From d132ecb1402dde84ce9851bddaa6587a90014e07 Mon Sep 17 00:00:00 2001
From: wk333 <13474090681@163.com>
Date: Tue, 17 Dec 2024 15:44:15 +0800
Subject: [PATCH 1/1] Fix heap-buffer overflow

Refer: https://sourceforge.net/u/mmuzila/giflib/ci/fix-cve-2022-28506/

---
 gif2rgb.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/gif2rgb.c b/gif2rgb.c
index 2b4bb23..0b2e05a 100644
--- a/gif2rgb.c
+++ b/gif2rgb.c
@@ -337,6 +337,11 @@ static void DumpScreen2RGB(char *FileName, int OneFileFlag,
 			GifRow = ScreenBuffer[i];
 			GifQprintf("\b\b\b\b%-4d", ScreenHeight - i);
 			for (j = 0; j < ScreenWidth; j++) {
+				/* Check if color is within color palete */
+				if (GifRow[j] >= ColorMap->ColorCount) {
+					GIF_EXIT(GifErrorString(
+					    D_GIF_ERR_IMAGE_DEFECT));
+				}
 				ColorMapEntry = &ColorMap->Colors[GifRow[j]];
 				Buffers[0][j] = ColorMapEntry->Red;
 				Buffers[1][j] = ColorMapEntry->Green;
-- 
2.33.0