[PATCH] ramdac: Check sPriv != NULL in xf86CheckHWCursor()

[Alex Goins]

xf86CheckHWCursor() would dereference sPriv without NULL checking it. If Option
"SWCursor" is specified, sPriv == NULL. In this case we should assume that HW
cursors are not supported.

Signed-off-by: Alex Goins <agoins at nvidia.com>
Reviewed-by: Andy Ritger <aritger at nvidia.com>
---
 hw/xfree86/ramdac/xf86HWCurs.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/hw/xfree86/ramdac/xf86HWCurs.c b/hw/xfree86/ramdac/xf86HWCurs.c
index da2b181..5e99526 100644
--- a/hw/xfree86/ramdac/xf86HWCurs.c
+++ b/hw/xfree86/ramdac/xf86HWCurs.c
@@ -148,7 +148,8 @@ xf86CheckHWCursor(ScreenPtr pScreen, CursorPtr cursor, xf86CursorInfoPtr infoPtr
             continue;
 
         sPriv = dixLookupPrivate(&pSlave->devPrivates, xf86CursorScreenKey);
-        if (!xf86ScreenCheckHWCursor(pSlave, cursor, sPriv->CursorInfoPtr))
+        if (!sPriv ||
+            !xf86ScreenCheckHWCursor(pSlave, cursor, sPriv->CursorInfoPtr))
             return FALSE;
     }
     return TRUE;
-- 
1.9.1