tools: kwbimage: Verify size of v0 image header

Check that extended image header size is not larger than file size.

Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Stefan Roese <sr@denx.de>

diff --git a/tools/kwbimage.c b/tools/kwbimage.c
index 542779e..4709c6d 100644 (file)
--- a/tools/kwbimage.c
+++ b/tools/kwbimage.c
@@ -1670,6 +1670,9 @@ static int kwbimage_verify_header(unsigned char *ptr, int image_size,
                if (mhdr->ext & 0x1) {
                        struct ext_hdr_v0 *ext_hdr;
 
+                       if (header_size + sizeof(*ext_hdr) > image_size)
+                               return -FDT_ERR_BADSTRUCTURE;
+
                        ext_hdr = (struct ext_hdr_v0 *)
                                (ptr + sizeof(struct main_hdr_v0));
                        checksum = image_checksum8(ext_hdr,