By using the same code for both MakeWindowOptional and CreateRootWindow,
we ensure that new WindowOptPtrs are always fully initialized.
Previously, CreateRootWindow did not initialize optional->cursor. It
relied on InitRootWindow to overwrite it later, which seems like a wild
pointer dereference just waiting to happen.
Signed-off-by: Jamey Sharp <ja...@minilop.net>
---
dix/window.c | 74 +++++++++++++++++++++++++++------------------------------
1 files changed, 35 insertions(+), 39 deletions(-)
diff --git a/dix/window.c b/dix/window.c
index 44bfa18..c87020d 100644
--- a/dix/window.c
+++ b/dix/window.c
@@ -152,6 +152,12 @@ static unsigned char _back_msb[4] = {0x11, 0x44, 0x22,
0x88};
static Bool WindowParentHasDeviceCursor(WindowPtr pWin,
DeviceIntPtr pDev,
CursorPtr pCurs);
+static WindowOptPtr
+AllocateWindowOptional(CursorPtr cursor,
+ VisualID visual,
+ Colormap colormap,
+ Mask dontPropagateMask);
+
static Bool
WindowSeekDeviceCursor(WindowPtr pWin,
DeviceIntPtr pDev,
@@ -481,25 +487,11 @@ CreateRootWindow(ScreenPtr pScreen)
pWin->parent = NullWindow;
SetWindowToDefaults(pWin);
- pWin->optional = malloc(sizeof (WindowOptRec));
+ pWin->optional = AllocateWindowOptional(None,
+ pScreen->rootVisual, pScreen->defColormap, 0);
if (!pWin->optional)
return FALSE;
- pWin->optional->dontPropagateMask = 0;
- pWin->optional->otherEventMasks = 0;
- pWin->optional->otherClients = NULL;
- pWin->optional->passiveGrabs = NULL;
- pWin->optional->userProps = NULL;
- pWin->optional->backingBitPlanes = ~0L;
- pWin->optional->backingPixel = 0;
- pWin->optional->boundingShape = NULL;
- pWin->optional->clipShape = NULL;
- pWin->optional->inputShape = NULL;
- pWin->optional->inputMasks = NULL;
- pWin->optional->deviceCursors = NULL;
- pWin->optional->colormap = pScreen->defColormap;
- pWin->optional->visual = pScreen->rootVisual;
-
pWin->nextSib = NullWindow;
pWin->drawable.id = FakeClientID(0);
@@ -3500,18 +3492,21 @@ CheckWindowOptionalNeed (WindowPtr w)
* values.
*/
-Bool
-MakeWindowOptional (WindowPtr pWin)
+static WindowOptPtr
+AllocateWindowOptional (CursorPtr cursor,
+ VisualID visual,
+ Colormap colormap,
+ Mask dontPropagateMask)
{
- WindowOptPtr optional;
- WindowOptPtr parentOptional;
-
- if (pWin->optional)
- return TRUE;
- optional = malloc(sizeof (WindowOptRec));
+ WindowOptPtr optional = malloc(sizeof (WindowOptRec));
if (!optional)
- return FALSE;
- optional->dontPropagateMask = DontPropagateMasks[pWin->dontPropagate];
+ return NULL;
+ optional->cursor = cursor;
+ if (cursor)
+ cursor->refcnt++;
+ optional->visual = visual;
+ optional->colormap = colormap;
+ optional->dontPropagateMask = dontPropagateMask;
optional->otherEventMasks = 0;
optional->otherClients = NULL;
optional->passiveGrabs = NULL;
@@ -3523,21 +3518,22 @@ MakeWindowOptional (WindowPtr pWin)
optional->inputShape = NULL;
optional->inputMasks = NULL;
optional->deviceCursors = NULL;
+ return optional;
+}
+Bool
+MakeWindowOptional (WindowPtr pWin)
+{
+ WindowOptPtr parentOptional;
+
+ if (pWin->optional)
+ return TRUE;
parentOptional = FindWindowWithOptional(pWin)->optional;
- optional->visual = parentOptional->visual;
- if (!pWin->cursorIsNone)
- {
- optional->cursor = parentOptional->cursor;
- optional->cursor->refcnt++;
- }
- else
- {
- optional->cursor = None;
- }
- optional->colormap = parentOptional->colormap;
- pWin->optional = optional;
- return TRUE;
+ pWin->optional = AllocateWindowOptional(
+ pWin->cursorIsNone ? None : parentOptional->cursor,
+ parentOptional->visual, parentOptional->colormap,
+ DontPropagateMasks[pWin->dontPropagate]);
+ return pWin->optional != NULL;
}
/*
--
1.7.5.4
_______________________________________________
xorg-devel@lists.x.org: X.Org development
Archives: http://lists.x.org/archives/xorg-devel
Info: http://lists.x.org/mailman/listinfo/xorg-devel
