tigervnc/SOURCES/xorg-CVE-2025-26598.patch
eabdullin ac18fd1e56 - Fix CVE-2025-26594 xorg-x11-server Use-after-free of the root cursor
- Fix CVE-2025-26595 xorg-x11-server Buffer overflow in XkbVModMaskText()
- Fix CVE-2025-26596 xorg-x11-server Heap overflow in XkbWriteKeySyms()
- Fix CVE-2025-26597 xorg-x11-server Buffer overflow in XkbChangeTypesOfKey()
- Fix CVE-2025-26598 xorg-x11-server Out-of-bounds write in CreatePointerBarrierClient()
- Fix CVE-2025-26599 xorg-x11-server Use of uninitialized pointer in compRedirectWindow()
- Fix CVE-2025-26600 xorg-x11-server Use-after-free in PlayReleasedEvents()
- Fix CVE-2025-26601 xorg-x11-server Use-after-free in SyncInitTrigger()
2025-04-01 12:09:24 +03:00

116 lines
3.4 KiB
Diff

From 0f5ea9d269ac6225bcb302a1ec0f58878114da9f Mon Sep 17 00:00:00 2001
From: Olivier Fourdan <ofourdan@redhat.com>
Date: Mon, 16 Dec 2024 11:25:11 +0100
Subject: [PATCH xserver] Xi: Fix barrier device search
The function GetBarrierDevice() would search for the pointer device
based on its device id and return the matching value, or supposedly NULL
if no match was found.
Unfortunately, as written, it would return the last element of the list
if no matching device id was found which can lead to out of bounds
memory access.
Fix the search function to return NULL if not matching device is found,
and adjust the callers to handle the case where the device cannot be
found.
CVE-2025-26598, ZDI-CAN-25740
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: Peter Hutterer <peter.hutterer@who-t.net>
---
Xi/xibarriers.c | 27 +++++++++++++++++++++++----
1 file changed, 23 insertions(+), 4 deletions(-)
diff --git a/Xi/xibarriers.c b/Xi/xibarriers.c
index 80c4b5981..28bc0a24f 100644
--- a/Xi/xibarriers.c
+++ b/Xi/xibarriers.c
@@ -131,14 +131,15 @@ static void FreePointerBarrierClient(struct PointerBarrierClient *c)
static struct PointerBarrierDevice *GetBarrierDevice(struct PointerBarrierClient *c, int deviceid)
{
- struct PointerBarrierDevice *pbd = NULL;
+ struct PointerBarrierDevice *p, *pbd = NULL;
- xorg_list_for_each_entry(pbd, &c->per_device, entry) {
- if (pbd->deviceid == deviceid)
+ xorg_list_for_each_entry(p, &c->per_device, entry) {
+ if (p->deviceid == deviceid) {
+ pbd = p;
break;
+ }
}
- BUG_WARN(!pbd);
return pbd;
}
@@ -339,6 +340,9 @@ barrier_find_nearest(BarrierScreenPtr cs, DeviceIntPtr dev,
double distance;
pbd = GetBarrierDevice(c, dev->id);
+ if (!pbd)
+ continue;
+
if (pbd->seen)
continue;
@@ -447,6 +451,9 @@ input_constrain_cursor(DeviceIntPtr dev, ScreenPtr screen,
nearest = &c->barrier;
pbd = GetBarrierDevice(c, master->id);
+ if (!pbd)
+ continue;
+
new_sequence = !pbd->hit;
pbd->seen = TRUE;
@@ -487,6 +494,9 @@ input_constrain_cursor(DeviceIntPtr dev, ScreenPtr screen,
int flags = 0;
pbd = GetBarrierDevice(c, master->id);
+ if (!pbd)
+ continue;
+
pbd->seen = FALSE;
if (!pbd->hit)
continue;
@@ -681,6 +691,9 @@ BarrierFreeBarrier(void *data, XID id)
continue;
pbd = GetBarrierDevice(c, dev->id);
+ if (!pbd)
+ continue;
+
if (!pbd->hit)
continue;
@@ -740,6 +753,8 @@ static void remove_master_func(void *res, XID id, void *devid)
barrier = container_of(b, struct PointerBarrierClient, barrier);
pbd = GetBarrierDevice(barrier, *deviceid);
+ if (!pbd)
+ return;
if (pbd->hit) {
BarrierEvent ev = {
@@ -904,6 +919,10 @@ ProcXIBarrierReleasePointer(ClientPtr client)
barrier = container_of(b, struct PointerBarrierClient, barrier);
pbd = GetBarrierDevice(barrier, dev->id);
+ if (!pbd) {
+ client->errorValue = dev->id;
+ return BadDevice;
+ }
if (pbd->barrier_event_id == event_id)
pbd->release_event_id = event_id;
--
2.48.1