drm/amd/pm: Validate pp_table header before reading size

smu_sys_set_pp_table() reads usStructureSize from the uploaded
pp_table buffer before validating that the buffer contains a complete
ATOM_COMMON_TABLE_HEADER. A short write can therefore make the driver
read past the supplied sysfs buffer.

Reject empty or header-short uploads before dereferencing the header
pointer.
Keep the existing structure-size check for the full uploaded table.

Signed-off-by: Yang Wang <kevinyang.wang@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

0 files changed, 0 insertions, 0 deletions