xserver-xorg: backport fixes for CVE-2022-3550 and CVE-2022-3551

Signed-off-by: Ross Burton <ross.burton@arm.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

3 files changed, 103 insertions, 0 deletions

diff --git a/meta/recipes-graphics/xorg-xserver/xserver-xorg/0001-xkb-fix-some-possible-memleaks-in-XkbGetKbdByName.patch b/meta/recipes-graphics/xorg-xserver/xserver-xorg/0001-xkb-fix-some-possible-memleaks-in-XkbGetKbdByName.patch
new file mode 100644
index 0000000000..0e61ec5953
--- /dev/null
+++ b/meta/recipes-graphics/xorg-xserver/xserver-xorg/0001-xkb-fix-some-possible-memleaks-in-XkbGetKbdByName.patch
@@ -0,0 +1,63 @@
+CVE: CVE-2022-3551
+Upstream-Status: Backport
+Signed-off-by: Ross Burton <ross.burton@arm.com>
+
+From 18f91b950e22c2a342a4fbc55e9ddf7534a707d2 Mon Sep 17 00:00:00 2001
+From: Peter Hutterer <peter.hutterer@who-t.net>
+Date: Wed, 13 Jul 2022 11:23:09 +1000
+Subject: [PATCH] xkb: fix some possible memleaks in XkbGetKbdByName
+
+GetComponentByName returns an allocated string, so let's free that if we
+fail somewhere.
+
+Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
+---
+ xkb/xkb.c | 26 ++++++++++++++++++++------
+ 1 file changed, 20 insertions(+), 6 deletions(-)
+
+diff --git a/xkb/xkb.c b/xkb/xkb.c
+index 4692895db..b79a269e3 100644
+--- a/xkb/xkb.c
++++ b/xkb/xkb.c
+@@ -5935,18 +5935,32 @@ ProcXkbGetKbdByName(ClientPtr client)
+     xkb = dev->key->xkbInfo->desc;
+     status = Success;
+     str = (unsigned char *) &stuff[1];
+-    if (GetComponentSpec(&str, TRUE, &status))  /* keymap, unsupported */
+-        return BadMatch;
++    {
++        char *keymap = GetComponentSpec(&str, TRUE, &status);  /* keymap, unsupported */
++        if (keymap) {
++            free(keymap);
++            return BadMatch;
++        }
++    }
+     names.keycodes = GetComponentSpec(&str, TRUE, &status);
+     names.types = GetComponentSpec(&str, TRUE, &status);
+     names.compat = GetComponentSpec(&str, TRUE, &status);
+     names.symbols = GetComponentSpec(&str, TRUE, &status);
+     names.geometry = GetComponentSpec(&str, TRUE, &status);
+-    if (status != Success)
++    if (status == Success) {
++        len = str - ((unsigned char *) stuff);
++        if ((XkbPaddedSize(len) / 4) != stuff->length)
++            status = BadLength;
++    }
++
++    if (status != Success) {
++        free(names.keycodes);
++        free(names.types);
++        free(names.compat);
++        free(names.symbols);
++        free(names.geometry);
+         return status;
+-    len = str - ((unsigned char *) stuff);
+-    if ((XkbPaddedSize(len) / 4) != stuff->length)
+-        return BadLength;
++    }
+ 
+     CHK_MASK_LEGAL(0x01, stuff->want, XkbGBN_AllComponentsMask);
+     CHK_MASK_LEGAL(0x02, stuff->need, XkbGBN_AllComponentsMask);
+-- 
+2.34.1
+
diff --git a/meta/recipes-graphics/xorg-xserver/xserver-xorg/0001-xkb-proof-GetCountedString-against-request-length-at.patch b/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/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
+
diff --git a/meta/recipes-graphics/xorg-xserver/xserver-xorg_21.1.4.bb b/meta/recipes-graphics/xorg-xserver/xserver-xorg_21.1.4.bb
index b9cbc9989e..aba09afec3 100644
--- a/meta/recipes-graphics/xorg-xserver/xserver-xorg_21.1.4.bb
+++ b/meta/recipes-graphics/xorg-xserver/xserver-xorg_21.1.4.bb
@@ -2,6 +2,8 @@ require xserver-xorg.inc
 
 SRC_URI += "file://0001-xf86pciBus.c-use-Intel-ddx-only-for-pre-gen4-hardwar.patch \
            file://0001-Avoid-duplicate-definitions-of-IOPortBase.patch \
+           file://0001-xkb-fix-some-possible-memleaks-in-XkbGetKbdByName.patch \
+           file://0001-xkb-proof-GetCountedString-against-request-length-at.patch \
            "
 SRC_URI[sha256sum] = "5cc4be8ee47edb58d4a90e603a59d56b40291ad38371b0bd2471fc3cbee1c587"