MatroskaExtractor: detect infinite loop when parsing NALs

Bug: 21335999
Change-Id: I76bd34610e52048ffcf16e41aa6175afc8a14ee4
(cherry picked from commit 2dcf6138)

media/libstagefright/matroska/MatroskaExtractor.cpp

@@ -21,6 +21,7 @@
 #include "MatroskaExtractor.h"
 
 #include <media/stagefright/foundation/ADebug.h>
+#include <media/stagefright/foundation/AUtils.h>
 #include <media/stagefright/foundation/hexdump.h>
 #include <media/stagefright/DataSource.h>
 #include <media/stagefright/MediaBuffer.h>
@@ -631,7 +632,12 @@ status_t MatroskaSource::read(
                     TRESPASS();
             }
 
-            if (srcOffset + mNALSizeLen + NALsize > srcSize) {
+            if (srcOffset + mNALSizeLen + NALsize <= srcOffset + mNALSizeLen) {
+                frame->release();
+                frame = NULL;
+
+                return ERROR_MALFORMED;
+            } else if (srcOffset + mNALSizeLen + NALsize > srcSize) {
                 break;
             }