116 lines
3.4 KiB
Diff
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
|
|
|