Warning: Permanently added '10.128.0.32' (ECDSA) to the list of known hosts. [ 34.484187] urandom_read: 1 callbacks suppressed [ 34.484190] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 34.583637] audit: type=1400 audit(1538210857.017:7): avc: denied { map } for pid=1788 comm="syz-executor387" path="/root/syz-executor387661542" dev="sda1" ino=16481 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 [ 34.586790] [ 34.586793] ====================================================== [ 34.586794] WARNING: possible circular locking dependency detected [ 34.586798] 4.14.72+ #11 Not tainted [ 34.586800] ------------------------------------------------------ [ 34.586802] syz-executor387/1788 is trying to acquire lock: [ 34.586804] (&pipe->mutex/1){+.+.}, at: [] fifo_open+0x156/0x9d0 [ 34.586821] [ 34.586821] but task is already holding lock: [ 34.586822] (&sig->cred_guard_mutex){+.+.}, at: [] prepare_bprm_creds+0x4e/0x110 [ 34.586834] [ 34.586834] which lock already depends on the new lock. [ 34.586834] [ 34.586836] [ 34.586836] the existing dependency chain (in reverse order) is: [ 34.586837] [ 34.586837] -> #1 (&sig->cred_guard_mutex){+.+.}: [ 34.586850] __mutex_lock+0xf5/0x1480 [ 34.586858] proc_pid_attr_write+0x16b/0x280 [ 34.586862] __vfs_write+0xf4/0x5c0 [ 34.586866] __kernel_write+0xf3/0x330 [ 34.586871] write_pipe_buf+0x192/0x250 [ 34.586876] __splice_from_pipe+0x324/0x740 [ 34.586880] splice_from_pipe+0xcf/0x130 [ 34.586885] default_file_splice_write+0x37/0x80 [ 34.586890] SyS_splice+0xd06/0x12a0 [ 34.586895] do_syscall_64+0x19b/0x4b0 [ 34.586900] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 34.586901] [ 34.586901] -> #0 (&pipe->mutex/1){+.+.}: [ 34.586912] lock_acquire+0x10f/0x380 [ 34.586917] __mutex_lock+0xf5/0x1480 [ 34.586921] fifo_open+0x156/0x9d0 [ 34.586927] do_dentry_open+0x426/0xda0 [ 34.586932] vfs_open+0x11c/0x210 [ 34.586936] path_openat+0x4eb/0x23a0 [ 34.586941] do_filp_open+0x197/0x270 [ 34.586946] do_open_execat+0x10d/0x5b0 [ 34.586951] do_execveat_common.isra.14+0x6cb/0x1d60 [ 34.586955] SyS_execve+0x34/0x40 [ 34.586959] do_syscall_64+0x19b/0x4b0 [ 34.586964] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 34.586965] [ 34.586965] other info that might help us debug this: [ 34.586965] [ 34.586967] Possible unsafe locking scenario: [ 34.586967] [ 34.586968] CPU0 CPU1 [ 34.586969] ---- ---- [ 34.586970] lock(&sig->cred_guard_mutex); [ 34.586974] lock(&pipe->mutex/1); [ 34.586978] lock(&sig->cred_guard_mutex); [ 34.586981] lock(&pipe->mutex/1); [ 34.586985] [ 34.586985] *** DEADLOCK *** [ 34.586985] [ 34.586988] 1 lock held by syz-executor387/1788: [ 34.586989] #0: (&sig->cred_guard_mutex){+.+.}, at: [] prepare_bprm_creds+0x4e/0x110 [ 34.587013] [ 34.587013] stack backtrace: [ 34.587018] CPU: 0 PID: 1788 Comm: syz-executor387 Not tainted 4.14.72+ #11 [ 34.587020] Call Trace: [ 34.587028] dump_stack+0xb9/0x11b [ 34.587036] print_circular_bug.isra.18.cold.43+0x2d3/0x40c [ 34.587041] ? save_trace+0xd6/0x250 [ 34.587047] __lock_acquire+0x2ff9/0x4320 [ 34.587055] ? check_preemption_disabled+0x34/0x160 [ 34.587064] ? trace_hardirqs_on+0x10/0x10 [ 34.587070] ? trace_hardirqs_on_caller+0x381/0x520 [ 34.587076] ? _raw_spin_unlock_irqrestore+0x41/0x70 [ 34.587084] ? __lock_acquire+0x619/0x4320 [ 34.587089] ? alloc_pipe_info+0x15b/0x370 [ 34.587093] ? fifo_open+0x1ef/0x9d0 [ 34.587097] ? do_dentry_open+0x426/0xda0 [ 34.587102] ? vfs_open+0x11c/0x210 [ 34.587107] ? path_openat+0x4eb/0x23a0 [ 34.587113] lock_acquire+0x10f/0x380 [ 34.587117] ? fifo_open+0x156/0x9d0 [ 34.587124] ? fifo_open+0x156/0x9d0 [ 34.587129] __mutex_lock+0xf5/0x1480 [ 34.587133] ? fifo_open+0x156/0x9d0 [ 34.587138] ? fifo_open+0x156/0x9d0 [ 34.587143] ? dput.part.6+0x3b3/0x710 [ 34.587150] ? __ww_mutex_wakeup_for_backoff+0x240/0x240 [ 34.587158] ? fs_reclaim_acquire+0x10/0x10 [ 34.587165] ? fifo_open+0x284/0x9d0 [ 34.587170] ? lock_downgrade+0x560/0x560 [ 34.587174] ? lock_acquire+0x10f/0x380 [ 34.587179] ? fifo_open+0x243/0x9d0 [ 34.587184] ? debug_mutex_init+0x28/0x53 [ 34.587190] ? fifo_open+0x156/0x9d0 [ 34.587194] fifo_open+0x156/0x9d0 [ 34.587201] do_dentry_open+0x426/0xda0 [ 34.587205] ? pipe_release+0x240/0x240 [ 34.587213] vfs_open+0x11c/0x210 [ 34.587220] path_openat+0x4eb/0x23a0 [ 34.587228] ? path_mountpoint+0x9a0/0x9a0 [ 34.587236] ? kasan_kmalloc.part.1+0xa9/0xd0 [ 34.587242] ? kasan_kmalloc.part.1+0x4f/0xd0 [ 34.587247] ? __kmalloc_track_caller+0x104/0x300 [ 34.587264] ? kmemdup+0x20/0x50 [ 34.587270] ? security_prepare_creds+0x7c/0xb0 [ 34.587276] ? prepare_creds+0x225/0x2a0 [ 34.587281] ? prepare_exec_creds+0xc/0xe0 [ 34.587286] ? prepare_bprm_creds+0x62/0x110 [ 34.587292] ? do_execveat_common.isra.14+0x2cd/0x1d60 [ 34.587297] ? SyS_execve+0x34/0x40 [ 34.587301] ? do_syscall_64+0x19b/0x4b0 [ 34.587309] do_filp_open+0x197/0x270 [ 34.587315] ? may_open_dev+0xd0/0xd0 [ 34.587322] ? trace_hardirqs_on+0x10/0x10 [ 34.587327] ? fs_reclaim_acquire+0x10/0x10 [ 34.587337] ? rcu_read_lock_sched_held+0x102/0x120 [ 34.587344] do_open_execat+0x10d/0x5b0 [ 34.587350] ? setup_arg_pages+0x720/0x720 [ 34.587356] ? do_execveat_common.isra.14+0x68d/0x1d60 [ 34.587361] ? lock_downgrade+0x560/0x560 [ 34.587366] ? lock_acquire+0x10f/0x380 [ 34.587372] ? check_preemption_disabled+0x34/0x160 [ 34.587379] do_execveat_common.isra.14+0x6cb/0x1d60 [ 34.587388] ? prepare_bprm_creds+0x110/0x110 [ 34.587394] ? getname_flags+0x222/0x540 [ 34.587400] SyS_execve+0x34/0x40 [ 34.587405] ? setup_new_exec+0x770/0x770 [ 34.587409] do_syscall_64+0x19b/0x4b0 [ 34.587417] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 34.587420] RIP: 0033:0x440169 [ 34.587423] RSP: 002b:00007fffef9c2748 EFLAGS: 00000217 ORIG_RAX: 000000000000003b [ 34.587429] RAX: ffffffffffffffda RBX: 0030656c69662f2e RCX: 0000000000440169 [ 34.587433] RDX: 00000000200000c0 RSI: 00000000200001c0 RDI: 0000000020ee6ff8 [ 34.587436] RBP: 00000000006cb018 R08: 0000000000000000 R09: 0000000000000000 [ 34.587439] R10: 0000000000000000 R11: 0000000000000217 R12: 00000000004019f0 [ 34.587442] R13: 0000000000401a80 R14: 0000000000000000 R15: 0000000000000000