[PATCH 0/5] fscrypt, fs-verity: one-time init fixes

[Eric Biggers <ebiggers@kernel.org>]

This series fixes up some cases in fs/crypto/ and fs/verity/ where
"one-time init" is implemented using READ_ONCE() instead of
smp_load_acquire() but it's not obviously correct.

One case is fixed by using a better approach that removes the need to
initialize anything.  The others are fixed by upgrading READ_ONCE() to
smp_load_acquire().  I've also improved the comments.

This is motivated by the discussions at 
https://lkml.kernel.org/linux-fsdevel/20200713033330.205104-1-ebiggers@kernel.org/T/#u
and
https://lkml.kernel.org/linux-fsdevel/20200717044427.68747-1-ebiggers@kernel.org/T/#u

These fixes are improvements over the status quo, so I'd prefer to apply
them now, without waiting for any potential new generic one-time-init
macros (which based on the latest discussion, won't be flexible enough
to handle most of these cases anyway).

Eric Biggers (5):
  fscrypt: switch fscrypt_do_sha256() to use the SHA-256 library
  fscrypt: use smp_load_acquire() for fscrypt_prepared_key
  fscrypt: use smp_load_acquire() for ->s_master_keys
  fscrypt: use smp_load_acquire() for ->i_crypt_info
  fs-verity: use smp_load_acquire() for ->i_verity_info

 fs/crypto/Kconfig           |  2 +-
 fs/crypto/fname.c           | 41 +++++++++----------------------------
 fs/crypto/fscrypt_private.h | 15 ++++++++------
 fs/crypto/inline_crypt.c    |  6 ++++--
 fs/crypto/keyring.c         | 15 +++++++++++---
 fs/crypto/keysetup.c        | 18 +++++++++++++---
 fs/crypto/policy.c          |  4 ++--
 fs/verity/open.c            | 15 +++++++++++---
 include/linux/fscrypt.h     | 29 +++++++++++++++++++++-----
 include/linux/fsverity.h    |  9 ++++++--
 10 files changed, 96 insertions(+), 58 deletions(-)

-- 
2.27.0