CVE-2025-40110

In the Linux kernel, the following vulnerability has been resolved:

drm/vmwgfx: Fix a null-ptr access in the cursor snooper

Check that the resource which is converted to a surface exists before

trying to use the cursor snooper on it.

vmw_cmd_res_check allows explicit invalid (SVGA3D_INVALID_ID) identifiers

because some svga commands accept SVGA3D_INVALID_ID to mean "no surface",

unfortunately functions that accept the actual surfaces as objects might

(and in case of the cursor snooper, do not) be able to handle null

objects. Make sure that we validate not only the identifier (via the

vmw_cmd_res_check) but also check that the actual resource exists before

trying to do something with it.

Fixes unchecked null-ptr reference in the snooping code.