From: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Date: Fri, 19 Oct 2018 23:01:52 +0000 (+0300)
Subject: crypto: cfb - fix decryption
X-Git-Tag: v4.19.14~49
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=99dcd45f274e10b0a4b04f2836218762ed2294d4;p=platform%2Fkernel%2Flinux-rpi.git

crypto: cfb - fix decryption

commit fa4600734b74f74d9169c3015946d4722f8bcf79 upstream.

crypto_cfb_decrypt_segment() incorrectly XOR'ed generated keystream with
IV, rather than with data stream, resulting in incorrect decryption.
Test vectors will be added in the next patch.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/crypto/cfb.c b/crypto/cfb.c
index 20987d0..e81e456 100644
--- a/crypto/cfb.c
+++ b/crypto/cfb.c
@@ -144,7 +144,7 @@ static int crypto_cfb_decrypt_segment(struct skcipher_walk *walk,
 
 	do {
 		crypto_cfb_encrypt_one(tfm, iv, dst);
-		crypto_xor(dst, iv, bsize);
+		crypto_xor(dst, src, bsize);
 		iv = src;
 
 		src += bsize;