Added early return in WebCore::TextResourceDecoder::checkForCSSCharset to fix buffer overflow

Source/core/html/parser/TextResourceDecoder.cpp

Index: Source/core/html/parser/TextResourceDecoder.cpp
diff --git a/Source/core/html/parser/TextResourceDecoder.cpp b/Source/core/html/parser/TextResourceDecoder.cpp
index 3daddfedb413d5f0d67bb83ca336ece74ad782c3..493f5cbddb93f522493d866625ebc019c2153022 100644
--- a/Source/core/html/parser/TextResourceDecoder.cpp
+++ b/Source/core/html/parser/TextResourceDecoder.cpp
@@ -264,6 +264,8 @@ bool TextResourceDecoder::checkForCSSCharset(const char* data, size_t len, bool&
         int encodingNameLength = pos - dataStart;
 
         ++pos;
+        if (pos == dataEnd)

[eseidel, 2014/05/28 00:42:51]

Seems like we should wrap this in a helper which returns pos != dataEnd, but OK.

+            return false;
 
         if (*pos == ';')
             setEncoding(findTextEncoding(dataStart, encodingNameLength), EncodingFromCSSCharset);