Merge 94265 - Do more rigorous bounds checking in AudioBufferSourceNode::renderFromBuffer()

Source/WebCore/webaudio/AudioBufferSourceNode.cpp

Index: Source/WebCore/webaudio/AudioBufferSourceNode.cpp
===================================================================
--- Source/WebCore/webaudio/AudioBufferSourceNode.cpp	(revision 94265)
+++ Source/WebCore/webaudio/AudioBufferSourceNode.cpp	(working copy)
@@ -183,6 +183,12 @@
     
     // Sanity check destinationFrameOffset, numberOfFrames.
     size_t destinationLength = bus->length();
+
+    bool isLengthGood = destinationLength <= 4096 && numberOfFrames <= 4096;
+    ASSERT(isLengthGood);
+    if (!isLengthGood)
+        return;
+
     bool isOffsetGood = destinationFrameOffset <= destinationLength && destinationFrameOffset + numberOfFrames <= destinationLength;
     ASSERT(isOffsetGood);
     if (!isOffsetGood)