======================================================
WARNING: possible circular locking dependency detected
4.14.96+ #19 Not tainted
------------------------------------------------------
syz-executor5/466 is trying to acquire lock:
(&p->lock){+.+.}, at: [<ffffffffb7dcca2d>] seq_read+0xcd/0x1180 fs/seq_file.c:165
but task is already holding lock:
(&pipe->mutex/1){+.+.}, at: [<ffffffffb7d6ede8>] pipe_lock_nested fs/pipe.c:67 [inline]
(&pipe->mutex/1){+.+.}, at: [<ffffffffb7d6ede8>] 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-executor5/466:
#0: (&pipe->mutex/1){+.+.}, at: [<ffffffffb7d6ede8>] pipe_lock_nested fs/pipe.c:67 [inline]
#0: (&pipe->mutex/1){+.+.}, at: [<ffffffffb7d6ede8>] pipe_lock+0x58/0x70 fs/pipe.c:75
stack backtrace:
CPU: 0 PID: 466 Comm: syz-executor5 Not tainted 4.14.96+ #19
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
kauditd_printk_skb: 350 callbacks suppressed
audit: type=1400 audit(1548537791.550:71502): avc: denied { map } for pid=518 comm="blkid" path="/lib/x86_64-linux-gnu/libc-2.13.so" dev="sda1" ino=2784 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
audit: type=1400 audit(1548537791.550:71503): avc: denied { map } for pid=519 comm="modprobe" path="/lib/x86_64-linux-gnu/libc-2.13.so" dev="sda1" ino=2784 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
audit: type=1400 audit(1548537791.550:71504): avc: denied { map } for pid=519 comm="modprobe" path="/lib/x86_64-linux-gnu/libc-2.13.so" dev="sda1" ino=2784 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
audit: type=1400 audit(1548537791.620:71505): avc: denied { map } for pid=518 comm="blkid" path="/lib/x86_64-linux-gnu/libuuid.so.1.3.0" dev="sda1" ino=2819 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
audit: type=1400 audit(1548537791.620:71506): avc: denied { map } for pid=518 comm="blkid" path="/lib/x86_64-linux-gnu/libuuid.so.1.3.0" dev="sda1" ino=2819 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
audit: type=1400 audit(1548537791.680:71507): avc: denied { read } for pid=509 comm="syz-executor4" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_generic_socket permissive=1
audit: type=1400 audit(1548537792.120:71508): avc: denied { create } for pid=537 comm="syz-executor4" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_generic_socket permissive=1
audit: type=1400 audit(1548537792.130:71509): avc: denied { write } for pid=537 comm="syz-executor4" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_generic_socket permissive=1
audit: type=1400 audit(1548537792.180:71510): avc: denied { map } for pid=541 comm="blkid" path="/sbin/blkid" dev="sda1" ino=16128 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
audit: type=1400 audit(1548537792.190:71511): avc: denied { map } for pid=541 comm="blkid" path="/sbin/blkid" dev="sda1" ino=16128 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
kauditd_printk_skb: 321 callbacks suppressed
audit: type=1400 audit(1548537796.570:71833): avc: denied { create } for pid=726 comm="syz-executor4" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_generic_socket permissive=1
audit: type=1400 audit(1548537796.570:71834): avc: denied { write } for pid=726 comm="syz-executor4" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_generic_socket permissive=1
audit: type=1400 audit(1548537796.570:71835): avc: denied { map } for pid=728 comm="modprobe" path="/bin/kmod" dev="sda1" ino=1440 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
audit: type=1400 audit(1548537796.570:71836): avc: denied { map } for pid=728 comm="modprobe" path="/bin/kmod" dev="sda1" ino=1440 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
audit: type=1400 audit(1548537796.570:71837): avc: denied { map } for pid=728 comm="modprobe" path="/lib/x86_64-linux-gnu/ld-2.13.so" dev="sda1" ino=2668 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
audit: type=1400 audit(1548537796.570:71838): avc: denied { map } for pid=728 comm="modprobe" path="/lib/x86_64-linux-gnu/ld-2.13.so" dev="sda1" ino=2668 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
audit: type=1400 audit(1548537796.570:71839): avc: denied { map } for pid=728 comm="modprobe" path="/etc/ld.so.cache" dev="sda1" ino=2503 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
audit: type=1400 audit(1548537796.570:71840): avc: denied { map } for pid=728 comm="modprobe" path="/lib/x86_64-linux-gnu/libkmod.so.2.1.3" dev="sda1" ino=2811 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
audit: type=1400 audit(1548537796.570:71841): avc: denied { map } for pid=728 comm="modprobe" path="/lib/x86_64-linux-gnu/libkmod.so.2.1.3" dev="sda1" ino=2811 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
audit: type=1400 audit(1548537796.600:71842): avc: denied { map } for pid=728 comm="modprobe" path="/lib/x86_64-linux-gnu/libc-2.13.so" dev="sda1" ino=2784 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1