MFC: Fix a potential buffer overflow in the command line argument par…

…sing

	with 'ed [MAXPATHLEN + 1 chars]'. {from revision 1.15}

bin/ed/main.c

@@ -172,7 +172,9 @@ main(argc, argv)
 			if (read_file(*argv, 0) < 0 && !isatty(0))
 				quit(2);
 			else if (**argv != '!')
-				strcpy(old_filename, *argv);
+				if (strlcpy(old_filename, *argv, sizeof(old_filename))
+				    >= sizeof(old_filename))
+					quit(2);
 		} else if (argc) {
 			fputs("?\n", stderr);
 			if (**argv == '\0')
@@ -1342,8 +1344,8 @@ strip_escapes(s)
 	int i = 0;
 
 	REALLOC(file, filesz, MAXPATHLEN + 1, NULL);
-	/* assert: no trailing escape */
-	while ((file[i++] = (*s == '\\') ? *++s : *s))
+	while (i < filesz - 1	/* Worry about a possible trailing escape */
+	       && (file[i++] = (*s == '\\') ? *++s : *s))
 		s++;
 	return file;
 }