From: Milan Broz <gmazyland@gmail.com>
Date: Sat, 22 Nov 2014 08:36:04 +0000 (+0100)
Subject: dm crypt: use memzero_explicit for on-stack buffer
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=a6e37a9dcf822402ad1f9afc5a7bca0c98a486a1;p=karo-tx-linux.git

dm crypt: use memzero_explicit for on-stack buffer

commit 1a71d6ffe18c0d0f03fc8531949cc8ed41d702ee upstream.

Use memzero_explicit to cleanup sensitive data allocated on stack
to prevent the compiler from optimizing and removing memset() calls.

Signed-off-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 9533f835ce07..4a8d19d0a5a4 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -709,7 +709,7 @@ static int crypt_iv_tcw_whitening(struct crypt_config *cc,
 	for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++)
 		crypto_xor(data + i * 8, buf, 8);
 out:
-	memset(buf, 0, sizeof(buf));
+	memzero_explicit(buf, sizeof(buf));
 	return r;
 }