diff --git a/tools/firmware-utils/src/buffalo-tftp.c b/tools/firmware-utils/src/buffalo-tftp.c
index 1a2551a41c..087f9955b6 100644
--- a/tools/firmware-utils/src/buffalo-tftp.c
+++ b/tools/firmware-utils/src/buffalo-tftp.c
@@ -70,7 +70,6 @@ static int crypt_file(void)
 {
 	unsigned char *buf = NULL;
 	ssize_t src_len;
-	ssize_t crypt_len;
 	int err;
 	int ret = -1;
 
@@ -92,7 +91,6 @@ static int crypt_file(void)
 		goto out;
 	}
 
-	crypt_len = (src_len > 512) ? 512 : src_len;
 	if (do_decrypt)
 		crypt_header(buf, 512, crypt_key2, crypt_key1);
 	else
diff --git a/tools/firmware-utils/src/mkrtn56uimg.c b/tools/firmware-utils/src/mkrtn56uimg.c
index 973ab28d06..fe9ae2c877 100644
--- a/tools/firmware-utils/src/mkrtn56uimg.c
+++ b/tools/firmware-utils/src/mkrtn56uimg.c
@@ -89,13 +89,13 @@ calc_crc(image_header_t *hdr, void *data, uint32_t len)
 	/*
 	 * Calculate payload checksum
 	 */
-	hdr->ih_dcrc = htonl(crc32(0, data, len));
+	hdr->ih_dcrc = htonl(crc32(0, (Bytef *)data, len));
 	hdr->ih_size = htonl(len);
 	/*
 	 * Calculate header checksum
 	 */
 	hdr->ih_hcrc = 0;
-	hdr->ih_hcrc = htonl(crc32(0, hdr, sizeof(image_header_t)));
+	hdr->ih_hcrc = htonl(crc32(0, (Bytef *)hdr, sizeof(image_header_t)));
 }
 
 
@@ -166,7 +166,7 @@ process_image(char *progname, char *filename, op_mode_t opmode)
 	}
 
 	if (opmode == FACTORY) {
-		strncpy(&namebuf, (char *)&hdr->tail.ih_name, IH_NMLEN);
+		strncpy(namebuf, hdr->tail.ih_name, IH_NMLEN);
 		hdr->tail.asus.kernel.major = 0;
 		hdr->tail.asus.kernel.minor = 0;
 		hdr->tail.asus.fs.major = 0;
@@ -231,7 +231,7 @@ process_image(char *progname, char *filename, op_mode_t opmode)
 	if (opmode == FACTORY) {
 		hdr = ptr+offset_sec_header;
 		memcpy(hdr, ptr, sizeof(image_header_t));
-		strncpy((char *)&hdr->tail.ih_name, &namebuf, IH_NMLEN);
+		strncpy(hdr->tail.ih_name, namebuf, IH_NMLEN);
 		calc_crc(hdr, ptr+offset_kernel, offset_sqfs - offset_kernel);
 		calc_crc((image_header_t *)ptr, ptr+offset_kernel, offset_image_end - offset_kernel);
 	} else {