diff mbox series

[scarthgap,7/8] libxml2: Fix CVE-2026-86143

Message ID 20260929041836.2217090-7-hthakar@cisco.com
State New
Headers show
Series [scarthgap,1/8] libxml2: Fix CVE-2026-86137 | expand

Commit Message

Hetvi Thakar -X (hthakar - E INFOCHIPS PRIVATE LIMITED at Cisco) Sept. 29, 2026, 4:18 a.m. UTC 
From: Hetvi Thakar <hthakar@cisco.com>

This patch applies the upstream fix as referenced in [2],
using the commit shown in [1].

[1] https://github.com/GNOME/libxml2/commit/90f293ba74d28b1d570920382e707586f68ebf35
[2] https://nvd.nist.gov/vuln/detail/CVE-2026-86143

Signed-off-by: Hetvi Thakar <hthakar@cisco.com>
---
 .../libxml/libxml2/CVE-2026-86143.patch       | 91 +++++++++++++++++++
 meta/recipes-core/libxml/libxml2_2.12.10.bb   |  1 +
 2 files changed, 92 insertions(+)
 create mode 100644 meta/recipes-core/libxml/libxml2/CVE-2026-86143.patch
diff mbox series

Patch

diff --git a/meta/recipes-core/libxml/libxml2/CVE-2026-86143.patch b/meta/recipes-core/libxml/libxml2/CVE-2026-86143.patch
new file mode 100644
index 0000000000..228b5136bb
--- /dev/null
+++ b/meta/recipes-core/libxml/libxml2/CVE-2026-86143.patch
@@ -0,0 +1,91 @@ 
+From 83259eee08067b547d2aaedd436504939b2c343b Mon Sep 17 00:00:00 2001
+From: Daniel Garcia Moreno <daniel.garcia@suse.com>
+Date: Mon, 4 May 2026 09:54:34 +0200
+Subject: [PATCH] xmlIO: Check for int overflow before calling writecallback
+
+Fix https://gitlab.gnome.org/GNOME/libxml2/-/work_items/1111
+
+CVE: CVE-2026-86143
+Upstream-Status: Backport [https://github.com/GNOME/libxml2/commit/90f293ba74d28b1d570920382e707586f68ebf35]
+
+Backport Changes:
+- Change nbchars to size_t in both Scarthgap write functions before assigning the size_t result of xmlBufUse(). Add the INT_MAX guard to both xmlOutputBufferWrite() callback paths. The upstream commit assumes earlier refactoring that changed nbchars to size_t and routed xmlOutputBufferWriteEscape() through the protected write path; the existing flush guards are retained.
+
+(cherry picked from commit 90f293ba74d28b1d570920382e707586f68ebf35)
+Signed-off-by: Hetvi Thakar <hthakar@cisco.com>
+---
+ xmlIO.c | 26 ++++++++++++++++++----
+ 1 file changed, 22 insertions(+), 4 deletions(-)
+
+diff --git a/xmlIO.c b/xmlIO.c
+index 95d27157..de227d8c 100644
+--- a/xmlIO.c
++++ b/xmlIO.c
+@@ -3318,7 +3318,7 @@
+  */
+ int
+ xmlOutputBufferWrite(xmlOutputBufferPtr out, int len, const char *buf) {
+-    int nbchars = 0; /* number of chars to output to I/O */
++    size_t nbchars = 0; /* number of chars to output to I/O */
+     int ret;         /* return from function call */
+     int written = 0; /* number of char written to I/O so far */
+     int chunk;       /* number of byte current processed from buf */
+@@ -3378,6 +3378,10 @@
+             if ((nbchars < MINLEN) && (len <= 0))
+                 goto done;
+ 
++            if (nbchars >= INT_MAX) {
++                out->error = XML_ERR_INTERNAL_ERROR;
++                return(-1);
++            }
+ 	    /*
+ 	     * second write the stuff to the I/O channel
+ 	     */
+@@ -3487,7 +3491,7 @@
+ int
+ xmlOutputBufferWriteEscape(xmlOutputBufferPtr out, const xmlChar *str,
+                            xmlCharEncodingOutputFunc escaping) {
+-    int nbchars = 0; /* number of chars to output to I/O */
++    size_t nbchars = 0; /* number of chars to output to I/O */
+     int ret;         /* return from function call */
+     int written = 0; /* number of char written to I/O so far */
+     int oldwritten=0;/* loop guard */
+@@ -3572,6 +3576,10 @@
+             if ((nbchars < MINLEN) && (len <= 0))
+                 goto done;
+ 
++            if (nbchars >= INT_MAX) {
++                out->error = XML_ERR_INTERNAL_ERROR;
++                return(-1);
++            }
+ 	    /*
+ 	     * second write the stuff to the I/O channel
+ 	     */
+@@ -3667,15 +3675,25 @@
+      */
+     if ((out->conv != NULL) && (out->encoder != NULL) &&
+ 	(out->writecallback != NULL)) {
++        size_t bufsize = xmlBufUse(out->conv);
++        if (bufsize >= INT_MAX) {
++            out->error = XML_ERR_INTERNAL_ERROR;
++            return(-1);
++        }
+ 	ret = out->writecallback(out->context,
+                                  (const char *)xmlBufContent(out->conv),
+-                                 xmlBufUse(out->conv));
++                                 bufsize);
+ 	if (ret >= 0)
+ 	    xmlBufShrink(out->conv, ret);
+     } else if (out->writecallback != NULL) {
++        size_t bufsize = xmlBufUse(out->buffer);
++        if (bufsize >= INT_MAX) {
++            out->error = XML_ERR_INTERNAL_ERROR;
++            return(-1);
++        }
+ 	ret = out->writecallback(out->context,
+                                  (const char *)xmlBufContent(out->buffer),
+-                                 xmlBufUse(out->buffer));
++                                 bufsize);
+ 	if (ret >= 0)
+ 	    xmlBufShrink(out->buffer, ret);
+     }
diff --git a/meta/recipes-core/libxml/libxml2_2.12.10.bb b/meta/recipes-core/libxml/libxml2_2.12.10.bb
index 881b60133d..1b0c3d50da 100644
--- a/meta/recipes-core/libxml/libxml2_2.12.10.bb
+++ b/meta/recipes-core/libxml/libxml2_2.12.10.bb
@@ -37,6 +37,7 @@  SRC_URI += "http://www.w3.org/XML/Test/xmlts20130923.tar;subdir=${BP};name=testt
            file://CVE-2026-86140.patch \
            file://CVE-2026-86141.patch \
            file://CVE-2026-86142.patch \
+           file://CVE-2026-86143.patch \
            "
 
 SRC_URI[archive.sha256sum] = "c3d8c0c34aa39098f66576fe51969db12a5100b956233dc56506f7a8679be995"