[vdisk] Treat 8.3 filename as a single 11-byte array

Eliminate complaints from Coverity by explicitly declaring the 8.3 filename as an 11-byte array (rather than an 8-byte array followed by a 3-byte array). Signed-off-by: Michael Brown <mbrown@fensystems.co.uk>
ipxe · May 10, 2017 · bb21155 · bb21155
1 parent 7f42b27
commit bb21155
Show file tree

Hide file tree

Showing 2 changed files with 14 additions and 8 deletions.
diff --git a/src/vdisk.c b/src/vdisk.c
@@ -197,18 +197,16 @@ vdisk_directory_entry ( union vdisk_directory_entry *dirent, const char *name,
 	unsigned int i;
 
 	/* Populate directory entry (with invalid 8.3 filename) */
-	memset ( dos->dos.filename, ' ', sizeof ( dos->dos.filename ) );
-	memset ( dos->dos.extension, ' ', sizeof ( dos->dos.extension ) );
+	memset ( dos->dos.filename.raw, ' ', sizeof ( dos->dos.filename.raw ) );
 	dos->dos.attr = attr;
 	dos->dos.size = len;
 	dos->dos.cluster_high = ( cluster >> 16 );
 	dos->dos.cluster_low = ( cluster & 0xffff );
 
 	/* Calculate checksum of 8.3 filename */
 	checksum = 0;
-	checksum_data = ( ( uint8_t * ) dos->dos.filename );
-	for ( i = 0 ; i < ( sizeof ( dos->dos.filename ) +
-			    sizeof ( dos->dos.extension ) ) ; i++ ) {
+	checksum_data = dos->dos.filename.raw;
+	for ( i = 0 ; i < sizeof ( dos->dos.filename.raw ) ; i++ ) {
 		checksum = ( ( ( ( checksum & 1 ) << 7 ) |
 			       ( checksum >> 1 ) ) +
 			     *(checksum_data++) );

diff --git a/src/vdisk.h b/src/vdisk.h
@@ -361,9 +361,17 @@ struct vdisk_fsinfo {
 /** An 8.3 filename record */
 struct vdisk_short_filename {
 	/** Filename */
-	char filename[8];
-	/** Extension */
-	char extension[3];
+	union {
+		/** Structured 8.3 base name and extension */
+		struct {
+			/** Base name */
+			char base[8];
+			/** Extension */
+			char ext[3];
+		} __attribute__ (( packed ));
+		/** Raw bytes */
+		uint8_t raw[11];
+	} filename;
 	/** Attributes */
 	uint8_t attr;
 	/** Reserved */