avoid off-by-one error in run_upload_archive

Make sure that buf has enough space to store the trailing \0 of
the command line argument, too.

Signed-off-by: Jochen Voss <voss@seehuhn.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin-upload-archive.c

@@ -30,7 +30,7 @@ static int run_upload_archive(int argc, const char **argv, const char *prefix)
 	if (argc != 2)
 		usage(upload_archive_usage);
 
-	if (strlen(argv[1]) > sizeof(buf))
+	if (strlen(argv[1]) + 1 > sizeof(buf))
 		die("insanely long repository name");
 
 	strcpy(buf, argv[1]); /* enter-repo smudges its argument */