Update from debian/bullseye-security for apertis/v2024dev1

debian/patches/13_Xtest-disallow-GenericEvents-in-XTestSwapFakeInput.patch

+From: Peter Hutterer <peter.hutterer@who-t.net>
+Date: Tue, 29 Nov 2022 12:55:45 +1000
+Subject: Xtest: disallow GenericEvents in XTestSwapFakeInput
+Origin: https://gitlab.freedesktop.org/xorg/xserver/commit/936d34bdff4c479ccd0405fc221ff8e4c6c7014d
+Bug-Debian-Security: https://security-tracker.debian.org/tracker/CVE-2022-46340
+Bug-Debian: https://bugs.debian.org/1026071
+
+XTestSwapFakeInput assumes all events in this request are
+sizeof(xEvent) and iterates through these in 32-byte increments.
+However, a GenericEvent may be of arbitrary length longer than 32 bytes,
+so any GenericEvent in this list would result in subsequent events to be
+misparsed.
+
+Additional, the swapped event is written into a stack-allocated struct
+xEvent (size 32 bytes). For any GenericEvent longer than 32 bytes,
+swapping the event may thus smash the stack like an avocado on toast.
+
+Catch this case early and return BadValue for any GenericEvent.
+Which is what would happen in unswapped setups anyway since XTest
+doesn't support GenericEvent.
+
+CVE-2022-46340, ZDI-CAN 19265
+
+This vulnerability was discovered by:
+Jan-Niklas Sohn working with Trend Micro Zero Day Initiative
+
+Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
+Acked-by: Olivier Fourdan <ofourdan@redhat.com>
+(cherry picked from commit b320ca0ffe4c0c872eeb3a93d9bde21f765c7c63)
+---
+ Xext/xtest.c | 5 +++--
+ 1 file changed, 3 insertions(+), 2 deletions(-)
+
+diff --git a/Xext/xtest.c b/Xext/xtest.c
+index 540d270a1c0d..e5d38aa61253 100644
+--- a/Xext/xtest.c
++++ b/Xext/xtest.c
+@@ -502,10 +502,11 @@ XTestSwapFakeInput(ClientPtr client, xReq * req)
+ 
+     nev = ((req->length << 2) - sizeof(xReq)) / sizeof(xEvent);
+     for (ev = (xEvent *) &req[1]; --nev >= 0; ev++) {
++        int evtype = ev->u.u.type & 0x177;
+         /* Swap event */
+-        proc = EventSwapVector[ev->u.u.type & 0177];
++        proc = EventSwapVector[evtype];
+         /* no swapping proc; invalid event type? */
+-        if (!proc || proc == NotImplemented) {
++        if (!proc || proc == NotImplemented || evtype == GenericEvent) {
+             client->errorValue = ev->u.u.type;
+             return BadValue;
+         }
+-- 
+2.39.0
+