xorg-x11-server-Xwayland/0005-Xi-flush-hierarchy-events-after-adding-removing-mast.patch
Olivier Fourdan 23869c61c1 CVE fixes
Fix for CVE-2023-6816, CVE-2024-0229, CVE-2024-21885, CVE-2024-21886,
CVE-2024-0408, CVE-2024-0409

Resolves: https://issues.redhat.com/browse/RHEL-20379
Resolves: https://issues.redhat.com/browse/RHEL-20385
Resolves: https://issues.redhat.com/browse/RHEL-20529
Resolves: https://issues.redhat.com/browse/RHEL-21194
Resolves: https://issues.redhat.com/browse/RHEL-21204
Resolves: https://issues.redhat.com/browse/RHEL-21211
2024-01-16 16:09:12 +01:00

112 lines
3.5 KiB
Diff

From 7efd09cdb13ae1a4100f68a11947afe581fa1ee8 Mon Sep 17 00:00:00 2001
From: Peter Hutterer <peter.hutterer@who-t.net>
Date: Thu, 4 Jan 2024 10:01:24 +1000
Subject: [PATCH xserver 5/9] Xi: flush hierarchy events after adding/removing
master devices
The `XISendDeviceHierarchyEvent()` function allocates space to store up
to `MAXDEVICES` (256) `xXIHierarchyInfo` structures in `info`.
If a device with a given ID was removed and a new device with the same
ID added both in the same operation, the single device ID will lead to
two info structures being written to `info`.
Since this case can occur for every device ID at once, a total of two
times `MAXDEVICES` info structures might be written to the allocation.
To avoid it, once one add/remove master is processed, send out the
device hierarchy event for the current state and continue. That event
thus only ever has exactly one of either added/removed in it (and
optionally slave attached/detached).
CVE-2024-21885, ZDI-CAN-22744
This vulnerability was discovered by:
Jan-Niklas Sohn working with Trend Micro Zero Day Initiative
(cherry picked from commit 4a5e9b1895627d40d26045bd0b7ef3dce503cbd1)
---
Xi/xichangehierarchy.c | 27 ++++++++++++++++++++++-----
1 file changed, 22 insertions(+), 5 deletions(-)
diff --git a/Xi/xichangehierarchy.c b/Xi/xichangehierarchy.c
index d2d985848..72d00451e 100644
--- a/Xi/xichangehierarchy.c
+++ b/Xi/xichangehierarchy.c
@@ -416,6 +416,11 @@ ProcXIChangeHierarchy(ClientPtr client)
size_t len; /* length of data remaining in request */
int rc = Success;
int flags[MAXDEVICES] = { 0 };
+ enum {
+ NO_CHANGE,
+ FLUSH,
+ CHANGED,
+ } changes = NO_CHANGE;
REQUEST(xXIChangeHierarchyReq);
REQUEST_AT_LEAST_SIZE(xXIChangeHierarchyReq);
@@ -465,8 +470,9 @@ ProcXIChangeHierarchy(ClientPtr client)
rc = add_master(client, c, flags);
if (rc != Success)
goto unwind;
- }
+ changes = FLUSH;
break;
+ }
case XIRemoveMaster:
{
xXIRemoveMasterInfo *r = (xXIRemoveMasterInfo *) any;
@@ -475,8 +481,9 @@ ProcXIChangeHierarchy(ClientPtr client)
rc = remove_master(client, r, flags);
if (rc != Success)
goto unwind;
- }
+ changes = FLUSH;
break;
+ }
case XIDetachSlave:
{
xXIDetachSlaveInfo *c = (xXIDetachSlaveInfo *) any;
@@ -485,8 +492,9 @@ ProcXIChangeHierarchy(ClientPtr client)
rc = detach_slave(client, c, flags);
if (rc != Success)
goto unwind;
- }
+ changes = CHANGED;
break;
+ }
case XIAttachSlave:
{
xXIAttachSlaveInfo *c = (xXIAttachSlaveInfo *) any;
@@ -495,16 +503,25 @@ ProcXIChangeHierarchy(ClientPtr client)
rc = attach_slave(client, c, flags);
if (rc != Success)
goto unwind;
+ changes = CHANGED;
+ break;
}
+ default:
break;
}
+ if (changes == FLUSH) {
+ XISendDeviceHierarchyEvent(flags);
+ memset(flags, 0, sizeof(flags));
+ changes = NO_CHANGE;
+ }
+
len -= any->length * 4;
any = (xXIAnyHierarchyChangeInfo *) ((char *) any + any->length * 4);
}
unwind:
-
- XISendDeviceHierarchyEvent(flags);
+ if (changes != NO_CHANGE)
+ XISendDeviceHierarchyEvent(flags);
return rc;
}
--
2.43.0