[S] Change in coreboot[main]: drivers/efi/capsules.c: check for overflows

[Sergii Dmytruk (Code Review)]

Sergii Dmytruk has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/84541?usp=email )

Change subject: drivers/efi/capsules.c: check for overflows
......................................................................

drivers/efi/capsules.c: check for overflows

Change-Id: I43d17d77197fc2cbd721d47941101551603c352a
Signed-off-by: Sergii Dmytruk 
---
M src/drivers/efi/capsules.c
1 file changed, 20 insertions(+), 1 deletion(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/41/84541/1

diff --git a/src/drivers/efi/capsules.c b/src/drivers/efi/capsules.c
index e674e33..cf15c3c 100644
--- a/src/drivers/efi/capsules.c
+++ b/src/drivers/efi/capsules.c
@@ -344,7 +344,20 @@
    		goto error;
    	}

-		data_size += ALIGN_UP(capsule_hdr->CapsuleImageSize, CAPSULE_ALIGNMENT);
+		uint32_t capsule_size =
+			ALIGN_UP(capsule_hdr->CapsuleImageSize, CAPSULE_ALIGNMENT);
+		if (capsule_size == 0) {
+			printk(BIOS_ERR, "capsules: capsule's size is too large (%#x).\n",
+			       capsule_hdr->CapsuleImageSize);
+			goto error;
+		}
+		if (data_size + capsule_size < data_size) {
+			printk(BIOS_ERR,
+			       "capsules: capsules' size is too large (%#llx + %#x).\n",
+			       data_size, capsule_size);
+			goto error;
+		}
+		data_size += capsule_size;

uint32_t size_left = capsule_hdr->CapsuleImageSize;
    	while (size_left != 0) {
@@ -384,6 +397,12 @@
    }

/* Increase the size only on successful parsing of the capsule block. */
+	if (*total_data_size + data_size < *total_data_size) {
+		printk(BIOS_ERR,
+		       "capsules: total capsule's size is too large (%#llx + %#llx).\n",
+		       *total_data_size, data_size);
+		goto error;
+	}
    *total_data_size += data_size;

return block;