tree ca8ef4015ad1e80325df02dcd4ecfe261e1a4f9f
parent 363383277081ce831642b72df40932ee05ce40a2
author Frank Filz <ffilzlnx@us.ibm.com> 1242682900 -0400
committer Linus Torvalds <torvalds@linux-foundation.org> 1242702672 -0700

nfs: Fix NFS v4 client handling of MAY_EXEC in nfs_permission.

The problem is that permission checking is skipped if atomic open is
possible, but when exec opens a file, it just opens it O_READONLY which
means EXEC permission will not be checked at that time.

This problem is observed by the following sequence (executed as root):

  mount -t nfs4 server:/ /mnt4
  echo "ls" >/mnt4/foo
  chmod 744 /mnt4/foo
  su guest -c "mnt4/foo"

Signed-off-by: Frank Filz <ffilzlnx@us.ibm.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
Tested-by: Eugene Teo <eugeneteo@kernel.sg>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>