From ded614e74e7175927dd2bc5ef69accaf2de29939 Mon Sep 17 00:00:00 2001 From: Peter Hutterer Date: Wed, 4 Dec 2024 15:49:43 +1000 Subject: [PATCH xserver 2/2] dix: keep a ref to the rootCursor CreateCursor returns a cursor with refcount 1 - that refcount is used by the resource system, any caller needs to call RefCursor to get their own reference. That happens correctly for normal cursors but for our rootCursor we keep a variable to the cursor despite not having a ref for ourselves. Fix this by reffing/unreffing the rootCursor to ensure our pointer is valid. Related to CVE-2025-26594, ZDI-CAN-25544 Reviewed-by: Olivier Fourdan --- dix/main.c | 4 ++++ 1 file changed, 4 insertions(+) Index: xorg-server-21.1.14/dix/main.c =================================================================== --- xorg-server-21.1.14.orig/dix/main.c +++ xorg-server-21.1.14/dix/main.c @@ -233,6 +233,8 @@ dix_main(int argc, char *argv[], char *e FatalError("could not open default cursor font"); } + rootCursor = RefCursor(rootCursor); + #ifdef PANORAMIX /* * Consolidate window and colourmap information for each screen @@ -275,6 +277,8 @@ dix_main(int argc, char *argv[], char *e Dispatch(); + UnrefCursor(rootCursor); + UndisplayDevices(); DisableAllDevices();