Starting mcstransd: [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [ 37.949972] audit: type=1800 audit(1571350116.700:33): pid=7307 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:kernel_t:s0 op=collect_data cause=failed(directio) comm="startpar" name="rc.local" dev="sda1" ino=2465 res=0 Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 41.915122] kauditd_printk_skb: 1 callbacks suppressed [ 41.915136] audit: type=1400 audit(1571350120.660:35): avc: denied { map } for pid=7484 comm="bash" path="/bin/bash" dev="sda1" ino=1457 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 Warning: Permanently added '10.128.15.208' (ECDSA) to the list of known hosts. executing program [ 52.723347] audit: type=1400 audit(1571350131.470:36): avc: denied { map } for pid=7496 comm="syz-executor086" path="/root/syz-executor086820530" dev="sda1" ino=16484 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 [ 52.799635] audit: type=1400 audit(1571350131.550:37): avc: denied { map } for pid=7497 comm="syz-executor086" path="/dev/usbmon4" dev="devtmpfs" ino=16585 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:usbmon_device_t:s0 tclass=chr_file permissive=1 [ 52.818654] [ 52.826863] ====================================================== [ 52.833160] WARNING: possible circular locking dependency detected [ 52.839456] 4.19.80 #0 Not tainted [ 52.842971] ------------------------------------------------------ [ 52.849262] syz-executor086/7499 is trying to acquire lock: [ 52.854949] 00000000dcef28b1 (&rp->fetch_lock){+.+.}, at: mon_bin_vma_fault+0x73/0x2d0 [ 52.863000] [ 52.863000] but task is already holding lock: [ 52.868948] 00000000fc161845 (&mm->mmap_sem){++++}, at: __mm_populate+0x270/0x380 [ 52.876557] [ 52.876557] which lock already depends on the new lock. [ 52.876557] [ 52.884849] [ 52.884849] the existing dependency chain (in reverse order) is: [ 52.892445] [ 52.892445] -> #1 (&mm->mmap_sem){++++}: [ 52.897971] __might_fault+0x15e/0x1e0 [ 52.902359] _copy_to_user+0x30/0x120 [ 52.906662] mon_bin_read+0x329/0x640 [ 52.910975] __vfs_read+0x114/0x800 [ 52.915103] vfs_read+0x194/0x3d0 [ 52.919067] ksys_read+0x14f/0x2d0 [ 52.923104] __x64_sys_read+0x73/0xb0 [ 52.927404] do_syscall_64+0xfd/0x620 [ 52.931706] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 52.937392] [ 52.937392] -> #0 (&rp->fetch_lock){+.+.}: [ 52.943094] lock_acquire+0x16f/0x3f0 [ 52.947394] __mutex_lock+0xf7/0x1300 [ 52.951693] mutex_lock_nested+0x16/0x20 [ 52.956256] mon_bin_vma_fault+0x73/0x2d0 [ 52.960906] __do_fault+0x111/0x480 [ 52.965029] __handle_mm_fault+0x2d78/0x3f80 [ 52.969936] handle_mm_fault+0x1b5/0x690 [ 52.974496] __get_user_pages+0x609/0x17a0 [ 52.979328] populate_vma_page_range+0x20d/0x2a0 [ 52.984591] __mm_populate+0x204/0x380 [ 52.988988] vm_mmap_pgoff+0x213/0x230 [ 52.993374] ksys_mmap_pgoff+0x4aa/0x630 [ 52.997935] __x64_sys_mmap+0xe9/0x1b0 [ 53.002321] do_syscall_64+0xfd/0x620 [ 53.006634] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 53.012325] [ 53.012325] other info that might help us debug this: [ 53.012325] [ 53.020454] Possible unsafe locking scenario: [ 53.020454] [ 53.026498] CPU0 CPU1 [ 53.031155] ---- ---- [ 53.035806] lock(&mm->mmap_sem); [ 53.039335] lock(&rp->fetch_lock); [ 53.045541] lock(&mm->mmap_sem); [ 53.051573] lock(&rp->fetch_lock); [ 53.055264] [ 53.055264] *** DEADLOCK *** [ 53.055264] [ 53.061303] 1 lock held by syz-executor086/7499: [ 53.066031] #0: 00000000fc161845 (&mm->mmap_sem){++++}, at: __mm_populate+0x270/0x380 [ 53.074080] [ 53.074080] stack backtrace: [ 53.078569] CPU: 1 PID: 7499 Comm: syz-executor086 Not tainted 4.19.80 #0 [ 53.085471] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 53.094800] Call Trace: [ 53.097373] dump_stack+0x172/0x1f0 [ 53.100982] print_circular_bug.isra.0.cold+0x1cc/0x28f [ 53.106326] __lock_acquire+0x2e19/0x49c0 [ 53.110451] ? _raw_spin_unlock_irqrestore+0x6b/0xe0 [ 53.115534] ? depot_save_stack+0x1de/0x44f [ 53.119834] ? _raw_spin_unlock_irqrestore+0x6b/0xe0 [ 53.124915] ? lockdep_hardirqs_on+0x415/0x5d0 [ 53.129483] ? mark_held_locks+0x100/0x100 [ 53.133700] ? save_stack+0x45/0xd0 [ 53.137304] ? kasan_kmalloc+0xce/0xf0 [ 53.141171] ? kasan_slab_alloc+0xf/0x20 [ 53.145211] ? kmem_cache_alloc+0x12e/0x700 [ 53.149511] ? __lock_is_held+0xb6/0x140 [ 53.153552] ? __mm_populate+0x204/0x380 [ 53.157596] ? mon_bin_vma_fault+0x73/0x2d0 [ 53.161912] lock_acquire+0x16f/0x3f0 [ 53.165700] ? mon_bin_vma_fault+0x73/0x2d0 [ 53.170007] ? mon_bin_vma_fault+0x73/0x2d0 [ 53.174308] __mutex_lock+0xf7/0x1300 [ 53.178099] ? mon_bin_vma_fault+0x73/0x2d0 [ 53.182415] ? __lock_is_held+0xb6/0x140 [ 53.186453] ? mon_bin_vma_fault+0x73/0x2d0 [ 53.190757] ? mutex_trylock+0x1e0/0x1e0 [ 53.194809] ? __lock_is_held+0xb6/0x140 [ 53.198853] ? rcu_read_lock_sched_held+0x110/0x130 [ 53.203863] ? kmem_cache_alloc+0x32a/0x700 [ 53.208177] mutex_lock_nested+0x16/0x20 [ 53.212229] ? mutex_lock_nested+0x16/0x20 [ 53.216447] mon_bin_vma_fault+0x73/0x2d0 [ 53.220587] __do_fault+0x111/0x480 [ 53.224282] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 53.229821] __handle_mm_fault+0x2d78/0x3f80 [ 53.234216] ? vmf_insert_mixed_mkwrite+0x90/0x90 [ 53.239088] ? count_memcg_event_mm+0x2b1/0x4d0 [ 53.243834] handle_mm_fault+0x1b5/0x690 [ 53.247898] __get_user_pages+0x609/0x17a0 [ 53.252123] ? follow_page_mask+0x19d0/0x19d0 [ 53.256629] ? memset+0x32/0x40 [ 53.259903] populate_vma_page_range+0x20d/0x2a0 [ 53.264648] __mm_populate+0x204/0x380 [ 53.268516] ? populate_vma_page_range+0x2a0/0x2a0 [ 53.273428] vm_mmap_pgoff+0x213/0x230 [ 53.277296] ? vma_is_stack_for_current+0xd0/0xd0 [ 53.282119] ? iterate_fd+0x360/0x360 [ 53.285900] ksys_mmap_pgoff+0x4aa/0x630 [ 53.289941] ? find_mergeable_anon_vma+0x2e0/0x2e0 [ 53.294858] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 53.299594] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 53.304327] ? do_syscall_64+0x26/0x620 [ 53.308279] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 53.313622] __x64_sys_mmap+0xe9/0x1b0 [ 53.317498] do_syscall_64+0xfd/0x620 [ 53.321280] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 53.326447] RIP: 0033:0x44a689 [ 53.329619] Code: e8 8c b5 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 2b cc fb ff c3 66 2e 0f 1f 84 00 00 00 00 [ 53.348498] RSP: 002b:00007f5860a74cd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 [ 53.356187] RAX: ffffffffffffffda RBX: 00000000006dbc38 RCX: 000000000044a689 [ 53.363437] RDX: 0000000002000001 RSI: 0000000002000000 RDI: 0000000020ffd000 [ 53.370685] RBP: 00000000006dbc30 R08: 0000000000000005 R09: 0000000000000000 [ 53.377943] R10: 03eb6b06d1207692 R11: 0000000000000246 R12: 00000000006dbc3c [ 53.385190] R13: 00007fff88eb4f2f R14: 00007f5860a759c0 R15: 20c49ba5e353f7cf executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program