Fix CVE-2025-62229: xorg-x11-server: Use-after-free in XPresentNotify structures creation

Resolves: RHEL-119989 Fix CVE-2025-62230: xorg-x11-server: Use-after-free in Xkb client resource removal Resolves: RHEL-120009 Fix CVE-2025-62231: xorg-x11-server: Value overflow in Xkb extension XkbSetCompatMap() Resolves: RHEL-120770
2025-10-31 10:06:59 +01:00 · 2025-10-31 10:06:59 +01:00 · d815f4c4c9
commit d815f4c4c9
parent 8e02c2f3a3
5 changed files with 296 additions and 1 deletions
--- a/tigervnc.spec
+++ b/tigervnc.spec
@ -5,7 +5,7 @@

 Name:           tigervnc
 Version:        1.15.0
-Release:        5%{?dist}
+Release:        7%{?dist}
 Summary:        A TigerVNC remote display system

 %global _hardened_build 1
@ -398,6 +398,16 @@ fi
 %ghost %verify(not md5 size mode mtime) %{_sharedstatedir}/selinux/%{selinuxtype}/active/modules/200/%{modulename}

 %changelog
+* Fri Oct 31 2025 Jan Grulich <jgrulich@redhat.com> - 1.15.0-7
+- Fix CVE-2025-62229: xorg-x11-server: Use-after-free in XPresentNotify structures creation
+  Resolves: RHEL-119989
+
+- Fix CVE-2025-62230: xorg-x11-server: Use-after-free in Xkb client resource removal
+  Resolves: RHEL-120009
+
+- Fix CVE-2025-62231: xorg-x11-server: Value overflow in Xkb extension XkbSetCompatMap()
+  Resolves: RHEL-120770
+
 * Mon Jun 23 2025 Jan Grulich <jgrulich@redhat.com> - 1.15.0-5
 - Fix CVE-2025-49175: xorg-x11-server: Out-of-Bounds Read in X Rendering Extension Animated Cursors
  Resolves: RHEL-97284
--- a/xorg-CVE-2025-62229.patch
+++ b/xorg-CVE-2025-62229.patch
@ -0,0 +1,88 @@
+From 4d07b16328bc9c9d4f6c4c1a9a522d64bf09deda Mon Sep 17 00:00:00 2001
+From: Olivier Fourdan <ofourdan@redhat.com>
+Date: Wed, 2 Jul 2025 09:46:22 +0200
+Subject: [PATCH xserver 1/4] present: Fix use-after-free in
+ present_create_notifies()
+
+Using the Present extension, if an error occurs while processing and
+adding the notifications after presenting a pixmap, the function
+present_create_notifies() will clean up and remove the notifications
+it added.
+
+However, there are two different code paths that can lead to an error
+creating the notify, one being before the notify is being added to the
+list, and another one after the notify is added.
+
+When the error occurs before it's been added, it removes the elements up
+to the last added element, instead of the actual number of elements
+which were added.
+
+As a result, in case of error, as with an invalid window for example, it
+leaves a dangling pointer to the last element, leading to a use after
+free case later:
+
+ |  Invalid write of size 8
+ |     at 0x5361D5: present_clear_window_notifies (present_notify.c:42)
+ |     by 0x534A56: present_destroy_window (present_screen.c:107)
+ |     by 0x41E441: xwl_destroy_window (xwayland-window.c:1959)
+ |     by 0x4F9EC9: compDestroyWindow (compwindow.c:622)
+ |     by 0x51EAC4: damageDestroyWindow (damage.c:1592)
+ |     by 0x4FDC29: DbeDestroyWindow (dbe.c:1291)
+ |     by 0x4EAC55: FreeWindowResources (window.c:1023)
+ |     by 0x4EAF59: DeleteWindow (window.c:1091)
+ |     by 0x4DE59A: doFreeResource (resource.c:890)
+ |     by 0x4DEFB2: FreeClientResources (resource.c:1156)
+ |     by 0x4A9AFB: CloseDownClient (dispatch.c:3567)
+ |     by 0x5DCC78: ClientReady (connection.c:603)
+ |   Address 0x16126200 is 16 bytes inside a block of size 2,048 free'd
+ |     at 0x4841E43: free (vg_replace_malloc.c:989)
+ |     by 0x5363DD: present_destroy_notifies (present_notify.c:111)
+ |     by 0x53638D: present_create_notifies (present_notify.c:100)
+ |     by 0x5368E9: proc_present_pixmap_common (present_request.c:164)
+ |     by 0x536A7D: proc_present_pixmap (present_request.c:189)
+ |     by 0x536FA9: proc_present_dispatch (present_request.c:337)
+ |     by 0x4A1E4E: Dispatch (dispatch.c:561)
+ |     by 0x4B00F1: dix_main (main.c:284)
+ |     by 0x42879D: main (stubmain.c:34)
+ |   Block was alloc'd at
+ |     at 0x48463F3: calloc (vg_replace_malloc.c:1675)
+ |     by 0x5362A1: present_create_notifies (present_notify.c:81)
+ |     by 0x5368E9: proc_present_pixmap_common (present_request.c:164)
+ |     by 0x536A7D: proc_present_pixmap (present_request.c:189)
+ |     by 0x536FA9: proc_present_dispatch (present_request.c:337)
+ |     by 0x4A1E4E: Dispatch (dispatch.c:561)
+ |     by 0x4B00F1: dix_main (main.c:284)
+ |     by 0x42879D: main (stubmain.c:34)
+
+To fix the issue, count and remove the actual number of notify elements
+added in case of error.
+
+CVE-2025-62229, ZDI-CAN-27238
+
+This vulnerability was discovered by:
+Jan-Niklas Sohn working with Trend Micro Zero Day Initiative
+
+Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
+(cherry picked from commit 5a4286b13f631b66c20f5bc8db7b68211dcbd1d0)
+
+Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2088>
+---
+ present/present_notify.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/present/present_notify.c b/present/present_notify.c
+index 445954998..00b3b68bd 100644
+--- a/present/present_notify.c
+++ b/present/present_notify.c
+@@ -90,7 +90,7 @@ present_create_notifies(ClientPtr client, int num_notifies, xPresentNotify *x_no
+         if (status != Success)
+             goto bail;
+ 
+-        added = i;
+        added++;
+     }
+     return Success;
+ 
+-- 
+2.51.1
+
--- a/xorg-CVE-2025-62230-1.patch
+++ b/xorg-CVE-2025-62230-1.patch
@ -0,0 +1,59 @@
+From a1d4f04bbd46957af854bea3b23d0dcb31b38afd Mon Sep 17 00:00:00 2001
+From: Olivier Fourdan <ofourdan@redhat.com>
+Date: Wed, 10 Sep 2025 15:55:06 +0200
+Subject: [PATCH xserver 2/4] xkb: Make the RT_XKBCLIENT resource private
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Currently, the resource in only available to the xkb.c source file.
+
+In preparation for the next commit, to be able to free the resources
+from XkbRemoveResourceClient(), make that variable private instead.
+
+This is related to:
+
+CVE-2025-62230, ZDI-CAN-27545
+
+This vulnerability was discovered by:
+Jan-Niklas Sohn working with Trend Micro Zero Day Initiative
+
+Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
+Reviewed-by: Michel Dänzer <mdaenzer@redhat.com>
+(cherry picked from commit 99790a2c9205a52fbbec01f21a92c9b7f4ed1d8f)
+
+Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2088>
+---
+ include/xkbsrv.h | 2 ++
+ xkb/xkb.c        | 2 +-
+ 2 files changed, 3 insertions(+), 1 deletion(-)
+
+diff --git a/include/xkbsrv.h b/include/xkbsrv.h
+index bd747856b..d801cd4b8 100644
+--- a/include/xkbsrv.h
+++ b/include/xkbsrv.h
+@@ -58,6 +58,8 @@ THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ #include "inputstr.h"
+ #include "events.h"
+ 
+extern RESTYPE RT_XKBCLIENT;
+
+ typedef struct _XkbInterest {
+     DeviceIntPtr dev;
+     ClientPtr client;
+diff --git a/xkb/xkb.c b/xkb/xkb.c
+index ac154e200..6c102af0a 100644
+--- a/xkb/xkb.c
+++ b/xkb/xkb.c
+@@ -50,7 +50,7 @@ int XkbKeyboardErrorCode;
+ CARD32 xkbDebugFlags = 0;
+ static CARD32 xkbDebugCtrls = 0;
+ 
+-static RESTYPE RT_XKBCLIENT;
+RESTYPE RT_XKBCLIENT = 0;
+ 
+ /***====================================================================***/
+ 
+-- 
+2.51.1
+
--- a/xorg-CVE-2025-62230-2.patch
+++ b/xorg-CVE-2025-62230-2.patch
@ -0,0 +1,89 @@
+From 1abca0b9b5b019cda32aa92466a760660ebd952d Mon Sep 17 00:00:00 2001
+From: Olivier Fourdan <ofourdan@redhat.com>
+Date: Wed, 10 Sep 2025 15:58:57 +0200
+Subject: [PATCH xserver 3/4] xkb: Free the XKB resource when freeing
+ XkbInterest
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+XkbRemoveResourceClient() would free the XkbInterest data associated
+with the device, but not the resource associated with it.
+
+As a result, when the client terminates, the resource delete function
+gets called and accesses already freed memory:
+
+ | Invalid read of size 8
+ |   at 0x5BC0C0: XkbRemoveResourceClient (xkbEvents.c:1047)
+ |   by 0x5B3391: XkbClientGone (xkb.c:7094)
+ |   by 0x4DF138: doFreeResource (resource.c:890)
+ |   by 0x4DFB50: FreeClientResources (resource.c:1156)
+ |   by 0x4A9A59: CloseDownClient (dispatch.c:3550)
+ |   by 0x5E0A53: ClientReady (connection.c:601)
+ |   by 0x5E4FEF: ospoll_wait (ospoll.c:657)
+ |   by 0x5DC834: WaitForSomething (WaitFor.c:206)
+ |   by 0x4A1BA5: Dispatch (dispatch.c:491)
+ |   by 0x4B0070: dix_main (main.c:277)
+ |   by 0x4285E7: main (stubmain.c:34)
+ | Address 0x1893e278 is 184 bytes inside a block of size 928 free'd
+ |   at 0x4842E43: free (vg_replace_malloc.c:989)
+ |   by 0x49C1A6: CloseDevice (devices.c:1067)
+ |   by 0x49C522: CloseOneDevice (devices.c:1193)
+ |   by 0x49C6E4: RemoveDevice (devices.c:1244)
+ |   by 0x5873D4: remove_master (xichangehierarchy.c:348)
+ |   by 0x587921: ProcXIChangeHierarchy (xichangehierarchy.c:504)
+ |   by 0x579BF1: ProcIDispatch (extinit.c:390)
+ |   by 0x4A1D85: Dispatch (dispatch.c:551)
+ |   by 0x4B0070: dix_main (main.c:277)
+ |   by 0x4285E7: main (stubmain.c:34)
+ | Block was alloc'd at
+ |   at 0x48473F3: calloc (vg_replace_malloc.c:1675)
+ |   by 0x49A118: AddInputDevice (devices.c:262)
+ |   by 0x4A0E58: AllocDevicePair (devices.c:2846)
+ |   by 0x5866EE: add_master (xichangehierarchy.c:153)
+ |   by 0x5878C2: ProcXIChangeHierarchy (xichangehierarchy.c:493)
+ |   by 0x579BF1: ProcIDispatch (extinit.c:390)
+ |   by 0x4A1D85: Dispatch (dispatch.c:551)
+ |   by 0x4B0070: dix_main (main.c:277)
+ |   by 0x4285E7: main (stubmain.c:34)
+
+To avoid that issue, make sure to free the resources when freeing the
+device XkbInterest data.
+
+CVE-2025-62230, ZDI-CAN-27545
+
+This vulnerability was discovered by:
+Jan-Niklas Sohn working with Trend Micro Zero Day Initiative
+
+Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
+Reviewed-by: Michel Dänzer <mdaenzer@redhat.com>
+(cherry picked from commit 10c94238bdad17c11707e0bdaaa3a9cd54c504be)
+
+Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2088>
+---
+ xkb/xkbEvents.c | 2 ++
+ 1 file changed, 2 insertions(+)
+
+diff --git a/xkb/xkbEvents.c b/xkb/xkbEvents.c
+index f8f65d4a7..7c669c93e 100644
+--- a/xkb/xkbEvents.c
+++ b/xkb/xkbEvents.c
+@@ -1055,6 +1055,7 @@ XkbRemoveResourceClient(DevicePtr inDev, XID id)
+             autoCtrls = interest->autoCtrls;
+             autoValues = interest->autoCtrlValues;
+             client = interest->client;
+            FreeResource(interest->resource, RT_XKBCLIENT);
+             free(interest);
+             found = TRUE;
+         }
+@@ -1066,6 +1067,7 @@ XkbRemoveResourceClient(DevicePtr inDev, XID id)
+                 autoCtrls = victim->autoCtrls;
+                 autoValues = victim->autoCtrlValues;
+                 client = victim->client;
+                FreeResource(victim->resource, RT_XKBCLIENT);
+                 free(victim);
+                 found = TRUE;
+             }
+-- 
+2.51.1
+
--- a/xorg-CVE-2025-62231.patch
+++ b/xorg-CVE-2025-62231.patch
@ -0,0 +1,49 @@
+From c7beaec76c556870e5566b84dce7099bf28f9502 Mon Sep 17 00:00:00 2001
+From: Olivier Fourdan <ofourdan@redhat.com>
+Date: Wed, 10 Sep 2025 16:30:29 +0200
+Subject: [PATCH xserver 4/4] xkb: Prevent overflow in XkbSetCompatMap()
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+The XkbCompatMap structure stores its "num_si" and "size_si" fields
+using an unsigned short.
+
+However, the function _XkbSetCompatMap() will store the sum of the
+input data "firstSI" and "nSI" in both XkbCompatMap's "num_si" and
+"size_si" without first checking if the sum overflows the maximum
+unsigned short value, leading to a possible overflow.
+
+To avoid the issue, check whether the sum does not exceed the maximum
+unsigned short value, or return a "BadValue" error otherwise.
+
+CVE-2025-62231, ZDI-CAN-27560
+
+This vulnerability was discovered by:
+Jan-Niklas Sohn working with Trend Micro Zero Day Initiative
+
+Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
+Reviewed-by: Michel Dänzer <mdaenzer@redhat.com>
+(cherry picked from commit 475d9f49acd0e55bc0b089ed77f732ad18585470)
+
+Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/2088>
+---
+ xkb/xkb.c | 2 ++
+ 1 file changed, 2 insertions(+)
+
+diff --git a/xkb/xkb.c b/xkb/xkb.c
+index 6c102af0a..a77fe7ff0 100644
+--- a/xkb/xkb.c
+++ b/xkb/xkb.c
+@@ -2990,6 +2990,8 @@ _XkbSetCompatMap(ClientPtr client, DeviceIntPtr dev,
+         XkbSymInterpretPtr sym;
+         unsigned int skipped = 0;
+ 
+        if ((unsigned) (req->firstSI + req->nSI) > USHRT_MAX)
+            return BadValue;
+         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,
+-- 
+2.51.1
+