[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Starting mcstransd: [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 9.973889] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 16.407626] random: crng init done Warning: Permanently added '10.128.0.111' (ECDSA) to the list of known hosts. 2018/09/23 08:02:51 parsed 1 programs 2018/09/23 08:02:53 executed programs: 0 [ 45.134448] audit: type=1400 audit(1537689779.048:5): avc: denied { associate } for pid=2075 comm="syz-executor1" name="syz1" scontext=unconfined_u:object_r:unlabeled_t:s0 tcontext=system_u:object_r:unlabeled_t:s0 tclass=filesystem permissive=1 2018/09/23 08:02:59 executed programs: 6 2018/09/23 08:03:04 executed programs: 452 2018/09/23 08:03:09 executed programs: 895 2018/09/23 08:03:14 executed programs: 1362 2018/09/23 08:03:19 executed programs: 1819 2018/09/23 08:03:24 executed programs: 2270 2018/09/23 08:03:29 executed programs: 2739 [ 79.292237] [ 79.293951] ====================================================== [ 79.300258] [ INFO: possible circular locking dependency detected ] [ 79.306657] 4.9.128+ #41 Not tainted [ 79.310392] ------------------------------------------------------- [ 79.316795] syz-executor2/14008 is trying to acquire lock: [ 79.322413] (&sig->cred_guard_mutex){+.+.+.}, at: [] lock_trace+0x44/0xc0 [ 79.331335] but task is already holding lock: [ 79.336025] (&p->lock){+.+.+.}, at: [] seq_read+0xdd/0x12d0 [ 79.343754] which lock already depends on the new lock. [ 79.343754] [ 79.350763] [ 79.350763] the existing dependency chain (in reverse order) is: [ 79.358381] -> #2 (&p->lock){+.+.+.}: [ 79.362892] lock_acquire+0x130/0x3e0 [ 79.367223] mutex_lock_nested+0xc0/0x870 [ 79.371894] seq_read+0xdd/0x12d0 [ 79.375861] proc_reg_read+0xfd/0x180 [ 79.380168] do_loop_readv_writev.part.1+0xd5/0x280 [ 79.385696] do_readv_writev+0x56e/0x7b0 [ 79.390274] vfs_readv+0x84/0xc0 [ 79.394136] default_file_splice_read+0x44b/0x7e0 [ 79.399472] do_splice_to+0x10c/0x170 [ 79.403767] SyS_splice+0x10d2/0x14d0 [ 79.408062] do_syscall_64+0x19f/0x480 [ 79.412455] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 79.418054] -> #1 (&pipe->mutex/1){+.+.+.}: [ 79.423112] lock_acquire+0x130/0x3e0 [ 79.427417] mutex_lock_nested+0xc0/0x870 [ 79.432087] fifo_open+0x15c/0x9e0 [ 79.436145] do_dentry_open+0x3ef/0xc90 [ 79.440623] vfs_open+0x11c/0x210 [ 79.444567] path_openat+0x542/0x2790 [ 79.448866] do_filp_open+0x197/0x270 [ 79.453159] do_open_execat+0x10f/0x640 [ 79.457631] do_execveat_common.isra.15+0x687/0x1f80 [ 79.463225] SyS_execve+0x42/0x50 [ 79.467172] do_syscall_64+0x19f/0x480 [ 79.471555] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 79.477151] -> #0 (&sig->cred_guard_mutex){+.+.+.}: [ 79.482790] __lock_acquire+0x3189/0x4a10 [ 79.487431] lock_acquire+0x130/0x3e0 [ 79.491726] mutex_lock_killable_nested+0xcc/0x960 [ 79.497151] lock_trace+0x44/0xc0 [ 79.501096] proc_pid_stack+0xdc/0x220 [ 79.505475] proc_single_show+0xfd/0x170 [ 79.510043] seq_read+0x4b6/0x12d0 [ 79.514076] do_loop_readv_writev.part.1+0xd5/0x280 [ 79.519600] do_readv_writev+0x56e/0x7b0 [ 79.524177] vfs_readv+0x84/0xc0 [ 79.528036] do_preadv+0x197/0x240 [ 79.532080] SyS_preadv+0x30/0x40 [ 79.536025] do_syscall_64+0x19f/0x480 [ 79.540420] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 79.546025] [ 79.546025] other info that might help us debug this: [ 79.546025] [ 79.554137] Chain exists of: &sig->cred_guard_mutex --> &pipe->mutex/1 --> &p->lock [ 79.563174] Possible unsafe locking scenario: [ 79.563174] [ 79.569204] CPU0 CPU1 [ 79.573841] ---- ---- [ 79.578478] lock(&p->lock); [ 79.581882] lock(&pipe->mutex/1); [ 79.588354] lock(&p->lock); [ 79.594199] lock(&sig->cred_guard_mutex); [ 79.598736] [ 79.598736] *** DEADLOCK *** [ 79.598736] [ 79.604767] 1 lock held by syz-executor2/14008: [ 79.609405] #0: (&p->lock){+.+.+.}, at: [] seq_read+0xdd/0x12d0 [ 79.617662] [ 79.617662] stack backtrace: [ 79.622131] CPU: 1 PID: 14008 Comm: syz-executor2 Not tainted 4.9.128+ #41 [ 79.629129] ffff8801c9d07568 ffffffff81af2469 ffffffff83aa8290 ffffffff83aa2c80 [ 79.637128] ffffffff83aa0fd0 ffff8801d318a090 ffff8801d31897c0 ffff8801c9d075b0 [ 79.645123] ffffffff813e79ed 0000000000000001 00000000d318a070 0000000000000001 [ 79.653116] Call Trace: [ 79.655696] [] dump_stack+0xc1/0x128 [ 79.661066] [] print_circular_bug.cold.36+0x2f7/0x432 [ 79.667886] [] __lock_acquire+0x3189/0x4a10 [ 79.673841] [] ? _raw_spin_unlock_irqrestore+0x45/0x70 [ 79.680754] [] ? trace_hardirqs_on+0x10/0x10 [ 79.686811] [] ? kasan_kmalloc.part.1+0x62/0xf0 [ 79.693102] [] ? kmem_cache_alloc_trace+0x117/0x2e0 [ 79.699743] [] ? proc_pid_stack+0xa2/0x220 [ 79.705603] [] ? proc_single_show+0xfd/0x170 [ 79.711642] [] ? seq_read+0x4b6/0x12d0 [ 79.717166] [] ? do_loop_readv_writev.part.1+0xd5/0x280 [ 79.724238] [] ? do_readv_writev+0x56e/0x7b0 [ 79.730269] [] ? vfs_readv+0x84/0xc0 [ 79.735617] [] ? do_preadv+0x197/0x240 [ 79.741128] [] ? SyS_preadv+0x30/0x40 [ 79.746558] [] lock_acquire+0x130/0x3e0 [ 79.752153] [] ? lock_trace+0x44/0xc0 [ 79.757578] [] mutex_lock_killable_nested+0xcc/0x960 [ 79.764314] [] ? lock_trace+0x44/0xc0 [ 79.769767] [] ? lock_trace+0x44/0xc0 [ 79.775190] [] ? check_preemption_disabled+0x3b/0x170 [ 79.782002] [] ? _mutex_lock_nest_lock+0x870/0x870 [ 79.788565] [] ? kasan_unpoison_shadow+0x35/0x50 [ 79.794941] [] ? kasan_kmalloc+0xaf/0xc0 [ 79.800901] [] lock_trace+0x44/0xc0 [ 79.806165] [] proc_pid_stack+0xdc/0x220 [ 79.811847] [] ? lock_trace+0xc0/0xc0 [ 79.817270] [] ? get_pid_task+0x9b/0x140 [ 79.822953] [] proc_single_show+0xfd/0x170 [ 79.828809] [] seq_read+0x4b6/0x12d0 [ 79.834141] [] ? seq_lseek+0x3c0/0x3c0 [ 79.839649] [] ? __fsnotify_inode_delete+0x30/0x30 [ 79.846200] [] ? __fsnotify_update_child_dentry_flags.part.0+0x300/0x300 [ 79.854662] [] do_loop_readv_writev.part.1+0xd5/0x280 [ 79.861472] [] do_readv_writev+0x56e/0x7b0 [ 79.867331] [] ? vfs_write+0x520/0x520 [ 79.872844] [] ? _raw_spin_unlock_irqrestore+0x45/0x70 [ 79.879743] [] ? debug_check_no_obj_freed+0x2ce/0x890 [ 79.886556] [] ? __fd_install+0x20f/0x5d0 [ 79.892325] [] ? check_preemption_disabled+0x3b/0x170 [ 79.899137] [] ? check_preemption_disabled+0x3b/0x170 [ 79.905949] [] ? __fget+0x214/0x3d0 [ 79.911197] [] ? __fget+0x23b/0x3d0 [ 79.916445] [] ? __fget+0x47/0x3d0 [ 79.921615] [] vfs_readv+0x84/0xc0 [ 79.926780] [] do_preadv+0x197/0x240 [ 79.932116] [] ? do_readv+0x260/0x260 [ 79.937541] [] ? compat_SyS_vmsplice+0x160/0x160 [ 79.943917] [] SyS_preadv+0x30/0x40 [ 79.949167] [] ? SyS_writev+0x30/0x30 [ 79.954589] [] do_syscall_64+0x19f/0x480 [ 79.960306] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb 2018/09/23 08:03:34 executed programs: 3134 2018/09/23 08:03:39 executed programs: 3672