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: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=1a71d6ffe18c0d0f03fc8531949cc8ed41d702ee;p=openwrt%2Fstaging%2Fblogic.git

dm crypt: use memzero_explicit for on-stack buffer

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>
Cc: stable@vger.kernel.org
---

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index cd15e0801228..ce11a90a33c3 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -711,7 +711,7 @@ 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;
 }