releases/3.14.28/dm-crypt-use-memzero_explicit-for-on-stack-buffer.patch

   1 From 1a71d6ffe18c0d0f03fc8531949cc8ed41d702ee Mon Sep 17 00:00:00 2001
   2 From: Milan Broz <gmazyland@gmail.com>
   3 Date: Sat, 22 Nov 2014 09:36:04 +0100
   4 Subject: dm crypt: use memzero_explicit for on-stack buffer
   5
   6 From: Milan Broz <gmazyland@gmail.com>
   7
   8 commit 1a71d6ffe18c0d0f03fc8531949cc8ed41d702ee upstream.
   9
  10 Use memzero_explicit to cleanup sensitive data allocated on stack
  11 to prevent the compiler from optimizing and removing memset() calls.
  12
  13 Signed-off-by: Milan Broz <gmazyland@gmail.com>
  14 Signed-off-by: Mike Snitzer <snitzer@redhat.com>
  15 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  16
  17 ---
  18  drivers/md/dm-crypt.c |    2 +-
  19  1 file changed, 1 insertion(+), 1 deletion(-)
  20
  21 --- a/drivers/md/dm-crypt.c
  22 +++ b/drivers/md/dm-crypt.c
  23 @@ -709,7 +709,7 @@ static int crypt_iv_tcw_whitening(struct
  24         for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++)
  25                 crypto_xor(data + i * 8, buf, 8);
  26  out:
  27 -       memset(buf, 0, sizeof(buf));
  28 +       memzero_explicit(buf, sizeof(buf));
  29         return r;
  30  }
  31