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Date:      Wed, 19 Jun 1996 04:13:32 -0700 (PDT)
From:      "Jordan K. Hubbard" <jkh@time.cdrom.com>
To:        FreeBSD-gnats-submit@freebsd.org
Subject:   kern/1336: Permission for .. in NFS mounts is somewhat non-intuitive
Message-ID:  <199606191113.EAA29196@time.cdrom.com>
Resent-Message-ID: <199606191120.EAA07808@freefall.freebsd.org>

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>Number:         1336
>Category:       kern
>Synopsis:       Permission for .. in NFS mounts is somewhat non-intuitive
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Wed Jun 19 04:20:01 PDT 1996
>Last-Modified:
>Originator:     Jordan K. Hubbard
>Organization:
- Jordan Hubbard
  FreeBSD Project
>Release:        FreeBSD 2.2-CURRENT i386
>Environment:

Two machines, client and server.  The following permissions for /u exist
on each:

client-> ls -lgd /u
drwxr-x---  2 root  wheel  512 Jun 19 04:02 /u

server-> ls -lgd /u
drwxr-xr-x  2 root  wheel  512 Jun 19 04:02 /u

The following NFS mount has also been done:

	client-> mount server:/u /u

>Description:

	If an ordinary user (e.g. not root and not in group wheel) on
	the client attempts to do a pwd(1) in /u, the operation will
	fail.  This appears to be due to the fact that pwd walks up
	the directory hierarchy by opening ".." and the permissions
	of the mount mount rather than the mounted directory are checked.

	If nothing else, this violates the principle of least surprise and
	can be a very non-obvious problem for the user given that the mount
	point permissions are obscured.

>How-To-Repeat:

	See above.
>Fix:
>Audit-Trail:
>Unformatted:



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