drm/amdgpu: fix userq VA validation for sub-page buffers

amdgpu_userq_input_va_validate() converts expected_size to page count
with a plain right shift. For expected_size smaller than one GPU page,
the computed size becomes 0 and the range check is effectively bypassed.

This allows sub-page userq buffers (e.g. EOP/CSA) to pass validation
as long as the start VA is mapped, without verifying the full span.

Fix it by rejecting zero expected_size, checking overflow when
computing end address, and deriving page span from [start_addr,
end_addr] inclusive.

Signed-off-by: Candice Li <candice.li@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

0 files changed, 0 insertions, 0 deletions