xserver: Branch 'master'

[GitLab Mirror]

 xkb/xkb.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

New commits:
commit 85b776571487f52e756f68a069c768757369bfe3
Author: Matthieu Herrb <matthieu at herrb.eu>
Date:   Thu Oct 10 10:37:28 2024 +0200

    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 at who-t.net>
    Tested-by: Peter Hutterer <peter.hutterer at who-t.net>
    Reviewed-by: José Expósito <jexposit at redhat.com>
    Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1733>

diff --git a/xkb/xkb.c b/xkb/xkb.c
index 868d7c1e6..aaf9716b3 100644
--- a/xkb/xkb.c
+++ b/xkb/xkb.c
@@ -2990,13 +2990,13 @@ _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;
             }
         }