1 files changed, 38 insertions, 0 deletions
diff --git a/poky/meta/recipes-graphics/xorg-xserver/xserver-xorg/0001-xkb-proof-GetCountedString-against-request-length-at.patch b/poky/meta/recipes-graphics/xorg-xserver/xserver-xorg/0001-xkb-proof-GetCountedString-against-request-length-at.patch
new file mode 100644
index 0000000000..6f862e82f9
--- /dev/null
+++ b/poky/meta/recipes-graphics/xorg-xserver/xserver-xorg/0001-xkb-proof-GetCountedString-against-request-length-at.patch
@@ -0,0 +1,38 @@
+CVE: CVE-2022-3550
+Upstream-Status: Backport
+Signed-off-by: Ross Burton <ross.burton@arm.com>
+
+From 11beef0b7f1ed290348e45618e5fa0d2bffcb72e Mon Sep 17 00:00:00 2001
+From: Peter Hutterer <peter.hutterer@who-t.net>
+Date: Tue, 5 Jul 2022 12:06:20 +1000
+Subject: [PATCH] xkb: proof GetCountedString against request length attacks
+
+GetCountedString did a check for the whole string to be within the
+request buffer but not for the initial 2 bytes that contain the length
+field. A swapped client could send a malformed request to trigger a
+swaps() on those bytes, writing into random memory.
+
+Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
+---
+ xkb/xkb.c | 5 +++++
+ 1 file changed, 5 insertions(+)
+
+diff --git a/xkb/xkb.c b/xkb/xkb.c
+index f42f59ef3..1841cff26 100644
+--- a/xkb/xkb.c
++++ b/xkb/xkb.c
+@@ -5137,6 +5137,11 @@ _GetCountedString(char **wire_inout, ClientPtr client, char **str)
+     CARD16 len;
+ 
+     wire = *wire_inout;
++
++    if (client->req_len <
++        bytes_to_int32(wire + 2 - (char *) client->requestBuffer))
++        return BadValue;
++
+     len = *(CARD16 *) wire;
+     if (client->swapped) {
+         swaps(&len);
+-- 
+2.34.1
+