random: sshd: uninitialized urandom read (32 bytes read) random: sshd: uninitialized urandom read (32 bytes read) random: sshd: uninitialized urandom read (32 bytes read) audit: type=1400 audit(1553261604.682:7): avc: denied { map } for pid=1779 comm="syz-executor600" path="/root/syz-executor600393421" dev="sda1" ino=16482 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 ====================================================== WARNING: possible circular locking dependency detected 4.14.107+ #33 Not tainted ------------------------------------------------------ syz-executor600/1779 is trying to acquire lock: (&cpuctx_mutex/1){+.+.}, at: [] mutex_lock_double kernel/events/core.c:9907 [inline] (&cpuctx_mutex/1){+.+.}, at: [] __perf_event_ctx_lock_double kernel/events/core.c:9966 [inline] (&cpuctx_mutex/1){+.+.}, at: [] SYSC_perf_event_open kernel/events/core.c:10231 [inline] (&cpuctx_mutex/1){+.+.}, at: [] SyS_perf_event_open+0x11f1/0x2520 kernel/events/core.c:9986 but task is already holding lock: (&cpuctx_mutex){+.+.}, at: [] mutex_lock_double kernel/events/core.c:9906 [inline] (&cpuctx_mutex){+.+.}, at: [] __perf_event_ctx_lock_double kernel/events/core.c:9966 [inline] (&cpuctx_mutex){+.+.}, at: [] SYSC_perf_event_open kernel/events/core.c:10231 [inline] (&cpuctx_mutex){+.+.}, at: [] SyS_perf_event_open+0x11e4/0x2520 kernel/events/core.c:9986 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&cpuctx_mutex){+.+.}: -> #1 (pmus_lock){+.+.}: -> #0 (&cpuctx_mutex/1){+.+.}: other info that might help us debug this: Chain exists of: &cpuctx_mutex/1 --> pmus_lock --> &cpuctx_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&cpuctx_mutex); lock(pmus_lock); lock(&cpuctx_mutex); lock(&cpuctx_mutex/1); *** DEADLOCK *** 1 lock held by syz-executor600/1779: #0: (&cpuctx_mutex){+.+.}, at: [] mutex_lock_double kernel/events/core.c:9906 [inline] #0: (&cpuctx_mutex){+.+.}, at: [] __perf_event_ctx_lock_double kernel/events/core.c:9966 [inline] #0: (&cpuctx_mutex){+.+.}, at: [] SYSC_perf_event_open kernel/events/core.c:10231 [inline] #0: (&cpuctx_mutex){+.+.}, at: [] SyS_perf_event_open+0x11e4/0x2520 kernel/events/core.c:9986 stack backtrace: CPU: 0 PID: 1779 Comm: syz-executor600 Not tainted 4.14.107+ #33 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 ? SyS_perf_event_open+