ieee1394: raw1394: Do not leak memory on failed trylock.

Do not leak the allocated memory in case the mutex_trylock() failed
to acquire the lock.
Signed-off-by: Michael Buesch <mb@bu3sch.de>

This bug does not happen in practice:  All raw1394 clients use
libraw1394, and accesses to a libraw1394 handle need to be serialized
by the client.  This is documented in libraw1394's API reference.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

drivers/ieee1394/raw1394.c

@@ -2272,8 +2272,10 @@ static ssize_t raw1394_write(struct file *file, const char __user * buffer,
 		return -EFAULT;
 	}
 
-	if (!mutex_trylock(&fi->state_mutex))
+	if (!mutex_trylock(&fi->state_mutex)) {
+		free_pending_request(req);
 		return -EAGAIN;
+	}
 
 	switch (fi->state) {
 	case opened: