File 0001-Avoid-potentuial-double-free-on-weird-images.patch of Package giflib

From badbb40d7c1125a15b8908a800bb3642c6086e15 Mon Sep 17 00:00:00 2001
From: "Eric S. Raymond" <esr@thyrsus.com>
Date: Wed, 4 Mar 2026 18:49:49 -0500
Subject: [PATCH] Avoid potentuial double-free on weird images.

---
 gifalloc.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/gifalloc.c b/gifalloc.c
index 47c6539..479c6c5 100644
--- a/gifalloc.c
+++ b/gifalloc.c
@@ -349,6 +349,14 @@ SavedImage *GifMakeSavedImage(GifFileType *GifFile,
 			 * aliasing problems.
 			 */
 
+			/* Null out aliased pointers before any allocations
+			 * so that FreeLastSavedImage won't free CopyFrom's
+			 * data if an allocation fails partway through. */
+			sp->ImageDesc.ColorMap = NULL;
+			sp->RasterBits = NULL;
+			sp->ExtensionBlocks = NULL;
+			sp->ExtensionBlockCount = 0;
+ 
 			/* first, the local color map */
 			if (CopyFrom->ImageDesc.ColorMap != NULL) {
 				sp->ImageDesc.ColorMap = GifMakeMapObject(
-- 
2.53.0