firmware: coreboot: Validate table bounds

The existing coreboot_table_populate() bounds checks limit individual
entries to the mapped length.  However, coreboot_table_probe() replaces
the platform resource length with header and table sizes supplied by
firmware before mapping the full table.

A malformed table can overflow the 32-bit size addition or advertise an
extent beyond the resource, causing the driver to map and parse memory
outside the resource.  A resource shorter than the fixed header is also
mapped as though it contained a complete header.

Reject resources shorter than the fixed header.  After validating the
signature, require a complete header, calculate the advertised extent
with overflow checking, and reject extents beyond the resource before
remapping the table.

Fixes: d384d6f43d1e ("firmware: google memconsole: Add coreboot support")
Signed-off-by: Laxman Acharya Padhya <acharyalaxman8848@gmail.com>
Link: https://lore.kernel.org/r/20260801165651.42172-1-acharyalaxman8848@gmail.com
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>

0 files changed, 0 insertions, 0 deletions