Find out how flame-proof my underwear really is.

bin/rm/rm.1

@@ -31,7 +31,7 @@
 .\"	@(#)rm.1	8.5 (Berkeley) 12/5/94
 .\" $FreeBSD$
 .\"
-.Dd January 28, 1999
+.Dd October 04, 2004
 .Dt RM 1
 .Os
 .Sh NAME
@@ -111,6 +111,7 @@ The
 utility removes symbolic links, not the files referenced by the links.
 .Pp
 It is an error to attempt to remove the files
+.Dq / ,
 .Dq .\&
 or
 .Dq .. .

bin/rm/rm.c

@@ -62,6 +62,7 @@ uid_t uid;
 
 int	check(char *, char *, struct stat *);
 void	checkdot(char **);
+void	checkslash(char **);
 void	rm_file(char **);
 int	rm_overwrite(char *, struct stat *);
 void	rm_tree(char **);
@@ -140,6 +141,7 @@ main(int argc, char *argv[])
 	}
 
 	checkdot(argv);
+	checkslash(argv);
 	uid = geteuid();
 
 	if (*argv) {
@@ -465,6 +467,27 @@ check(char *path, char *name, struct stat *sp)
 	return (first == 'y' || first == 'Y');
 }
 
+#define ISSLASH(a)	((a)[0] == '/' && (a)[1] == '\0')
+void
+checkslash(char **argv)
+{
+	char **t, **u;
+	int complained;
+
+	complained = 0;
+	for (t = argv; *t;) {
+		if (ISSLASH(*t)) {
+			if (!complained++)
+				warnx("\"/\" may not be removed");
+			eval = 1;
+			for (u = t; u[0] != NULL; ++u)
+				u[0] = u[1];
+		} else {
+			++t;
+		}
+	}
+}
+
 #define ISDOT(a)	((a)[0] == '.' && (!(a)[1] || ((a)[1] == '.' && !(a)[2])))
 void
 checkdot(char **argv)