[oe][meta-oe][wrynose][patch] giflib: Fix CVE-2026-26740

Pick patch according to [2]

[1] https://nvd.nist.gov/vuln/detail/CVE-2026-26740
[2] https://ubuntu.com/security/CVE-2026-26740

Signed-off-by: Vijay Anusuri <[email protected]>
---
 .../giflib/giflib/CVE-2026-26740.patch        | 40 +++++++++++++++++++
 .../recipes-devtools/giflib/giflib_6.1.2.bb   |  1 +
 2 files changed, 41 insertions(+)
 create mode 100644 meta-oe/recipes-devtools/giflib/giflib/CVE-2026-26740.patch

diff --git a/meta-oe/recipes-devtools/giflib/giflib/CVE-2026-26740.patch b/meta-oe/recipes-devtools/giflib/giflib/CVE-2026-26740.patch
new file mode 100644
index 0000000000..14ae97d23f
--- /dev/null
+++ b/meta-oe/recipes-devtools/giflib/giflib/CVE-2026-26740.patch
@@ -0,0 +1,40 @@
+From 061605081115bbfd7019bafc119a13b6f17fcf25 Mon Sep 17 00:00:00 2001
+From: Anthony Hurtado <[email protected]>
+Date: Mon, 1 Jun 2026 15:40:48 -0500
+Subject: [PATCH] Fix CVE-2026-26740: heap OOB write in EGifGCBToSavedExtension
+
+EGifGCBToSavedExtension calls EGifGCBToExtension which unconditionally
+writes 4 bytes into ep->Bytes without checking ep->ByteCount. If the
+extension block was allocated with fewer than 4 bytes, this results in
+a heap buffer overflow.
+
+The read-side counterpart DGifExtensionToGCB already validates that
+GifExtensionLength == 4 before reading. Add the symmetric check on
+the write side: return GIF_ERROR when ep->ByteCount < 4.
+
+Signed-off-by: Anthony Hurtado <[email protected]>
+
+Upstream-Status: Backport [https://sourceforge.net/p/giflib/code/ci/061605081115bbfd7019bafc119a13b6f17fcf25]
+CVE: CVE-2026-26740
+Signed-off-by: Vijay Anusuri <[email protected]>
+---
+ egif_lib.c | 3 +++
+ 1 file changed, 3 insertions(+)
+
+diff --git a/egif_lib.c b/egif_lib.c
+index f1141a2..d74e8df 100644
+--- a/egif_lib.c
++++ b/egif_lib.c
+@@ -690,6 +690,9 @@ int EGifGCBToSavedExtension(const GraphicsControlBlock *GCB,
+ 		ExtensionBlock *ep =
+ 		    &GifFile->SavedImages[ImageIndex].ExtensionBlocks[i];
+ 		if (ep->Function == GRAPHICS_EXT_FUNC_CODE) {
++			if (ep->ByteCount < 4) {
++				return GIF_ERROR;
++			}
+ 			EGifGCBToExtension(GCB, ep->Bytes);
+ 			return GIF_OK;
+ 		}
+-- 
+2.43.0
+
diff --git a/meta-oe/recipes-devtools/giflib/giflib_6.1.2.bb b/meta-oe/recipes-devtools/giflib/giflib_6.1.2.bb
index 9cb2a51879..11f375ef27 100644
--- a/meta-oe/recipes-devtools/giflib/giflib_6.1.2.bb
+++ b/meta-oe/recipes-devtools/giflib/giflib_6.1.2.bb
@@ -9,6 +9,7 @@ DEPENDS = "xmlto-native"
 
 SRC_URI = "${SOURCEFORGE_MIRROR}/giflib/${BP}.tar.gz \
            https://sourceforge.net/p/giflib/code/ci/d54b45b0240d455bbaedee4be5203d2703e59967/tree/doc/giflib-logo.gif?format=raw;subdir=${BP}/doc;name=logo;downloadfilename=giflib-logo.gif \
+           file://CVE-2026-26740.patch \
 "
 
 SRC_URI[logo.sha256sum] = "1a54383986adad1521d00e003b4c482c27e8bc60690be944a1f3319c75abc2c9"
-- 
2.43.0