cifs_get_root shouldn't use path with tree name
authorSachin Prabhu <sprabhu@redhat.com>
Thu, 15 Dec 2016 07:01:19 +0000 (12:31 +0530)
committerSteve French <smfrench@gmail.com>
Thu, 15 Dec 2016 07:42:54 +0000 (01:42 -0600)
commit374402a2a1dfbbee8ab1a5a32ec4887bf8c15d52
treee886fc71908f5e2ac4c97b68e30e7b364417cfb2
parent395664439c4945e4827543e3ca80f7b74e1bf733
cifs_get_root shouldn't use path with tree name

When a server returns the optional flag SMB_SHARE_IS_IN_DFS in response
to a tree connect, cifs_build_path_to_root() will return a pathname
which includes the hostname. This causes problems with cifs_get_root()
which separates each component and does a lookup for each component of
the path which in this case will incorrectly include looking up the
hostname component as a path component.

We encountered a problem with dfs shares hosted by a Netapp. When
connecting to nodes pointed to by the DFS share. The tree connect for
these nodes return SMB_SHARE_IS_IN_DFS resulting failures in lookup
in cifs_get_root().

RH bz: 1373153
The patch was tested against a Netapp simulator and by a user using an
actual Netapp server.

Signed-off-by: Sachin Prabhu <sprabhu@redhat.com>
Reported-by: Pierguido Lambri <plambri@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
fs/cifs/cifsfs.c
fs/cifs/cifsproto.h
fs/cifs/connect.c
fs/cifs/dir.c