autofs4: fix incorrect return from root.c:try_to_fill_dentry()
commit9d2de6ad2a78bb8b60bf7a54e6043dca44e9a801
authorJeff Moyer <jmoyer@redhat.com>
Thu, 1 May 2008 11:35:09 +0000 (1 04:35 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 1 May 2008 15:04:01 +0000 (1 08:04 -0700)
tree6e5b7aea51d739ba0e26e4d795d53093ded3933a
parent033790449ba9c4dcf8478a87693d33df625c23b5
autofs4: fix incorrect return from root.c:try_to_fill_dentry()

Jeff Moyer has identified a case where the autofs4 function
root.c:try_to_fill_dentry() can return -EBUSY when it should return 0.

Jeff's description of the way this happens is:

"automount starts an expire for directory d.  after the callout to the daemon,
but before the rmdir, another process tries to walk into the same directory.
It puts itself onto the waitq, pending the expiration.

When the expire finishes, the second process is woken up.  In
try_to_fill_dentry, it does this check:

                status = d_invalidate(dentry);
                if (status != -EBUSY)
                        return -EAGAIN;

And status is EBUSY.  The dentry still has a non-zero d_inode, and the
flags do not contain LOOKUP_CONTINUE or LOOKUP_DIRECTORY

So, we fall through and return -EBUSY to the caller."

Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/autofs4/root.c