Merge "futex: Ensure the correct return value from futex_lock_pi()" (41d44701) · Commits · e / devices / android_kernel_oneplus_sm7250

kernel/futex.c

+18 −18

Original line number	Diff line number	Diff line
		@@ -2411,8 +2411,8 @@ static int fixup_pi_state_owner(u32 __user uaddr, struct futex_q q,
		}

		if (__rt_mutex_futex_trylock(&pi_state->pi_mutex)) {
		/* We got the lock after all, nothing to fix. */
		ret = 0;
		/* We got the lock. pi_state is correct. Tell caller. */
		ret = 1;
		goto out_unlock;
		}

		@@ -2440,7 +2440,7 @@ static int fixup_pi_state_owner(u32 __user uaddr, struct futex_q q,
		* We raced against a concurrent self; things are
		* already fixed up. Nothing to do.
		*/
		ret = 0;
		ret = 1;
		goto out_unlock;
		}
		newowner = argowner;
		@@ -2486,7 +2486,7 @@ static int fixup_pi_state_owner(u32 __user uaddr, struct futex_q q,
		raw_spin_unlock(&newowner->pi_lock);
		raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock);

		return 0;
		return argowner == current;

		/*
		* In order to reschedule or handle a page fault, we need to drop the
		@@ -2528,7 +2528,7 @@ static int fixup_pi_state_owner(u32 __user uaddr, struct futex_q q,
		* Check if someone else fixed it for us:
		*/
		if (pi_state->owner != oldowner) {
		ret = 0;
		ret = argowner == current;
		goto out_unlock;
		}

		@@ -2561,8 +2561,6 @@ static long futex_wait_restart(struct restart_block *restart);
		*/
		static int fixup_owner(u32 __user uaddr, struct futex_q q, int locked)
		{
		int ret = 0;

		if (locked) {
		/*
		* Got the lock. We might not be the anticipated owner if we
		@@ -2573,8 +2571,8 @@ static int fixup_owner(u32 __user uaddr, struct futex_q q, int locked)
		* stable state, anything else needs more attention.
		*/
		if (q->pi_state->owner != current)
		ret = fixup_pi_state_owner(uaddr, q, current);
		goto out;
		return fixup_pi_state_owner(uaddr, q, current);
		return 1;
		}

		/*
		@@ -2585,24 +2583,21 @@ static int fixup_owner(u32 __user uaddr, struct futex_q q, int locked)
		* Another speculative read; pi_state->owner == current is unstable
		* but needs our attention.
		*/
		if (q->pi_state->owner == current) {
		ret = fixup_pi_state_owner(uaddr, q, NULL);
		goto out;
		}
		if (q->pi_state->owner == current)
		return fixup_pi_state_owner(uaddr, q, NULL);

		/*
		* Paranoia check. If we did not take the lock, then we should not be
		* the owner of the rt_mutex.
		*/
		if (rt_mutex_owner(&q->pi_state->pi_mutex) == current) {
		printk(KERN_ERR "fixup_owner: ret = %d pi-mutex: %p "
		"pi-state %p\n", ret,
		printk(KERN_ERR "fixup_owner: pi-mutex: %p "
		"pi-state %p\n",
		q->pi_state->pi_mutex.owner,
		q->pi_state->owner);
		}

		out:
		return ret ? ret : locked;
		return 0;
		}

		/**
		@@ -3324,7 +3319,7 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
		if (q.pi_state && (q.pi_state->owner != current)) {
		spin_lock(q.lock_ptr);
		ret = fixup_pi_state_owner(uaddr2, &q, current);
		if (ret && rt_mutex_owner(&q.pi_state->pi_mutex) == current) {
		if (ret < 0 && rt_mutex_owner(&q.pi_state->pi_mutex) == current) {
		pi_state = q.pi_state;
		get_pi_state(pi_state);
		}
		@@ -3334,6 +3329,11 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags,
		*/
		put_pi_state(q.pi_state);
		spin_unlock(q.lock_ptr);
		/*
		* Adjust the return value. It's either -EFAULT or
		* success (1) but the caller expects 0 for success.
		*/
		ret = ret < 0 ? ret : 0;
		}
		} else {
		struct rt_mutex *pi_mutex;