@@ -43,7 +43,9 @@

 #include "scanners.h"

 #include "matcher.h"

-#define BLOCKSIZE 512

+#define TARHEADERSIZE 512

+/* BLOCKSIZE must be >= TARHEADERSIZE */

+#define BLOCKSIZE TARHEADERSIZE

 #define TARSIZEOFFSET 124

 #define TARSIZELEN 12

 #define TARCHECKSUMOFFSET 148

@@ -182,8 +184,9 @@ cli_untar(const char *dir, unsigned int posix, cli_ctx *ctx)

 			if((ret=cli_checklimits("cli_untar", ctx, 0, 0, 0))!=CL_CLEAN)

 				return ret;

-                        if (nread < TARCHECKSUMOFFSET + TARCHECKSUMLEN)

-                            return ret;

+			if (nread < TARHEADERSIZE) {

+				return CL_CLEAN;

+			}

 			checksum = getchecksum(block);

 			cli_dbgmsg("cli_untar: Candidate checksum = %d, [%o in octal]\n", checksum, checksum);

@@ -200,7 +203,6 @@ cli_untar(const char *dir, unsigned int posix, cli_ctx *ctx)

 				cli_dbgmsg("cli_untar: Checksum %d is valid.\n", checksum);

 			}

-			/* Notice assumption that BLOCKSIZE > 262 */

 			if(posix) {

 				strncpy(magic, block+257, 5);

 				magic[5] = '\0';