LibAudio: Prevent int overflow in the user buffer queue

The `UserSampleQueue::remaining_samples` calculates the result by
subtracting two unsigned int numbers. That can lead to integer overflow.
Add an assert to verify that the minuend is greater or equal to the
subtrahend.

1 files changed, 1 insertions, 0 deletions

diff --git a/Userland/Libraries/LibAudio/UserSampleQueue.cpp b/Userland/Libraries/LibAudio/UserSampleQueue.cpp
index f58601849a..020cafb8b1 100644
--- a/Userland/Libraries/LibAudio/UserSampleQueue.cpp
+++ b/Userland/Libraries/LibAudio/UserSampleQueue.cpp
@@ -51,6 +51,7 @@ size_t UserSampleQueue::size()
 size_t UserSampleQueue::remaining_samples()
 {
     Threading::MutexLocker lock(m_sample_mutex);
+    VERIFY(m_backing_samples.size() >= m_samples_to_discard);
     return m_backing_samples.size() - m_samples_to_discard;
 }