diff --git a/stand/libsa/cd9660.c b/stand/libsa/cd9660.c
index aa87466dc591..c339678d96fe 100644
--- a/stand/libsa/cd9660.c
+++ b/stand/libsa/cd9660.c
@@ -286,7 +286,7 @@ cd9660_open(const char *path, struct open_file *f)
 	struct file *fp = NULL;
 	void *buf;
 	struct iso_primary_descriptor *vd;
-	size_t buf_size, read, dsize, off;
+	size_t read, dsize, off;
 	daddr_t bno, boff;
 	struct iso_directory_record rec;
 	struct iso_directory_record *dp = NULL;
@@ -294,7 +294,8 @@ cd9660_open(const char *path, struct open_file *f)
 	bool isdir = false;
 
 	/* First find the volume descriptor */
-	buf = malloc(buf_size = ISO_DEFAULT_BLOCK_SIZE);
+	buf = malloc(MAX(ISO_DEFAULT_BLOCK_SIZE,
+	    sizeof(struct iso_primary_descriptor)));
 	vd = buf;
 	for (bno = 16;; bno++) {
 		twiddle(1);
@@ -438,8 +439,7 @@ cd9660_open(const char *path, struct open_file *f)
 	return 0;
 
 out:
-	if (fp)
-		free(fp);
+	free(fp);
 	free(buf);
 
 	return rc;
diff --git a/stand/libsa/cd9660read.c b/stand/libsa/cd9660read.c
index 7ad2e9c6d559..3f4e667f6942 100644
--- a/stand/libsa/cd9660read.c
+++ b/stand/libsa/cd9660read.c
@@ -35,6 +35,7 @@
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
+#include <sys/param.h>
 #include <fs/cd9660/iso.h>
 #include <fs/cd9660/cd9660_rrip.h>
 
@@ -220,7 +221,8 @@ dirmatch(const char *path, struct iso_directory_record *dp, int use_rrip,
 static uint64_t
 cd9660_lookup(const char *path)
 {
-	static char blkbuf[ISO_DEFAULT_BLOCK_SIZE];
+	static char blkbuf[MAX(ISO_DEFAULT_BLOCK_SIZE,
+	    sizeof(struct iso_primary_descriptor))];
 	struct iso_primary_descriptor *vd;
 	struct iso_directory_record rec;
 	struct iso_directory_record *dp = NULL;