[PATCH v5 00/13] Unseeded In-Kernel Randomness Fixes

[Jason A. Donenfeld]

It looks like critique of this has come to an end. Could somebody take
this into their tree for 4.12?

As discussed in [1], there is a problem with get_random_bytes being
used before the RNG has actually been seeded. The solution for fixing
this appears to be multi-pronged. One of those prongs involves adding
a simple blocking API so that modules that use the RNG in process
context can just sleep (in an interruptable manner) until the RNG is
ready to be used. This winds up being a very useful API that covers
a few use cases, several of which are included in this patch set.

[1] http://www.openwall.com/lists/kernel-hardening/2017/06/02/2

Changes v4->v5:
  - Old versions of gcc warned on an uninitialized variable, so set
    this to silence warning.

Jason A. Donenfeld (13):
  random: invalidate batched entropy after crng init
  random: add synchronous API for the urandom pool
  random: add get_random_{bytes,u32,u64,int,long,once}_wait family
  security/keys: ensure RNG is seeded before use
  crypto/rng: ensure that the RNG is ready before using
  iscsi: ensure RNG is seeded before use
  ceph: ensure RNG is seeded before using
  cifs: use get_random_u32 for 32-bit lock random
  rhashtable: use get_random_u32 for hash_rnd
  net/neighbor: use get_random_u32 for 32-bit hash random
  net/route: use get_random_int for random counter
  bluetooth/smp: ensure RNG is properly seeded before ECDH use
  random: warn when kernel uses unseeded randomness

 crypto/rng.c                              |  6 +-
 drivers/char/random.c                     | 93 +++++++++++++++++++++++++++----
 drivers/target/iscsi/iscsi_target_auth.c  | 14 ++++-
 drivers/target/iscsi/iscsi_target_login.c | 22 +++++---
 fs/cifs/cifsfs.c                          |  2 +-
 include/linux/net.h                       |  2 +
 include/linux/once.h                      |  2 +
 include/linux/random.h                    | 26 +++++++++
 lib/Kconfig.debug                         | 16 ++++++
 lib/rhashtable.c                          |  2 +-
 net/bluetooth/hci_request.c               |  6 ++
 net/bluetooth/smp.c                       | 18 ++++--
 net/ceph/ceph_common.c                    |  6 +-
 net/core/neighbour.c                      |  3 +-
 net/ipv4/route.c                          |  3 +-
 security/keys/encrypted-keys/encrypted.c  |  8 ++-
 security/keys/key.c                       | 16 +++---
 17 files changed, 198 insertions(+), 47 deletions(-)

-- 
2.13.0