CVE-2026-72327: drm/v3d: Reject invalid indirect BO handle in indirect CSD setup

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

drm/v3d: Reject invalid indirect BO handle in indirect CSD setup

v3dgetcpuindirectcsdparams() looks up the indirect buffer object from a userspace-supplied handle but never checks the result. A bogus or stale handle makes drmgemobjectlookup() return NULL, which is then stored in info->indirect and only dereferenced later when the indirect CSD job runs, turning a userspace mistake into a NULL pointer dereference in the kernel.

Bail out with -ENOENT as soon as the lookup fails, so the bad handle is rejected at submission time.