xorg-x11-server-Xwayland/SOURCES/0026-glx-don-t-create-implicit-GLXWindow-if-one-already-e.patch
2021-10-08 18:01:37 +00:00

61 lines
2.6 KiB
Diff

From a604a0a26791e9f352aad27232127d729bca4334 Mon Sep 17 00:00:00 2001
From: Erik Kurzinger <ekurzinger@nvidia.com>
Date: Thu, 10 Dec 2020 14:24:32 -0800
Subject: [PATCH xserver 26/27] glx: don't create implicit GLXWindow if one
already exists
If a GLXMakeCurrent request specifies an X window as its drawable,
__glXGetDrawable will implicitly create a GLXWindow for it. However,
the client may have already explicitly created a GLXWindow for that X
window. If that happens, two __glXDrawableRes resources will be added
to the window.
If the explicitly-created GLXWindow is later destroyed by the client,
DrawableGone will call FreeResourceByType on the X window, but this
will actually free the resource for the implicitly-created GLXWindow,
since that one would be at the head of the list.
Then if the X window is destroyed after that, the resource for the
explicitly-created GLXWindow will be freed. But that GLXWindow was
already destroyed above. This crashes the server when it tries to call
the destroyed GLXWindow's destructor. It also means the
implicitly-created GLXWindow would have been leaked since the
FreeResourceByType call mentioned above skips calling the destructor.
To fix this, if __glXGetDrawable is given an X window, it should check
if there is already a GLXWindow associated with it, and only create an
implicit one if there is not.
Signed-off-by: Erik Kurzinger <ekurzinger@nvidia.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
(cherry picked from commit b7a85e44da91d1663d5b4eabac06327c92a80f91)
---
glx/glxcmds.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/glx/glxcmds.c b/glx/glxcmds.c
index 37576b6ef..1b9ad6d14 100644
--- a/glx/glxcmds.c
+++ b/glx/glxcmds.c
@@ -487,8 +487,15 @@ __glXGetDrawable(__GLXcontext * glxc, GLXDrawable drawId, ClientPtr client,
__GLXscreen *pGlxScreen;
int rc;
- if (validGlxDrawable(client, drawId, GLX_DRAWABLE_ANY,
- DixWriteAccess, &pGlxDraw, &rc)) {
+ rc = dixLookupResourceByType((void **)&pGlxDraw, drawId,
+ __glXDrawableRes, client, DixWriteAccess);
+ if (rc == Success &&
+ /* If pGlxDraw->drawId == drawId, drawId is a valid GLX drawable.
+ * Otherwise, if pGlxDraw->type == GLX_DRAWABLE_WINDOW, drawId is
+ * an X window, but the client has already created a GLXWindow
+ * associated with it, so we don't want to create another one. */
+ (pGlxDraw->drawId == drawId ||
+ pGlxDraw->type == GLX_DRAWABLE_WINDOW)) {
if (glxc != NULL &&
glxc->config != NULL &&
glxc->config != pGlxDraw->config) {
--
2.31.1