xserver-xorg: fix CVE-2024-9632

A flaw was found in the X.org server. Due to improperly
tracked allocation size in _XkbSetCompatMap, a local
attacker may be able to trigger a buffer overflow condition
via a specially crafted payload, leading to denial of service
or local privilege escalation in distributions where the
X.org server is run with root privileges.

Reference:
https://nvd.nist.gov/vuln/detail/CVE-2024-9632

Upstream patch:
https://gitlab.freedesktop.org/xorg/xserver/-/commit/ba1d14f8eff2a123bd7ff4d48c02e1d5131358e0

(From OE-Core rev: 95027410dba7a2a7e9b93f76279272f22445399b)

Signed-off-by: Yogita Urade <yogita.urade@windriver.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>

2 files changed, 59 insertions, 0 deletions

diff --git a/meta/recipes-graphics/xorg-xserver/xserver-xorg/CVE-2024-9632.patch b/meta/recipes-graphics/xorg-xserver/xserver-xorg/CVE-2024-9632.patch
new file mode 100644
index 0000000000..387cdaa3c9
--- /dev/null
+++ b/meta/recipes-graphics/xorg-xserver/xserver-xorg/CVE-2024-9632.patch
@@ -0,0 +1,58 @@
+From ba1d14f8eff2a123bd7ff4d48c02e1d5131358e0 Mon Sep 17 00:00:00 2001
+From: Matthieu Herrb <matthieu@herrb.eu>
+Date: Thu, 10 Oct 2024 10:37:28 +0200
+Subject: [PATCH] xkb: Fix buffer overflow in _XkbSetCompatMap()
+
+The _XkbSetCompatMap() function attempts to resize the `sym_interpret`
+buffer.
+
+However, It didn't update its size properly. It updated `num_si` only,
+without updating `size_si`.
+
+This may lead to local privilege escalation if the server is run as root
+or remote code execution (e.g. x11 over ssh).
+
+CVE-2024-9632, ZDI-CAN-24756
+
+This vulnerability was discovered by:
+Jan-Niklas Sohn working with Trend Micro Zero Day Initiative
+
+Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
+Tested-by: Peter Hutterer <peter.hutterer@who-t.net>
+Reviewed-by: José Expósito <jexposit@redhat.com>
+(cherry picked from commit 85b77657)
+
+Part-of: <!1734>
+
+CVE: CVE-2024-9632
+Upstream-Status: Backport [https://gitlab.freedesktop.org/xorg/xserver/-/commit/ba1d14f8eff2a123bd7ff4d48c02e1d5131358e0]
+
+Signed-off-by: Yogita Urade <yogita.urade@windriver.com>
+---
+ xkb/xkb.c | 8 ++++----
+ 1 file changed, 4 insertions(+), 4 deletions(-)
+
+diff --git a/xkb/xkb.c b/xkb/xkb.c
+index 276dc19..7da00a0 100644
+--- a/xkb/xkb.c
++++ b/xkb/xkb.c
+@@ -2992,13 +2992,13 @@ _XkbSetCompatMap(ClientPtr client, DeviceIntPtr dev,
+         XkbSymInterpretPtr sym;
+         unsigned int skipped = 0;
+
+-        if ((unsigned) (req->firstSI + req->nSI) > compat->num_si) {
+-            compat->num_si = req->firstSI + req->nSI;
++        if ((unsigned) (req->firstSI + req->nSI) > compat->size_si) {
++            compat->num_si = compat->size_si = req->firstSI + req->nSI;
+             compat->sym_interpret = reallocarray(compat->sym_interpret,
+-                                                 compat->num_si,
++                                                 compat->size_si,
+                                                  sizeof(XkbSymInterpretRec));
+             if (!compat->sym_interpret) {
+-                compat->num_si = 0;
++                compat->num_si = compat->size_si = 0;
+                 return BadAlloc;
+             }
+         }
+--
+2.40.0
diff --git a/meta/recipes-graphics/xorg-xserver/xserver-xorg_21.1.8.bb b/meta/recipes-graphics/xorg-xserver/xserver-xorg_21.1.8.bb
index fe577050d9..a9cb1b5bde 100644
--- a/meta/recipes-graphics/xorg-xserver/xserver-xorg_21.1.8.bb
+++ b/meta/recipes-graphics/xorg-xserver/xserver-xorg_21.1.8.bb
@@ -21,6 +21,7 @@ SRC_URI += "file://0001-xf86pciBus.c-use-Intel-ddx-only-for-pre-gen4-hardwar.pat
            file://CVE-2024-31082.patch \
            file://CVE-2024-31083-0001.patch \
            file://CVE-2024-31083-0002.patch \
+           file://CVE-2024-9632.patch \
            "
 SRC_URI[sha256sum] = "38aadb735650c8024ee25211c190bf8aad844c5f59632761ab1ef4c4d5aeb152"