proc: unrecognized mount option "./file0" or missing value audit: type=1400 audit(1551828781.240:135): avc: denied { map } for pid=702 comm="syz-executor.3" path="/dev/zero" dev="sda1" ino=2638 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=chr_file permissive=1 ====================================================== WARNING: possible circular locking dependency detected 4.14.105+ #24 Not tainted ------------------------------------------------------ syz-executor.5/717 is trying to acquire lock: (&pipe->mutex/1){+.+.}, at: [] __pipe_lock fs/pipe.c:88 [inline] (&pipe->mutex/1){+.+.}, at: [] fifo_open+0x156/0x9b0 fs/pipe.c:921 but task is already holding lock: (&sig->cred_guard_mutex){+.+.}, at: [] prepare_bprm_creds+0x51/0x110 fs/exec.c:1389 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&sig->cred_guard_mutex){+.+.}: -> #0 (&pipe->mutex/1){+.+.}: other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sig->cred_guard_mutex); lock(&pipe->mutex/1); lock(&sig->cred_guard_mutex); lock(&pipe->mutex/1); *** DEADLOCK *** 1 lock held by syz-executor.5/717: #0: (&sig->cred_guard_mutex){+.+.}, at: [] prepare_bprm_creds+0x51/0x110 fs/exec.c:1389 stack backtrace: CPU: 1 PID: 717 Comm: syz-executor.5 Not tainted 4.14.105+ #24 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xb9/0x10e lib/dump_stack.c:53 print_circular_bug.isra.0.cold+0x2dc/0x425 kernel/locking/lockdep.c:1258 proc: unrecognized mount option "./file0" or missing value proc: unrecognized mount option "./file0" or missing value proc: unrecognized mount option "./file0" or missing value proc: unrecognized mount option "./file0" or missing value proc: unrecognized mount option "./file0" or missing value proc: unrecognized mount option "./file0" or missing value proc: unrecognized mount option "./file0" or missing value proc: unrecognized mount option "./file0" or missing value proc: unrecognized mount option "./file0" or missing value proc: unrecognized mount option "./file0" or missing value proc: unrecognized mount option "./file0" or missing value proc: unrecognized mount option "./file0" or missing value proc: unrecognized mount option "./file0" or missing value proc: unrecognized mount option "./file0" or missing value proc: unrecognized mount option "./file0" or missing value proc: unrecognized mount option "./file0" or missing value ip6_tunnel: ip6tnl1 xmit: Local address not yet configured! proc: unrecognized mount option "./file0" or missing value