32764144 Security Vulnerability - heap buffer overflow in libgiftranscode.so
in colorMap->Colors[colorIndex]
* No range checking was done on a color index. Add range
checking and bail if the color index is out of range.
Test: tested sending a large gif that would invoke the GifTranscoder library
to make the gif smaller.
Bug: 32764144
Change-Id: I44f36274ec333ae1960fa8fc96b2dbde35fbaa66
(cherry picked from commit 6f763fef7ab16e28f6c43496e0f866e7803b4dc8)
diff --git a/jni/GifTranscoder.cpp b/jni/GifTranscoder.cpp
index a7f5c74..a3fb5f5 100644
--- a/jni/GifTranscoder.cpp
+++ b/jni/GifTranscoder.cpp
@@ -384,6 +384,11 @@
for (int y = 0; y < gifIn->Image.Height; y++) {
for (int x = 0; x < gifIn->Image.Width; x++) {
GifByteType colorIndex = *getPixel(rasterBits, gifIn->Image.Width, x, y);
+ if (colorIndex >= colorMap->ColorCount) {
+ LOGE("Color Index %d is out of bounds (count=%d)", colorIndex,
+ colorMap->ColorCount);
+ return false;
+ }
// This image may be smaller than the GIF's "logical screen"
int renderX = x + gifIn->Image.Left;
