When we SMB3 mounted with mapchars (to allow reserved characters : \ / > < * ?
via the Unicode Windows to POSIX remap range) empty paths
(eg when we open "" to query the root of the SMB3 directory on mount) were not
null terminated so we sent garbarge as a path name on empty paths which caused
SMB2/SMB2.1/SMB3 mounts to fail when mapchars was specified.  mapchars is
particularly important since Unix Extensions for SMB3 are not supported (yet)

Signed-off-by: Steve French <smfrench@gmail.com>
Cc: <stable@vger.kernel.org>
Reviewed-by: David Disseldorp <ddiss@suse.de>

Before satisfying a read with cache=loose, we should always check
that the pagecache is valid before allowing a read to be satisfied
out of it.

Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: Steve French <smfrench@gmail.com>

commit d81b8a40e2ece0a9ab57b1fe1798e291e75bf8fc
("CIFS: Cleanup cifs open codepath")
changed disposition to FILE_OPEN.

Signed-off-by: Björn Baumbach <bb@sernet.de>
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Stefan Metzmacher <metze@samba.org>
Cc: <stable@vger.kernel.org> # v3.14+
Cc: Pavel Shilovsky <piastry@etersoft.ru>
Cc: Steve French <sfrench@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>

Pull vfs updates from Al Viro:
 "This the bunch that sat in -next + lock_parent() fix.  This is the
  minimal set; there's more pending stuff.

  In particular, I really hope to get acct.c fixes merged this cycle -
  we need that to deal sanely with delayed-mntput stuff.  In the next
  pile, hopefully - that series is fairly short and localized
  (kernel/acct.c, fs/super.c and fs/namespace.c).  In this pile: more
  iov_iter work.  Most of prereqs for ->splice_write with sane locking
  order are there and Kent's dio rewrite would also fit nicely on top of
  this pile"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (70 commits)
  lock_parent: don't step on stale ->d_parent of all-but-freed one
  kill generic_file_splice_write()
  ceph: switch to iter_file_splice_write()
  shmem: switch to iter_file_splice_write()
  nfs: switch to iter_splice_write_file()
  fs/splice.c: remove unneeded exports
  ocfs2: switch to iter_file_splice_write()
  ->splice_write() via ->write_iter()
  bio_vec-backed iov_iter
  optimize copy_page_{to,from}_iter()
  bury generic_file_aio_{read,write}
  lustre: get rid of messing with iovecs
  ceph: switch to ->write_iter()
  ceph_sync_direct_write: stop poking into iov_iter guts
  ceph_sync_read: stop poking into iov_iter guts
  new helper: copy_page_from_iter()
  fuse: switch to ->write_iter()
  btrfs: switch to ->write_iter()
  ocfs2: switch to ->write_iter()
  xfs: switch to ->write_iter()
  ...

Backmerge of dcache.c changes from mainline.  It's that, or complete
rebase...

Conflicts:
	fs/splice.c

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Pull CIFS fixes from Steve French.

* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
  CIFS: Fix memory leaks in SMB2_open
  cifs: ensure that vol->username is not NULL before running strlen on it
  Clarify SMB2/SMB3 create context and add missing ones
  Do not send ClientGUID on SMB2.02 dialect
  cifs: Set client guid on per connection basis
  fs/cifs/netmisc.c: convert printk to pr_foo()
  fs/cifs/cifs.c: replace seq_printf by seq_puts
  Update cifs version number to 2.03
  fs: cifs: new helper: file_inode(file)
  cifs: fix potential races in cifs_revalidate_mapping
  cifs: new helper function: cifs_revalidate_mapping
  cifs: convert booleans in cifsInodeInfo to a flags field
  cifs: fix cifs_uniqueid_to_ino_t not to ever return 0

Cc: <stable@vger.kernel.org> # v3.12+
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Reviewed-by: Shirish Pargaonkar <spargaonkar@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>

Dan Carpenter says:

The patch 04febabcf55b: "cifs: sanitize username handling" from Jan
17, 2012, leads to the following static checker warning:

	fs/cifs/connect.c:2231 match_session()
	error: we previously assumed 'vol->username' could be null (see line 2228)

fs/cifs/connect.c
  2219                  /* NULL username means anonymous session */
  2220                  if (ses->user_name == NULL) {
  2221                          if (!vol->nullauth)
  2222                                  return 0;
  2223                          break;
  2224                  }
  2225
  2226                  /* anything else takes username/password */
  2227                  if (strncmp(ses->user_name,
  2228                              vol->username ? vol->username : "",
                                    ^^^^^^^^^^^^^
We added this check for vol->username here.

  2229                              CIFS_MAX_USERNAME_LEN))
  2230                          return 0;
  2231                  if (strlen(vol->username) != 0 &&
                                   ^^^^^^^^^^^^^
But this dereference is not checked.

  2232                      ses->password != NULL &&
  2233                      strncmp(ses->password,
  2234                              vol->password ? vol->password : "",
  2235                              CIFS_MAX_PASSWORD_LEN))
  2236                          return 0;

...fix this by ensuring that vol->username is not NULL before running
strlen on it.

Signed-off-by: Jeff Layton <jlayton@poochiereds.net>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steve French <smfrench@gmail.com>

Clarify comments for create contexts which we do send,
and fix typo in one create context definition and add
newer SMB3 create contexts to the list.

Signed-off-by: Steve French <smfrench@gmail.com>

ClientGUID must be zero for SMB2.02 dialect.  See section 2.2.3
of MS-SMB2. For SMB2.1 and later it must be non-zero.

Signed-off-by: Steve French <smfrench@gmail.com>
CC: Sachin Prabhu <sprabhu@redhat.com>