Pull vfs updates from Al Viro:

 - Preparations of parallel lookups (the remaining main obstacle is the
   need to move security_d_instantiate(); once that becomes safe, the
   rest will be a matter of rather short series local to fs/*.c

 - preadv2/pwritev2 series from Christoph

 - assorted fixes

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (32 commits)
  splice: handle zero nr_pages in splice_to_pipe()
  vfs: show_vfsstat: do not ignore errors from show_devname method
  dcache.c: new helper: __d_add()
  don't bother with __d_instantiate(dentry, NULL)
  untangle fsnotify_d_instantiate() a bit
  uninline d_add()
  replace d_add_unique() with saner primitive
  quota: use lookup_one_len_unlocked()
  cifs_get_root(): use lookup_one_len_unlocked()
  nfs_lookup: don't bother with d_instantiate(dentry, NULL)
  kill dentry_unhash()
  ceph_fill_trace(): don't bother with d_instantiate(dn, NULL)
  autofs4: don't bother with d_instantiate(dentry, NULL) in ->lookup()
  configfs: move d_rehash() into configfs_create() for regular files
  ceph: don't bother with d_rehash() in splice_dentry()
  namei: teach lookup_slow() to skip revalidate
  namei: massage lookup_slow() to be usable by lookup_one_len_unlocked()
  lookup_one_len_unlocked(): use lookup_dcache()
  namei: simplify invalidation logics in lookup_dcache()
  namei: change calling conventions for lookup_{fast,slow} and follow_managed()
  ...

the last time it was getting something other than NULL as
crypt_stat had been back in 2009...

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

This patch replaces uses of ablkcipher and blkcipher with skcipher,
and the long obsolete hash interface with shash.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Merge the type-specific data with the payload data into one four-word chunk
as it seems pointless to keep them separate.

Use user_key_payload() for accessing the payloads of overloaded
user-defined keys.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: linux-cifs@vger.kernel.org
cc: ecryptfs@vger.kernel.org
cc: linux-ext4@vger.kernel.org
cc: linux-f2fs-devel@lists.sourceforge.net
cc: linux-nfs@vger.kernel.org
cc: ceph-devel@vger.kernel.org
cc: linux-ima-devel@lists.sourceforge.net

The patch 237fead61998: "[PATCH] ecryptfs: fs/Makefile and
fs/Kconfig" from Oct 4, 2006, leads to the following static checker
warning:

  fs/ecryptfs/crypto.c:846 ecryptfs_new_file_context()
  error: off-by-one overflow 'crypt_stat->cipher' size 32.  rl = '0-32'

There is a mismatch between the size of ecryptfs_crypt_stat.cipher
and ecryptfs_mount_crypt_stat.global_default_cipher_name causing the
copy of the cipher name to cause a off-by-one string copy error. This
fix ensures the space reserved for this string is the same size including
the trailing zero at the end throughout ecryptfs.

This fix avoids increasing the size of ecryptfs_crypt_stat.cipher
and also ecryptfs_parse_tag_70_packet_silly_stack.cipher_string and instead
reduces the of ECRYPTFS_MAX_CIPHER_NAME_SIZE to 31 and includes the + 1 for
the end of string terminator.

NOTE: An overflow is not possible in practice since the value copied
into global_default_cipher_name is validated by
ecryptfs_code_for_cipher_string() at mount time. None of the allowed
cipher strings are long enough to cause the potential buffer overflow
fixed by this patch.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
[tyhicks: Added the NOTE about the overflow not being triggerable]
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>

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

If the underlying dentry doesn't have ->d_revalidate(), there's no need to
force dropping out of RCU mode.  All we need for that is to make freeing
ecryptfs_dentry_info RCU-delayed.

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

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

Make the switch from the blkcipher kernel crypto interface to the
ablkcipher interface.

encrypt_scatterlist() and decrypt_scatterlist() now use the ablkcipher
interface but, from the eCryptfs standpoint, still treat the crypto
operation as a synchronous operation. They submit the async request and
then wait until the operation is finished before they return. Most of
the changes are contained inside those two functions.

Despite waiting for the completion of the crypto operation, the
ablkcipher interface provides performance increases in most cases when
used on AES-NI capable hardware.

Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: Colin King <colin.king@canonical.com>
Reviewed-by: Zeev Zilberman <zeev@annapurnaLabs.com>
Cc: Dustin Kirkland <dustin.kirkland@gazzang.com>
Cc: Tim Chen <tim.c.chen@intel.com>
Cc: Ying Huang <ying.huang@intel.com>
Cc: Thieu Le <thieule@google.com>
Cc: Li Wang <dragonylffly@163.com>
Cc: Jarkko Sakkinen <jarkko.sakkinen@iki.fi>

Pull ecryptfs fixes from Tyler Hicks:
 "Minor code cleanups and new Kconfig option to disable /dev/ecryptfs

  The code cleanups fix up W=1 compiler warnings and some unnecessary
  checks.  The new Kconfig option, defaulting to N, allows the rarely
  used eCryptfs kernel to userspace communication channel to be compiled
  out.  This may be the first step in it being eventually removed."

Hmm.  I'm not sure whether these should be called "fixes", and it
probably should have gone in the merge window.  But I'll let it slide.

* tag 'ecryptfs-3.9-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs:
  eCryptfs: allow userspace messaging to be disabled
  eCryptfs: Fix redundant error check on ecryptfs_find_daemon_by_euid()
  ecryptfs: ecryptfs_msg_ctx_alloc_to_free(): remove kfree() redundant null check
  eCryptfs: decrypt_pki_encrypted_session_key(): remove kfree() redundant null check
  eCryptfs: remove unneeded checks in virt_to_scatterlist()
  eCryptfs: Fix -Wmissing-prototypes warnings
  eCryptfs: Fix -Wunused-but-set-variable warnings
  eCryptfs: initialize payload_len in keystore.c