[ 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 '10.128.1.32' (ECDSA) to the list of known hosts. 2020/10/28 18:36:41 fuzzer started 2020/10/28 18:36:41 dialing manager at 10.128.0.105:46815 2020/10/28 18:36:45 syscalls: 3452 2020/10/28 18:36:45 code coverage: enabled 2020/10/28 18:36:45 comparison tracing: enabled 2020/10/28 18:36:45 extra coverage: enabled 2020/10/28 18:36:45 setuid sandbox: enabled 2020/10/28 18:36:45 namespace sandbox: enabled 2020/10/28 18:36:45 Android sandbox: /sys/fs/selinux/policy does not exist 2020/10/28 18:36:45 fault injection: enabled 2020/10/28 18:36:45 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2020/10/28 18:36:45 net packet injection: enabled 2020/10/28 18:36:45 net device setup: enabled 2020/10/28 18:36:45 concurrency sanitizer: enabled 2020/10/28 18:36:45 devlink PCI setup: PCI device 0000:00:10.0 is not available 2020/10/28 18:36:45 USB emulation: enabled 2020/10/28 18:36:45 hci packet injection: enabled 2020/10/28 18:36:45 wifi device emulation: enabled 2020/10/28 18:36:48 suppressing KCSAN reports in functions: 'alloc_pid' 'virtnet_poll' 'blk_mq_dispatch_rq_list' '__add_to_page_cache_locked' '__send_signal' 'wbt_issue' 'kauditd_thread' 'snd_rawmidi_kernel_write1' 'shmem_unlink' 'unix_dgram_connect' 'ext4_ext_try_to_merge_right' 'do_select' 'generic_write_end' 'futex_wait_queue_me' 'ext4_writepages' '__io_cqring_fill_event' 'blk_mq_rq_ctx_init' '__ext4_new_inode' '__xa_clear_mark' 'do_nanosleep' 'find_get_pages_range_tag' 'blk_mq_sched_dispatch_requests' 'do_sys_poll' 'ext4_mb_good_group' 'do_signal_stop' 'ext4_free_inode' 'ext4_free_inodes_count' 'dd_has_work' 'shmem_add_to_page_cache' '__mod_timer' 'do_epoll_ctl' syzkaller login: [ 41.191449][ T8428] ================================================================== [ 41.199793][ T8428] BUG: KCSAN: data-race in __delayacct_blkio_end / __delayacct_blkio_start [ 41.208353][ T8428] [ 41.210669][ T8428] write to 0xffff8881015b7cd8 of 8 bytes by task 8426 on cpu 0: [ 41.218287][ T8428] __delayacct_blkio_start+0x35/0x40 [ 41.223544][ T8428] __schedule+0x18c/0x550 [ 41.227843][ T8428] schedule+0x7f/0xb0 [ 41.231806][ T8428] io_schedule+0x3b/0x50 [ 41.236074][ T8428] wait_on_page_bit_common+0x633/0x910 [ 41.241630][ T8428] filemap_fault+0x87a/0x12e0 [ 41.246326][ T8428] ext4_filemap_fault+0x4b/0x60 [ 41.251151][ T8428] do_read_fault+0x403/0x760 [ 41.255741][ T8428] handle_mm_fault+0xfeb/0x1770 [ 41.260568][ T8428] do_user_addr_fault+0x33e/0x730 [ 41.265565][ T8428] exc_page_fault+0x91/0x290 [ 41.270134][ T8428] asm_exc_page_fault+0x1e/0x30 [ 41.274950][ T8428] [ 41.277254][ T8428] read to 0xffff8881015b7cd8 of 8 bytes by task 8428 on cpu 1: [ 41.284779][ T8428] __delayacct_blkio_end+0x70/0xf0 [ 41.289873][ T8428] try_to_wake_up+0x107/0x470 [ 41.294568][ T8428] wake_page_function+0xd9/0x200 [ 41.299503][ T8428] __wake_up_common+0xbc/0x130 [ 41.304241][ T8428] wake_up_page_bit+0xa4/0x190 [ 41.308975][ T8428] filemap_map_pages+0x5ad/0x9a0 [ 41.313896][ T8428] do_read_fault+0x233/0x760 [ 41.318478][ T8428] handle_mm_fault+0xfeb/0x1770 [ 41.323301][ T8428] do_user_addr_fault+0x33e/0x730 [ 41.328296][ T8428] exc_page_fault+0x91/0x290 [ 41.332855][ T8428] asm_exc_page_fault+0x1e/0x30 [ 41.337689][ T8428] [ 41.339988][ T8428] Reported by Kernel Concurrency Sanitizer on: [ 41.346112][ T8428] CPU: 1 PID: 8428 Comm: syz-fuzzer Not tainted 5.10.0-rc1-syzkaller #0 [ 41.354416][ T8428] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 41.364442][ T8428] ================================================================== [ 41.372558][ T8428] Kernel panic - not syncing: panic_on_warn set ... [ 41.379117][ T8428] CPU: 1 PID: 8428 Comm: syz-fuzzer Not tainted 5.10.0-rc1-syzkaller #0 [ 41.387405][ T8428] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 41.397488][ T8428] Call Trace: [ 41.400763][ T8428] dump_stack+0x116/0x15d [ 41.405081][ T8428] panic+0x1e7/0x5fa [ 41.408953][ T8428] ? vprintk_emit+0x2f2/0x370 [ 41.413618][ T8428] kcsan_report+0x67b/0x680 [ 41.418095][ T8428] ? kcsan_setup_watchpoint+0x46a/0x4d0 [ 41.423615][ T8428] ? __delayacct_blkio_end+0x70/0xf0 [ 41.428877][ T8428] ? try_to_wake_up+0x107/0x470 [ 41.433700][ T8428] ? wake_page_function+0xd9/0x200 [ 41.438779][ T8428] ? __wake_up_common+0xbc/0x130 [ 41.443687][ T8428] ? wake_up_page_bit+0xa4/0x190 [ 41.448594][ T8428] ? filemap_map_pages+0x5ad/0x9a0 [ 41.453679][ T8428] ? do_read_fault+0x233/0x760 [ 41.458411][ T8428] ? handle_mm_fault+0xfeb/0x1770 [ 41.463406][ T8428] ? do_user_addr_fault+0x33e/0x730 [ 41.468575][ T8428] ? exc_page_fault+0x91/0x290 [ 41.473335][ T8428] ? asm_exc_page_fault+0x1e/0x30 [ 41.478350][ T8428] ? __rcu_read_unlock+0x51/0x220 [ 41.483361][ T8428] ? __rcu_read_unlock+0x51/0x220 [ 41.488375][ T8428] kcsan_setup_watchpoint+0x46a/0x4d0 [ 41.493719][ T8428] __delayacct_blkio_end+0x70/0xf0 [ 41.498827][ T8428] try_to_wake_up+0x107/0x470 [ 41.503479][ T8428] wake_page_function+0xd9/0x200 [ 41.508403][ T8428] __wake_up_common+0xbc/0x130 [ 41.513154][ T8428] wake_up_page_bit+0xa4/0x190 [ 41.517975][ T8428] filemap_map_pages+0x5ad/0x9a0 [ 41.522883][ T8428] do_read_fault+0x233/0x760 [ 41.527443][ T8428] handle_mm_fault+0xfeb/0x1770 [ 41.532268][ T8428] do_user_addr_fault+0x33e/0x730 [ 41.537265][ T8428] exc_page_fault+0x91/0x290 [ 41.541826][ T8428] ? asm_exc_page_fault+0x8/0x30 [ 41.546736][ T8428] asm_exc_page_fault+0x1e/0x30 [ 41.551569][ T8428] RIP: 0033:0x41f64a [ 41.555436][ T8428] 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 [ 41.575025][ T8428] RSP: 002b:000000c00004be18 EFLAGS: 00010283 [ 41.581154][ T8428] RAX: 00007f2a7c0cf000 RBX: 0000000000000055 RCX: 0000000000040000 [ 41.589099][ T8428] RDX: 00000000019cb100 RSI: 0000000000015f08 RDI: 0000000000000001 [ 41.597046][ T8428] RBP: 000000c00004be68 R08: 00000000019e1008 R09: 0000000000000036 [ 41.604990][ T8428] R10: 0000000000010000 R11: 0000000000000008 R12: 00000000011f22a0 [ 41.612933][ T8428] R13: 0000000000eca780 R14: 0000000000000002 R15: 0000000000000001 [ 42.686240][ T8428] Shutting down cpus with NMI [ 42.691545][ T8428] Kernel Offset: disabled [ 42.695852][ T8428] Rebooting in 86400 seconds..