ T8640] CPU: 0 PID: 8640 Comm: syz-fuzzer Not tainted 5.8.0-rc7-syzkaller #0 [ 31.304076][ T8640] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.314095][ T8640] Call Trace: [ 31.317352][ T8640] dump_stack+0x10f/0x19d [ 31.321658][ T8640] panic+0x207/0x64a [ 31.325519][ T8640] ? vprintk_emit+0x44a/0x4f0 [ 31.330165][ T8640] kcsan_report+0x684/0x690 [ 31.334634][ T8640] ? kcsan_setup_watchpoint+0x453/0x4d0 [ 31.340173][ T8640] ? do_epoll_wait+0x2e2/0x870 [ 31.344902][ T8640] ? __x64_sys_epoll_pwait+0x92/0x150 [ 31.350237][ T8640] ? do_syscall_64+0x51/0xb0 [ 31.354791][ T8640] ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 31.360826][ T8640] ? ep_send_events_proc+0x4fd/0x620 [ 31.366096][ T8640] kcsan_setup_watchpoint+0x453/0x4d0 [ 31.371434][ T8640] do_epoll_wait+0x2e2/0x870 [ 31.376004][ T8640] ? debug_smp_processor_id+0x18/0x20 [ 31.381337][ T8640] __x64_sys_epoll_pwait+0x92/0x150 [ 31.386500][ T8640] do_syscall_64+0x51/0xb0 [ 31.390879][ T8640] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 31.396732][ T8640] RIP: 0033:0x469240 [ 31.400593][ T8640] Code: 0f 05 89 44 24 20 c3 cc cc cc 8b 7c 24 08 48 8b 74 24 10 8b 54 24 18 44 8b 54 24 1c 49 c7 c0 00 00 00 00 b8 19 01 00 00 0f 05 <89> 44 24 20 c3 cc cc cc cc cc cc cc cc cc cc cc 8b 7c 24 08 48 c7 [ 31.420160][ T8640] RSP: 002b:000000c00004f7f0 EFLAGS: 00000246 ORIG_RAX: 0000000000000119 [ 31.428532][ T8640] RAX: ffffffffffffffda RBX: 000000000000016f RCX: 0000000000469240 [ 31.436501][ T8640] RDX: 0000000000000080 RSI: 000000c00004f840 RDI: 0000000000000003 [ 31.444438][ T8640] RBP: 000000c00004fe40 R08: 0000000000000000 R09: 0000000000000000 [ 31.452378][ T8640] R10: 000000000000016f R11: 0000000000000246 R12: 0000000000000003 [ 31.460320][ T8640] R13: 000000c000000900 R14: 0000000000000002 R15: 0000000000000002 [ 31.469339][ T8640] Kernel Offset: disabled [ 31.473644][ T8640] Rebooting in 86400 seconds..