ln -F

[slash@peereboom.us]

>Submitter-Id:	net
>Originator:	Marco Peereboom
>Organization:
net
>Confidential:	no
>Synopsis:	Removed undocumented -F option in ln.
>Severity:	serious
>Priority:	high
>Category:	user
>Class:		change-request
>Release:	
>Environment:
	System      : OpenBSD 3.1
	Architecture: OpenBSD.*
	Machine     : All
>Description:
	drauku@drauku.net found an undocumented feature in ln that is potentially dangerous.
	ln -F hard links directories this is dangerous during fsck (todd@) and may
	cause kernel lockups (art@). I verfied that the filesystem allows it.
>How-To-Repeat:

>Fix:
--- ln.c.old    Sun Jul 21 08:59:46 2002
+++ ln.c        Sun Jul 21 09:11:03 2002
@@ -58,7 +58,6 @@
 #include <string.h>
 #include <unistd.h>
 
-int    dirflag;                        /* Undocumented directory flag. */
 int    fflag;                          /* Unlink existing files. */
 int    hflag;                          /* Check new name for symlink first. */
 int    sflag;                          /* Symbolic, not hard, link. */
@@ -75,11 +74,8 @@
        int ch, exitval;
        char *sourcedir;
 
-       while ((ch = getopt(argc, argv, "Ffhns")) != -1)
+       while ((ch = getopt(argc, argv, "fhns")) != -1)
                switch (ch) {
-               case 'F':
-                       dirflag = 1;    /* XXX: deliberately undocumented. */
-                       break;
                case 'f':
                        fflag = 1;
                        break;
@@ -129,11 +125,6 @@
                /* If target doesn't exist, quit now. */
                if (stat(target, &sb)) {
                        warn("%s", target);
-                       return (1);
-               }
-               /* Only symbolic links to directories, unless -F option used. */
-               if (!dirflag && S_ISDIR(sb.st_mode)) {
-                       warnx("%s: is a directory", target);
                        return (1);
                }
        }