fixup! Fix potential integer overflow at end of stream

wro-ableton · wro-ableton · commit e737e336bff2 · 2024-03-01T16:53:14.000+01:00
diff --git a/audiostream/src/ni/media/audio/os/win/media_foundation_helper.h b/audiostream/src/ni/media/audio/os/win/media_foundation_helper.h
@@ -65,6 +65,8 @@ template <class Source>
 class SyncronousByteStream : public IMFByteStream
 {
 
+    static constexpr auto endOfSequence = -1;
+
     auto tell() -> std::streamsize
     {
         auto pos = m_source.seek( boost::iostreams::stream_offset( 0 ), BOOST_IOS::cur );
@@ -87,7 +89,11 @@ class SyncronousByteStream : public IMFByteStream
         try
         {
             const auto result =  m_source.read( reinterpret_cast<char*>( buffer ), toRead );
-            *read = static_cast<ULONG>( result == -1 ? 0 : result );
+            if(result < endOfSequence)
+            {
+                return E_FAIL;
+            }
+            *read = static_cast<ULONG>( result == endOfSequence ? 0 : result );
             return S_OK;
         }
         catch ( const std::system_error& )

Original file line number	Diff line number	Diff line change
`@@ -65,6 +65,8 @@ template <class Source>`
`65`	`65`	`class SyncronousByteStream : public IMFByteStream`
`66`	`66`	`{`
`67`	`67`
	`68`	`+ static constexpr auto endOfSequence = -1;`
	`69`	`+`
`68`	`70`	`auto tell() -> std::streamsize`
`69`	`71`	`{`
`70`	`72`	`auto pos = m_source.seek( boost::iostreams::stream_offset( 0 ), BOOST_IOS::cur );`
`@@ -87,7 +89,11 @@ class SyncronousByteStream : public IMFByteStream`
`87`	`89`	`try`
`88`	`90`	`{`
`89`	`91`	`const auto result = m_source.read( reinterpret_cast<char*>( buffer ), toRead );`
`90`		`- *read = static_cast<ULONG>( result == -1 ? 0 : result );`
	`92`	`+ if(result < endOfSequence)`
	`93`	`+ {`
	`94`	`+ return E_FAIL;`
	`95`	`+ }`
	`96`	`+ *read = static_cast<ULONG>( result == endOfSequence ? 0 : result );`
`91`	`97`	`return S_OK;`
`92`	`98`	`}`
`93`	`99`	`catch ( const std::system_error& )`