bin/68165: df fails to check fs type with -t and inaccessible mount point

[Christian S.J. Peron]

Synopsis: df fails to check fs type with -t and inaccessible mount point

Responsible-Changed-From-To: freebsd-bugs->csjp
Responsible-Changed-By: csjp
Responsible-Changed-When: Sat Jun 26 07:56:05 GMT 2004
Responsible-Changed-Why: 
I will take this one.  This PR brings up a more interesting
problem, if the parent directory of a mount point does not
have execute-search permissions, should the user be able
to access any information about the mount point in the
first place, as the path to the mount-point itself exposes
a filename within a restricted directory.

http://www.freebsd.org/cgi/query-pr.cgi?pr=68165