[PATCH] libxml2: patch CVE-2026-11979

[Anton Skorup <antonsk@axis.com>]

From: Anton Skorup <anton@skorup.se>

Pick patch from [1] linked from [2].

[1] https://gitlab.gnome.org/GNOME/libxml2/-/commit/c2e233fc1b341685fc99621b2768b503f777a72e
[2] https://gitlab.gnome.org/GNOME/libxml2/-/work_items/1124

Signed-off-by: Anton Skorup <anton.skorup@axis.com>
---
 .../libxml/libxml2/CVE-2026-11979.patch       | 81 +++++++++++++++++++
 meta/recipes-core/libxml/libxml2_2.15.3.bb    |  1 +
 2 files changed, 82 insertions(+)
 create mode 100644 meta/recipes-core/libxml/libxml2/CVE-2026-11979.patch

diff --git a/meta/recipes-core/libxml/libxml2/CVE-2026-11979.patch b/meta/recipes-core/libxml/libxml2/CVE-2026-11979.patch
new file mode 100644
index 0000000000..a14e566681
--- /dev/null
+++ b/meta/recipes-core/libxml/libxml2/CVE-2026-11979.patch
@@ -0,0 +1,81 @@
+From dfad0660f7dab3b5f8317b703b16ad0b0d12697d Mon Sep 17 00:00:00 2001
+From: Daniel Garcia Moreno <daniel.garcia@suse.com>
+Date: Fri, 22 May 2026 12:21:20 +0200
+Subject: [PATCH] xmlcatalog: overflow check for large --shell commands
+
+Fix https://gitlab.gnome.org/GNOME/libxml2/-/work_items/1124
+
+CVE: CVE-2026-11979
+Signed-off-by: Anton Skorup <anton.skorup@axis.com>
+Upstream-Status: Backport [https://gitlab.gnome.org/GNOME/libxml2/-/commit/c2e233fc1b341685fc99621b2768b503f777a72e]
+---
+ test/catalogs/test.sh | 11 +++++++++++
+ xmlcatalog.c          | 16 ++++++++++++++++
+ 2 files changed, 27 insertions(+)
+
+diff --git a/test/catalogs/test.sh b/test/catalogs/test.sh
+index 7e5eaa76..84e8b90a 100755
+--- a/test/catalogs/test.sh
++++ b/test/catalogs/test.sh
+@@ -10,6 +10,17 @@ fi
+ 
+ exitcode=0
+ 
++# Test xmlcatalog --shell command line
++# Case 1: Really long argument (470 chars)
++input=""; for i in {1..470}; do input="${input}A"; done
++echo $input | $xmlcatalog --shell test/catalogs/dockbook.xml || exit 1
++# Case 2: public + long argument
++input="public "; for i in {1..470}; do input="${input}A"; done
++echo $input | $xmlcatalog --shell test/catalogs/dockbook.xml || exit 1
++# Case 3: public + lots of args
++input="public "; for i in {1..80}; do input="${input} x"; done
++echo $input | $xmlcatalog --shell test/catalogs/dockbook.xml || exit 1
++
+ for i in test/catalogs/*.script ; do
+     name=$(basename $i .script)
+     xml="./test/catalogs/$name.xml"
+diff --git a/xmlcatalog.c b/xmlcatalog.c
+index b400c7cb..5113e930 100644
+--- a/xmlcatalog.c
++++ b/xmlcatalog.c
+@@ -135,6 +135,12 @@ static void usershell(void) {
+ 	       (*cur != '\n') && (*cur != '\r')) {
+ 	    if (*cur == 0)
+ 		break;
++            /* Do not read beyond the command array capacity */
++            if (i >= (int)sizeof(command) - 2) {
++                printf("Invalid command %s\n", cur);
++                i = 0;
++                break;
++            }
+ 	    command[i++] = *cur++;
+ 	}
+ 	command[i] = 0;
+@@ -152,6 +158,11 @@ static void usershell(void) {
+ 	while ((*cur != '\n') && (*cur != '\r') && (*cur != 0)) {
+ 	    if (*cur == 0)
+ 		break;
++            if (i >= (int)sizeof(arg) - 2) {
++                printf("Invalid arg %s\n", arg);
++                i = 0;
++                break;
++            }
+ 	    arg[i++] = *cur++;
+ 	}
+ 	arg[i] = 0;
+@@ -164,6 +175,11 @@ static void usershell(void) {
+ 	cur = arg;
+ 	memset(argv, 0, sizeof(argv));
+ 	while (*cur != 0) {
++            if (i >= (int)sizeof(argv) / (int)sizeof(char*)) {
++                printf("Too much arguments\n");
++                break;
++            }
++
+ 	    while ((*cur == ' ') || (*cur == '\t')) cur++;
+ 	    if (*cur == '\'') {
+ 		cur++;
+-- 
+2.43.0
+
diff --git a/meta/recipes-core/libxml/libxml2_2.15.3.bb b/meta/recipes-core/libxml/libxml2_2.15.3.bb
index 3b7a0e3cb5..abf9889b3f 100644
--- a/meta/recipes-core/libxml/libxml2_2.15.3.bb
+++ b/meta/recipes-core/libxml/libxml2_2.15.3.bb
@@ -18,6 +18,7 @@ SRC_URI += "http://www.w3.org/XML/Test/xmlts20130923.tar;subdir=${BP};name=testt
            file://run-ptest \
            file://install-tests.patch \
            file://0001-Revert-cmake-Fix-installation-directories-in-libxml2.patch \
+           file://CVE-2026-11979.patch \
            "
 
 SRC_URI[archive.sha256sum] = "78262a6e7ac170d6528ebfe2efccdf220191a5af6a6cd61ea4a9a9a5042c7a07"
-- 
2.43.0