[PATCH 3/4] tools: kwbimage: Verify size of image data

Part of image data is 4 byte checksum, so every image must contain at least 4 bytes. Verify it to prevent memory corruptions.

Signed-off-by: Pali Rohár pali@kernel.org --- tools/kwbimage.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/kwbimage.c b/tools/kwbimage.c index 84c41210e39e..5ac34ac5e9c8 100644 --- a/tools/kwbimage.c +++ b/tools/kwbimage.c @@ -1757,7 +1757,7 @@ static int kwbimage_verify_header(unsigned char *ptr, int image_size, return -FDT_ERR_BADSTRUCTURE;

size = le32_to_cpu(mhdr->blocksize); - if (offset + size > image_size || size % 4 != 0) + if (size < 4 || offset + size > image_size || size % 4 != 0) return -FDT_ERR_BADSTRUCTURE;

if (image_checksum32(ptr + offset, size - 4) !=