======================================================
WARNING: possible circular locking dependency detected
4.14.99+ #13 Not tainted
------------------------------------------------------
syz-executor.1/7946 is trying to acquire lock:
(&p->lock){+.+.}, at: [<ffffffff8f9cd68d>] seq_read+0xcd/0x1180 fs/seq_file.c:165
but task is already holding lock:
(&pipe->mutex/1){+.+.}, at: [<ffffffff8f96fa58>] pipe_lock_nested fs/pipe.c:67 [inline]
(&pipe->mutex/1){+.+.}, at: [<ffffffff8f96fa58>] pipe_lock+0x58/0x70 fs/pipe.c:75
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (&pipe->mutex/1){+.+.}:
-> #1 (&sig->cred_guard_mutex){+.+.}:
-> #0 (&p->lock){+.+.}:
other info that might help us debug this:
Chain exists of:
&p->lock --> &sig->cred_guard_mutex --> &pipe->mutex/1
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&pipe->mutex/1);
lock(&sig->cred_guard_mutex);
lock(&pipe->mutex/1);
lock(&p->lock);
*** DEADLOCK ***
1 lock held by syz-executor.1/7946:
#0: (&pipe->mutex/1){+.+.}, at: [<ffffffff8f96fa58>] pipe_lock_nested fs/pipe.c:67 [inline]
#0: (&pipe->mutex/1){+.+.}, at: [<ffffffff8f96fa58>] pipe_lock+0x58/0x70 fs/pipe.c:75
stack backtrace:
CPU: 0 PID: 7946 Comm: syz-executor.1 Not tainted 4.14.99+ #13
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
audit: type=1400 audit(2000000073.800:52): avc: denied { map } for pid=8053 comm="syz-executor.4" path="socket:[23874]" dev="sockfs" ino=23874 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=packet_socket permissive=1
EXT4-fs warning (device sda1): ext4_block_to_path:105: block 1313565906 > max in inode 17159
EXT4-fs warning (device sda1): ext4_block_to_path:105: block 1313565906 > max in inode 17159
EXT4-fs warning (device sda1): ext4_block_to_path:105: block 1313565906 > max in inode 16558
EXT4-fs warning (device sda1): ext4_block_to_path:105: block 1313565906 > max in inode 16546
EXT4-fs warning (device sda1): ext4_block_to_path:105: block 1313565906 > max in inode 16559
EXT4-fs warning (device sda1): ext4_block_to_path:105: block 1313565906 > max in inode 16542
EXT4-fs warning (device sda1): ext4_block_to_path:105: block 1313565906 > max in inode 16559
EXT4-fs warning (device sda1): ext4_block_to_path:105: block 1313565906 > max in inode 16559
audit: type=1400 audit(2000000001.570:53): avc: denied { map } for pid=8599 comm="syz-executor.2" path="/dev/net/tun" dev="devtmpfs" ino=1070 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:tun_tap_device_t:s0 tclass=chr_file permissive=1