[ 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 '10.128.1.54' (ECDSA) to the list of known hosts. 2020/08/01 20:56:34 fuzzer started 2020/08/01 20:56:34 dialing manager at 10.128.0.105:32803 2020/08/01 20:56:34 syscalls: 3254 2020/08/01 20:56:34 code coverage: enabled 2020/08/01 20:56:34 comparison tracing: enabled 2020/08/01 20:56:34 extra coverage: enabled 2020/08/01 20:56:34 setuid sandbox: enabled 2020/08/01 20:56:34 namespace sandbox: enabled 2020/08/01 20:56:34 Android sandbox: /sys/fs/selinux/policy does not exist 2020/08/01 20:56:34 fault injection: enabled 2020/08/01 20:56:34 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2020/08/01 20:56:34 net packet injection: enabled 2020/08/01 20:56:34 net device setup: enabled 2020/08/01 20:56:34 concurrency sanitizer: enabled 2020/08/01 20:56:34 devlink PCI setup: PCI device 0000:00:10.0 is not available 2020/08/01 20:56:34 USB emulation: enabled 2020/08/01 20:56:34 hci packet injection: enabled 2020/08/01 20:56:38 suppressing KCSAN reports in functions: 'ext4_free_inode' 'blk_mq_sched_dispatch_requests' 'do_signal_stop' 'blk_mq_dispatch_rq_list' 'ext4_mb_good_group' 'expire_timers' 'futex_wait_queue_me' 'wbt_issue' 'xas_clear_mark' 'get_cpu_idle_time_us' 'pcpu_alloc' 'ext4_free_inodes_count' 'ext4_mark_iloc_dirty' 'n_tty_receive_buf_common' 'do_select' 'kauditd_thread' '__xa_clear_mark' 'find_get_pages_range_tag' '__send_signal' 'blk_mq_rq_ctx_init' '__delete_from_page_cache' 'do_readlinkat' '__mark_inode_dirty' 'ptrace_check_attach' 'alloc_pid' '__ext4_new_inode' 'dd_has_work' 'exit_mm' 'ondemand_readahead' 'bpf_lru_pop_free' 'generic_write_end' '__delayacct_blkio_end' 'shmem_getpage_gfp' 'wg_packet_decrypt_worker' 'page_counter_charge' 'do_syslog' 'shmem_unlink' 'snd_rawmidi_poll' 'do_epoll_wait' '__add_to_page_cache_locked' 'generic_file_buffered_read' '__filemap_fdatawrite_range' 'snd_rawmidi_transmit' 'do_sys_poll' 'complete_signal' 'ext4_sync_file' 'do_nanosleep' 'ext4_da_write_end' 'shmem_file_read_iter' syzkaller login: [ 109.308190][ T8664] ================================================================== [ 109.316299][ T8664] BUG: KCSAN: data-race in __mod_timer / timer_clear_idle [ 109.323369][ T8664] [ 109.325669][ T8664] write to 0xffff88812c01cb24 of 1 bytes by task 0 on cpu 0: [ 109.333004][ T8664] timer_clear_idle+0x2e/0x40 [ 109.337649][ T8664] tick_nohz_idle_retain_tick+0x3e/0x40 [ 109.343172][ T8664] do_idle+0x287/0x310 [ 109.347219][ T8664] cpu_startup_entry+0x15/0x20 [ 109.351966][ T8664] rest_init+0xd8/0xe0 [ 109.356003][ T8664] arch_call_rest_init+0xa/0xb [ 109.360730][ T8664] start_kernel+0x608/0x6d0 [ 109.365199][ T8664] secondary_startup_64+0xa4/0xb0 [ 109.370184][ T8664] [ 109.372482][ T8664] read to 0xffff88812c01cb24 of 1 bytes by task 8664 on cpu 1: [ 109.379992][ T8664] __mod_timer+0xbd7/0x1020 [ 109.384476][ T8664] mod_timer+0x1b/0x20 [ 109.388512][ T8664] sk_reset_timer+0x1f/0xa0 [ 109.392999][ T8664] tcp_send_delayed_ack+0x191/0x250 [ 109.398174][ T8664] __tcp_ack_snd_check+0x313/0x530 [ 109.403251][ T8664] tcp_rcv_established+0x12e2/0x1520 [ 109.408515][ T8664] tcp_v4_do_rcv+0x25e/0x480 [ 109.413070][ T8664] __release_sock+0xf5/0x260 [ 109.417634][ T8664] release_sock+0x40/0x110 [ 109.422020][ T8664] tcp_recvmsg+0x16ba/0x1c10 [ 109.426579][ T8664] inet_recvmsg+0xa9/0x210 [ 109.430962][ T8664] sock_read_iter+0x19c/0x1e0 [ 109.435606][ T8664] vfs_read+0x523/0x590 [ 109.439742][ T8664] ksys_read+0xce/0x180 [ 109.443877][ T8664] __x64_sys_read+0x3e/0x50 [ 109.448348][ T8664] do_syscall_64+0x51/0xb0 [ 109.452755][ T8664] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 109.458607][ T8664] [ 109.460936][ T8664] Reported by Kernel Concurrency Sanitizer on: [ 109.467058][ T8664] CPU: 1 PID: 8664 Comm: syz-fuzzer Not tainted 5.8.0-rc7-syzkaller #0 [ 109.475254][ T8664] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 109.485284][ T8664] ================================================================== [ 109.493322][ T8664] Kernel panic - not syncing: panic_on_warn set ... [ 109.499875][ T8664] CPU: 1 PID: 8664 Comm: syz-fuzzer Not tainted 5.8.0-rc7-syzkaller #0 [ 109.508072][ T8664] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 109.518103][ T8664] Call Trace: [ 109.521366][ T8664] dump_stack+0x10f/0x19d [ 109.525664][ T8664] panic+0x207/0x64a [ 109.529530][ T8664] ? vprintk_emit+0x44a/0x4f0 [ 109.534175][ T8664] kcsan_report+0x684/0x690 [ 109.538648][ T8664] ? kcsan_setup_watchpoint+0x453/0x4d0 [ 109.544161][ T8664] ? __mod_timer+0xbd7/0x1020 [ 109.548804][ T8664] ? mod_timer+0x1b/0x20 [ 109.553014][ T8664] ? sk_reset_timer+0x1f/0xa0 [ 109.557661][ T8664] ? tcp_send_delayed_ack+0x191/0x250 [ 109.562995][ T8664] ? __tcp_ack_snd_check+0x313/0x530 [ 109.568244][ T8664] ? tcp_rcv_established+0x12e2/0x1520 [ 109.573668][ T8664] ? tcp_v4_do_rcv+0x25e/0x480 [ 109.578396][ T8664] ? __release_sock+0xf5/0x260 [ 109.583221][ T8664] ? release_sock+0x40/0x110 [ 109.587792][ T8664] ? tcp_recvmsg+0x16ba/0x1c10 [ 109.592534][ T8664] ? inet_recvmsg+0xa9/0x210 [ 109.597088][ T8664] ? sock_read_iter+0x19c/0x1e0 [ 109.601918][ T8664] ? vfs_read+0x523/0x590 [ 109.606233][ T8664] ? ksys_read+0xce/0x180 [ 109.610532][ T8664] ? __x64_sys_read+0x3e/0x50 [ 109.615184][ T8664] ? do_syscall_64+0x51/0xb0 [ 109.619743][ T8664] ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 109.625780][ T8664] ? __tcp_select_window+0x340/0x510 [ 109.631034][ T8664] kcsan_setup_watchpoint+0x453/0x4d0 [ 109.636376][ T8664] __mod_timer+0xbd7/0x1020 [ 109.640859][ T8664] mod_timer+0x1b/0x20 [ 109.644895][ T8664] sk_reset_timer+0x1f/0xa0 [ 109.649366][ T8664] tcp_send_delayed_ack+0x191/0x250 [ 109.654533][ T8664] __tcp_ack_snd_check+0x313/0x530 [ 109.659612][ T8664] tcp_rcv_established+0x12e2/0x1520 [ 109.664864][ T8664] tcp_v4_do_rcv+0x25e/0x480 [ 109.669435][ T8664] __release_sock+0xf5/0x260 [ 109.673996][ T8664] release_sock+0x40/0x110 [ 109.678382][ T8664] tcp_recvmsg+0x16ba/0x1c10 [ 109.682954][ T8664] ? aa_sk_perm+0x499/0x540 [ 109.687428][ T8664] inet_recvmsg+0xa9/0x210 [ 109.691811][ T8664] ? apparmor_socket_recvmsg+0x25/0x30 [ 109.697235][ T8664] sock_read_iter+0x19c/0x1e0 [ 109.702228][ T8664] vfs_read+0x523/0x590 [ 109.706351][ T8664] ksys_read+0xce/0x180 [ 109.710473][ T8664] __x64_sys_read+0x3e/0x50 [ 109.714942][ T8664] do_syscall_64+0x51/0xb0 [ 109.719326][ T8664] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 109.725197][ T8664] RIP: 0033:0x4b3cdb [ 109.729061][ T8664] Code: ff e9 69 ff ff ff cc cc cc cc cc cc cc cc cc e8 bb a1 f8 ff 48 8b 7c 24 10 48 8b 74 24 18 48 8b 54 24 20 48 8b 44 24 08 0f 05 <48> 3d 01 f0 ff ff 76 20 48 c7 44 24 28 ff ff ff ff 48 c7 44 24 30 [ 109.748642][ T8664] RSP: 002b:000000c0000ef8b8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 109.757026][ T8664] RAX: ffffffffffffffda RBX: 000000c00002e800 RCX: 00000000004b3cdb [ 109.764964][ T8664] RDX: 0000000000001000 RSI: 000000c0002fc000 RDI: 0000000000000006 [ 109.772928][ T8664] RBP: 000000c0000ef908 R08: 0000000000000001 R09: 0000000000000002 [ 109.780867][ T8664] R10: 0000000000002f9e R11: 0000000000000212 R12: ffffffffffffffff [ 109.788805][ T8664] R13: 0000000000002000 R14: 0000000000000002 R15: 0000000000000002 [ 110.864024][ T8664] Shutting down cpus with NMI [ 110.869833][ T8664] Kernel Offset: disabled [ 110.874140][ T8664] Rebooting in 86400 seconds..