[coreboot-gerrit] Change in coreboot[master]: drivers/intel/fsp2_0: Allocate cfg_region_size for UPD

[Patrick Georgi (Code Review)]

Patrick Georgi has submitted this change. ( https://review.coreboot.org/c/coreboot/+/35349 )

Change subject: drivers/intel/fsp2_0: Allocate cfg_region_size for UPD
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drivers/intel/fsp2_0: Allocate cfg_region_size for UPD

In FSP-S, the driver constructs its pointer to UPD using the offset
in the header.  Similarly, use the header's cfg_region_size for
allocating memory and copying the default configuration.

Add sanity checks for unexpedted configuration and UPD header
conditions.

TEST=Verify OK on Mandolin, verify a mock error condition
BUG=b:140648081

Change-Id: I20fad0e27a2ad537898b6d01e5241e1508da690c
Signed-off-by: Marshall Dawson 
Reviewed-on: https://review.coreboot.org/c/coreboot/+/35349
Tested-by: build bot (Jenkins) 
Reviewed-by: Aaron Durbin 
Reviewed-by: Furquan Shaikh 
---
M src/drivers/intel/fsp2_0/silicon_init.c
1 file changed, 10 insertions(+), 2 deletions(-)

Approvals:
  build bot (Jenkins): Verified
  Aaron Durbin: Looks good to me, approved
  Furquan Shaikh: Looks good to me, approved

diff --git a/src/drivers/intel/fsp2_0/silicon_init.c b/src/drivers/intel/fsp2_0/silicon_init.c
index e72e4ac..ecc6e96 100644
--- a/src/drivers/intel/fsp2_0/silicon_init.c
+++ b/src/drivers/intel/fsp2_0/silicon_init.c
@@ -39,9 +39,17 @@
    	die_with_post_code(POST_INVALID_VENDOR_BINARY,
    		"Invalid FSPS signature\n");

-	upd = xmalloc(sizeof(FSPS_UPD));
+	/* Disallow invalid config regions.  Default settings are likely bad
+	 * choices for coreboot, and different sized UPD from what the region
+	 * allows is potentially a build problem.
+	 */
+	if (!hdr->cfg_region_size || hdr->cfg_region_size != sizeof(FSPS_UPD))
+		die_with_post_code(POST_INVALID_VENDOR_BINARY,
+			"Invalid FSPS UPD region\n");

-	memcpy(upd, supd, sizeof(FSPS_UPD));
+	upd = xmalloc(hdr->cfg_region_size);
+
+	memcpy(upd, supd, hdr->cfg_region_size);

/* Give SoC/mainboard a chance to populate entries */
    platform_fsp_silicon_init_params_cb(upd);