audit: type=1400 audit(1548023970.321:47215): avc: denied { read open } for pid=23110 comm="syz-executor3" path="/dev/input/event0" dev="devtmpfs" ino=5414 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=chr_file permissive=1 ====================================================== WARNING: possible circular locking dependency detected 4.14.94+ #12 Not tainted ------------------------------------------------------ syz-executor0/23122 is trying to acquire lock: (&sig->cred_guard_mutex){+.+.}, at: [] lock_trace+0x3f/0xc0 fs/proc/base.c:408 but task is already holding lock: (&p->lock){+.+.}, at: [] seq_read+0xcd/0x1180 fs/seq_file.c:165 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&p->lock){+.+.}: -> #1 (&pipe->mutex/1){+.+.}: -> #0 (&sig->cred_guard_mutex){+.+.}: other info that might help us debug this: Chain exists of: &sig->cred_guard_mutex --> &pipe->mutex/1 --> &p->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&p->lock); lock(&pipe->mutex/1); lock(&p->lock); lock(&sig->cred_guard_mutex); *** DEADLOCK *** 1 lock held by syz-executor0/23122: #0: (&p->lock){+.+.}, at: [] seq_read+0xcd/0x1180 fs/seq_file.c:165 stack backtrace: CPU: 0 PID: 23122 Comm: syz-executor0 Not tainted 4.14.94+ #12 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: 83 callbacks suppressed audit: type=1400 audit(1548023975.811:47299): avc: denied { read } for pid=23173 comm="syz-executor4" name="event0" dev="devtmpfs" ino=5414 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=chr_file permissive=1 audit: type=1400 audit(1548023975.841:47300): avc: denied { read } for pid=23171 comm="syz-executor3" name="event0" dev="devtmpfs" ino=5414 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=chr_file permissive=1 audit: type=1400 audit(1548023975.841:47301): avc: denied { read open } for pid=23171 comm="syz-executor3" path="/dev/input/event0" dev="devtmpfs" ino=5414 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=chr_file permissive=1 audit: type=1400 audit(1548023975.871:47302): avc: denied { map } for pid=23170 comm="syz-executor1" path="/root/syzkaller-testdir878866134/syzkaller.siBuRu/673/file1" dev="sda1" ino=17587 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 audit: type=1400 audit(1548023975.881:47303): avc: denied { read open } for pid=23173 comm="syz-executor4" path="/dev/input/event0" dev="devtmpfs" ino=5414 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=chr_file permissive=1 audit: type=1400 audit(1548023975.881:47304): avc: denied { ioctl } for pid=23171 comm="syz-executor3" path="/dev/input/event0" dev="devtmpfs" ino=5414 ioctlcmd=0x4504 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=chr_file permissive=1 audit: type=1400 audit(1548023975.901:47305): avc: denied { read } for pid=23171 comm="syz-executor3" name="event0" dev="devtmpfs" ino=5414 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=chr_file permissive=1 audit: type=1400 audit(1548023975.911:47306): avc: denied { read open } for pid=23171 comm="syz-executor3" path="/dev/input/event0" dev="devtmpfs" ino=5414 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=chr_file permissive=1 audit: type=1400 audit(1548023975.961:47307): avc: denied { ioctl } for pid=23171 comm="syz-executor3" path="/dev/input/event0" dev="devtmpfs" ino=5414 ioctlcmd=0x4504 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=chr_file permissive=1 audit: type=1400 audit(1548023976.081:47308): avc: denied { map } for pid=23182 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