diff --git a/kernel/futex.c b/kernel/futex.c index 1dc98e4dd287ec95872c7c771aab7f14e0d9ca42..cf0c8e21d1abaae85c17a816dbd42a8ed3132dd5 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -476,6 +476,12 @@ lookup_pi_state(u32 uval, struct futex_hash_bucket *hb, struct futex_q *me) * the refcount and return its pi_state: */ pi_state = this->pi_state; + /* + * Userspace might have messed up non PI and PI futexes + */ + if (unlikely(!pi_state)) + return -EINVAL; + atomic_inc(&pi_state->refcount); me->pi_state = pi_state;