[ 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 '10.128.0.250' (ECDSA) to the list of known hosts. 2020/11/04 06:03:33 fuzzer started 2020/11/04 06:03:33 dialing manager at 10.128.0.105:36273 2020/11/04 06:03:34 syscalls: 3448 2020/11/04 06:03:34 code coverage: enabled 2020/11/04 06:03:34 comparison tracing: enabled 2020/11/04 06:03:34 extra coverage: enabled 2020/11/04 06:03:34 setuid sandbox: enabled 2020/11/04 06:03:34 namespace sandbox: enabled 2020/11/04 06:03:34 Android sandbox: /sys/fs/selinux/policy does not exist 2020/11/04 06:03:34 fault injection: enabled 2020/11/04 06:03:34 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2020/11/04 06:03:34 net packet injection: enabled 2020/11/04 06:03:34 net device setup: enabled 2020/11/04 06:03:34 concurrency sanitizer: enabled 2020/11/04 06:03:34 devlink PCI setup: PCI device 0000:00:10.0 is not available 2020/11/04 06:03:34 USB emulation: enabled 2020/11/04 06:03:34 hci packet injection: enabled 2020/11/04 06:03:34 wifi device emulation: enabled 2020/11/04 06:03:39 suppressing KCSAN reports in functions: 'blk_mq_dispatch_rq_list' '__xa_clear_mark' '__dentry_kill' 'wbt_wait' 'alloc_pid' 'io_sq_thread' '__ext4_update_other_inode_time' 'audit_log_start' 'dd_has_work' 'snd_rawmidi_poll' 'ext4_mark_iloc_dirty' 'get_cpu_iowait_time_us' 'blk_mq_rq_ctx_init' 'ext4_mb_regular_allocator' 'n_tty_receive_buf_common' 'pcpu_alloc' 'shmem_add_to_page_cache' 'do_sys_poll' '__mark_inode_dirty' 'blk_mq_sched_dispatch_requests' 'ext4_free_inodes_count' 'tick_sched_timer' 'dec_zone_page_state' 'do_signal_stop' 'dput' 'do_select' 'ext4_setattr' 'do_coredump' 'block_page_mkwrite' 'generic_write_end' '__io_cqring_fill_event' 'shmem_mknod' 'write_cache_pages' 'futex_wait_queue_me' '__xa_set_mark' '__process_echoes' 'ext4_mb_good_group' 'ptrace_check_attach' '__add_to_page_cache_locked' 'ext4_ext_try_to_merge_right' 'find_get_pages_range_tag' 'ext4_free_inode' '__delayacct_blkio_end' '__delete_from_page_cache' 'expire_timers' 'wbt_issue' 'xas_clear_mark' '_prb_read_valid' 'do_nanosleep' 'n_tty_read' 'kauditd_thread' 'xas_find_marked' 'generic_file_buffered_read' 'exit_mm' 'do_readlinkat' 'tick_nohz_next_event' 'ext4_writepages' '__ext4_new_inode' 'ext4_set_iomap' 06:06:24 executing program 0: clone(0x1f000000, 0x0, 0x0, 0x0, 0x0) 06:06:24 executing program 1: r0 = openat$vnet(0xffffffffffffff9c, &(0x7f0000000000)='/dev/vhost-net\x00', 0x2, 0x0) ioctl$VHOST_SET_OWNER(r0, 0xc020660b, 0x0) 06:06:24 executing program 2: clock_gettime(0x0, &(0x7f0000003600)) 06:06:25 executing program 3: r0 = openat$vnet(0xffffffffffffff9c, &(0x7f0000000000)='/dev/vhost-net\x00', 0x2, 0x0) ioctl$VHOST_SET_OWNER(r0, 0x2, 0x0) 06:06:25 executing program 4: clone(0x900, 0x0, 0x0, 0x0, 0x0) socketpair$unix(0x1, 0x5, 0x0, &(0x7f0000001500)={0xffffffffffffffff, 0xffffffffffffffff}) ioctl$ifreq_SIOCGIFINDEX_wireguard(r0, 0x8933, &(0x7f0000001a00)={'wg2\x00'}) 06:06:25 executing program 5: r0 = socket$inet6_tcp(0xa, 0x1, 0x0) sendto$inet6(r0, 0x0, 0x0, 0x20000814, &(0x7f00000002c0)={0xa, 0x0, 0x0, @remote, 0x4}, 0x71) sendto$inet6(r0, 0x0, 0x0, 0x0, 0x0, 0x0) syzkaller login: [ 201.594366][ T8436] ================================================================== [ 201.636091][ T8436] BUG: KCSAN: data-race in do_epoll_ctl / do_epoll_wait [ 201.643018][ T8436] [ 201.645340][ T8436] write to 0xffff88810ca06a18 of 8 bytes by task 8438 on cpu 1: [ 201.652962][ T8436] do_epoll_ctl+0x1ab2/0x1c10 [ 201.657627][ T8436] __x64_sys_epoll_ctl+0xb3/0xe0 [ 201.662553][ T8436] do_syscall_64+0x39/0x80 [ 201.666958][ T8436] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 201.672830][ T8436] [ 201.675142][ T8436] read to 0xffff88810ca06a18 of 8 bytes by task 8436 on cpu 0: [ 201.682672][ T8436] do_epoll_wait+0x38e/0x810 [ 201.687250][ T8436] __x64_sys_epoll_pwait+0x92/0x150 [ 201.692429][ T8436] do_syscall_64+0x39/0x80 [ 201.696814][ T8436] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 201.702672][ T8436] [ 201.704971][ T8436] Reported by Kernel Concurrency Sanitizer on: [ 201.711096][ T8436] CPU: 0 PID: 8436 Comm: syz-fuzzer Not tainted 5.10.0-rc2-syzkaller #0 [ 201.719426][ T8436] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 201.729452][ T8436] ================================================================== [ 201.737482][ T8436] Kernel panic - not syncing: panic_on_warn set ... [ 201.744074][ T8436] CPU: 0 PID: 8436 Comm: syz-fuzzer Not tainted 5.10.0-rc2-syzkaller #0 [ 201.752486][ T8436] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 201.762508][ T8436] Call Trace: [ 201.765785][ T8436] dump_stack+0x116/0x15d [ 201.770266][ T8436] panic+0x1e7/0x5fa [ 201.774154][ T8436] ? vprintk_emit+0x2f2/0x370 [ 201.778815][ T8436] kcsan_report+0x67b/0x680 [ 201.783290][ T8436] ? irqentry_exit_cond_resched+0x22/0x40 [ 201.788979][ T8436] ? kcsan_setup_watchpoint+0x46a/0x4d0 [ 201.794494][ T8436] ? do_epoll_wait+0x38e/0x810 [ 201.799226][ T8436] ? __x64_sys_epoll_pwait+0x92/0x150 [ 201.804565][ T8436] ? do_syscall_64+0x39/0x80 [ 201.809126][ T8436] ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 201.815166][ T8436] ? pipe_write+0xbc0/0xbc0 [ 201.819641][ T8436] ? ep_send_events_proc+0x4e3/0x5f0 [ 201.824896][ T8436] kcsan_setup_watchpoint+0x46a/0x4d0 [ 201.830239][ T8436] do_epoll_wait+0x38e/0x810 [ 201.834799][ T8436] ? init_wait_entry+0x30/0x30 [ 201.839532][ T8436] ? __fpregs_load_activate+0x8f/0x1f0 [ 201.844959][ T8436] __x64_sys_epoll_pwait+0x92/0x150 [ 201.850125][ T8436] do_syscall_64+0x39/0x80 [ 201.854511][ T8436] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 201.860390][ T8436] RIP: 0033:0x469240 [ 201.864272][ T8436] 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 [ 201.883846][ T8436] RSP: 002b:000000c0000497f0 EFLAGS: 00000246 ORIG_RAX: 0000000000000119 [ 201.892224][ T8436] RAX: ffffffffffffffda RBX: 0000000000000bb5 RCX: 0000000000469240 [ 201.900166][ T8436] RDX: 0000000000000080 RSI: 000000c000049840 RDI: 0000000000000003 [ 201.908107][ T8436] RBP: 000000c000049e40 R08: 0000000000000000 R09: 0000000000000000 [ 201.916050][ T8436] R10: 0000000000000bb5 R11: 0000000000000246 R12: 0000000000000003 [ 201.924015][ T8436] R13: 000000c000000f00 R14: 000080c02eafa000 R15: 000080c02eb19fff [ 201.932498][ T8436] Kernel Offset: disabled [ 201.936800][ T8436] Rebooting in 86400 seconds..