[ 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 '10.128.0.211' (ECDSA) to the list of known hosts. 2020/11/16 10:14:26 fuzzer started 2020/11/16 10:14:26 dialing manager at 10.128.0.105:38281 2020/11/16 10:14:32 syscalls: 3448 2020/11/16 10:14:32 code coverage: enabled 2020/11/16 10:14:32 comparison tracing: enabled 2020/11/16 10:14:32 extra coverage: enabled 2020/11/16 10:14:32 setuid sandbox: enabled 2020/11/16 10:14:32 namespace sandbox: enabled 2020/11/16 10:14:32 Android sandbox: /sys/fs/selinux/policy does not exist 2020/11/16 10:14:32 fault injection: enabled 2020/11/16 10:14:32 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2020/11/16 10:14:32 net packet injection: enabled 2020/11/16 10:14:32 net device setup: enabled 2020/11/16 10:14:32 concurrency sanitizer: enabled 2020/11/16 10:14:32 devlink PCI setup: PCI device 0000:00:10.0 is not available 2020/11/16 10:14:32 USB emulation: enabled 2020/11/16 10:14:32 hci packet injection: enabled 2020/11/16 10:14:32 wifi device emulation: enabled 2020/11/16 10:14:36 suppressing KCSAN reports in functions: 'expire_timers' '__io_cqring_fill_event' 'vfs_readlink' 'blk_mq_rq_ctx_init' 'blk_mq_dispatch_rq_list' 'wbt_issue' 'do_readlinkat' 'generic_write_end' 'ext4_free_inodes_count' 'ext4_mb_good_group' 'pcpu_alloc' 'audit_log_start' 'ext4_mark_iloc_dirty' '__xa_clear_mark' 'do_signal_stop' 'shmem_mknod' 'ext4_writepages' '__ext4_new_inode' 'do_sys_poll' 'blk_mq_sched_dispatch_requests' 'ext4_mb_regular_allocator' 'find_get_pages_range_tag' 'ext4_free_inode' 'exit_mm' 'kauditd_thread' '_prb_read_valid' 'ext4_ext_try_to_merge_right' 'alloc_pid' 'do_nanosleep' 'do_select' '__add_to_page_cache_locked' 'n_tty_receive_buf_common' 'dd_has_work' 'snd_rawmidi_poll' 'ext4_ext_handle_unwritten_extents' 'xas_find_marked' 'ext4_handle_inode_extension' syzkaller login: [ 41.277017][ T8454] ================================================================== [ 41.285331][ T8454] BUG: KCSAN: data-race in __delayacct_blkio_end / __delayacct_blkio_start [ 41.293905][ T8454] [ 41.296214][ T8454] write to 0xffff88810101ecd8 of 8 bytes by task 8445 on cpu 1: [ 41.303832][ T8454] __delayacct_blkio_start+0x35/0x40 [ 41.309105][ T8454] __schedule+0x18c/0x550 [ 41.314187][ T8454] schedule+0x7f/0xb0 [ 41.318141][ T8454] io_schedule+0x3b/0x50 [ 41.322357][ T8454] wait_on_page_bit_common+0x633/0x910 [ 41.327786][ T8454] filemap_fault+0x87a/0x12e0 [ 41.332433][ T8454] ext4_filemap_fault+0x4b/0x60 [ 41.337272][ T8454] do_read_fault+0x403/0x760 [ 41.341831][ T8454] handle_mm_fault+0xfeb/0x1770 [ 41.346656][ T8454] do_user_addr_fault+0x33e/0x730 [ 41.351677][ T8454] exc_page_fault+0x91/0x290 [ 41.356251][ T8454] asm_exc_page_fault+0x1e/0x30 [ 41.361087][ T8454] [ 41.363390][ T8454] read to 0xffff88810101ecd8 of 8 bytes by task 8454 on cpu 0: [ 41.370904][ T8454] __delayacct_blkio_end+0x70/0xf0 [ 41.376508][ T8454] try_to_wake_up+0x107/0x470 [ 41.381156][ T8454] wake_page_function+0xd9/0x200 [ 41.386167][ T8454] __wake_up_common+0xbc/0x130 [ 41.390900][ T8454] wake_up_page_bit+0xa4/0x190 [ 41.395634][ T8454] filemap_map_pages+0x81b/0x9a0 [ 41.400540][ T8454] do_read_fault+0x233/0x760 [ 41.405097][ T8454] handle_mm_fault+0xfeb/0x1770 [ 41.410025][ T8454] do_user_addr_fault+0x33e/0x730 [ 41.415017][ T8454] exc_page_fault+0x91/0x290 [ 41.419591][ T8454] asm_exc_page_fault+0x1e/0x30 [ 41.424408][ T8454] [ 41.426705][ T8454] Reported by Kernel Concurrency Sanitizer on: [ 41.432844][ T8454] CPU: 0 PID: 8454 Comm: syz-fuzzer Not tainted 5.10.0-rc4-syzkaller #0 [ 41.441153][ T8454] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 41.451451][ T8454] ================================================================== [ 41.459493][ T8454] Kernel panic - not syncing: panic_on_warn set ... [ 41.466065][ T8454] CPU: 0 PID: 8454 Comm: syz-fuzzer Not tainted 5.10.0-rc4-syzkaller #0 [ 41.474362][ T8454] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 41.484388][ T8454] Call Trace: [ 41.487671][ T8454] dump_stack+0x116/0x15d [ 41.491975][ T8454] panic+0x1e7/0x5fa [ 41.495854][ T8454] ? vprintk_emit+0x2f2/0x370 [ 41.500502][ T8454] kcsan_report+0x67b/0x680 [ 41.504990][ T8454] ? kcsan_setup_watchpoint+0x46a/0x4d0 [ 41.510520][ T8454] ? __delayacct_blkio_end+0x70/0xf0 [ 41.515776][ T8454] ? try_to_wake_up+0x107/0x470 [ 41.520597][ T8454] ? wake_page_function+0xd9/0x200 [ 41.525693][ T8454] ? __wake_up_common+0xbc/0x130 [ 41.530611][ T8454] ? wake_up_page_bit+0xa4/0x190 [ 41.535518][ T8454] ? filemap_map_pages+0x81b/0x9a0 [ 41.540597][ T8454] ? do_read_fault+0x233/0x760 [ 41.545454][ T8454] ? handle_mm_fault+0xfeb/0x1770 [ 41.550458][ T8454] ? do_user_addr_fault+0x33e/0x730 [ 41.555625][ T8454] ? exc_page_fault+0x91/0x290 [ 41.560361][ T8454] ? asm_exc_page_fault+0x1e/0x30 [ 41.565362][ T8454] ? rt_mutex_setprio+0x250/0x470 [ 41.570355][ T8454] ? __rcu_read_unlock+0x51/0x220 [ 41.575352][ T8454] kcsan_setup_watchpoint+0x46a/0x4d0 [ 41.580702][ T8454] __delayacct_blkio_end+0x70/0xf0 [ 41.585785][ T8454] try_to_wake_up+0x107/0x470 [ 41.590447][ T8454] wake_page_function+0xd9/0x200 [ 41.595372][ T8454] __wake_up_common+0xbc/0x130 [ 41.600164][ T8454] wake_up_page_bit+0xa4/0x190 [ 41.604901][ T8454] filemap_map_pages+0x81b/0x9a0 [ 41.609810][ T8454] do_read_fault+0x233/0x760 [ 41.614409][ T8454] handle_mm_fault+0xfeb/0x1770 [ 41.619243][ T8454] do_user_addr_fault+0x33e/0x730 [ 41.624248][ T8454] exc_page_fault+0x91/0x290 [ 41.628809][ T8454] ? asm_exc_page_fault+0x8/0x30 [ 41.633715][ T8454] asm_exc_page_fault+0x1e/0x30 [ 41.638543][ T8454] RIP: 0033:0x41f64a [ 41.642452][ T8454] Code: 31 ff eb 09 48 ff c7 d1 eb 48 83 c6 08 48 83 ff 08 0f 8d f3 00 00 00 48 39 ce 0f 83 ea 00 00 00 0f ba e3 00 73 de 4c 8d 04 16 <4d> 8b 00 4d 85 c0 74 d2 48 89 7c 24 40 4c 89 44 24 38 48 89 74 24 [ 41.662114][ T8454] RSP: 002b:000000c0002d7e18 EFLAGS: 00010287 [ 41.668151][ T8454] RAX: 00007fea3073d000 RBX: 0000000000000001 RCX: 0000000000040000 [ 41.676115][ T8454] RDX: 000000000188b0e0 RSI: 000000000000ef28 RDI: 0000000000000005 [ 41.684319][ T8454] RBP: 000000c0002d7e68 R08: 000000000189a008 R09: 0000000000000033 [ 41.692261][ T8454] R10: 0000000000010000 R11: 0000000000000060 R12: 00000000000000fe [ 41.700225][ T8454] R13: 000000c00002ff68 R14: 0000000000000008 R15: 0000000000000008 [ 42.772773][ T8454] Shutting down cpus with NMI [ 42.778566][ T8454] Kernel Offset: disabled [ 42.782898][ T8454] Rebooting in 86400 seconds..