[XS] Change in coreboot[main]: [NEEDS TEST] region: Check for overflows after offset calculation

[Nico Huber (Code Review)]

Nico Huber has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/79945?usp=email )

Change subject: [NEEDS TEST] region: Check for overflows after offset calculation
......................................................................

[NEEDS TEST] region: Check for overflows after offset calculation

As we currently do not know where overflows actually happen, this needs
testing to avoid boot failures due to potential bugs somewhere else.

Change-Id: Ia6054e6e9b6f13502351a2d94c8a0af15266e43e
Signed-off-by: Nico Huber 
---
M src/commonlib/region.c
1 file changed, 2 insertions(+), 1 deletion(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/45/79945/1

diff --git a/src/commonlib/region.c b/src/commonlib/region.c
index 4153f0a..9dc6637 100644
--- a/src/commonlib/region.c
+++ b/src/commonlib/region.c
@@ -22,7 +22,8 @@
 static int normalize_and_ok(const struct region *outer, struct region *inner)
 {
    inner->offset += region_offset(outer);
-	return region_is_subregion(outer, inner);
+	return region_end(inner) - 1 >= region_offset(inner) &&
+		region_is_subregion(outer, inner);
 }

static const struct region_device *rdev_root(const struct region_device *rdev)