From: Eric Biggers <ebiggers@google.com>
Date: Fri, 1 Feb 2019 07:51:37 +0000 (-0800)
Subject: crypto: morus - fix handling chunked inputs
X-Git-Tag: v4.19.31~153
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=c0bfdac6a4718f2973bea8ef9e0233fbf62440be;p=platform%2Fkernel%2Flinux-rpi.git

crypto: morus - fix handling chunked inputs

commit d644f1c8746ed24f81075480f9e9cb3777ae8d65 upstream.

The generic MORUS implementations all fail the improved AEAD tests
because they produce the wrong result with some data layouts.  The issue
is that they assume that if the skcipher_walk API gives 'nbytes' not
aligned to the walksize (a.k.a. walk.stride), then it is the end of the
data.  In fact, this can happen before the end.  Fix them.

Fixes: 396be41f16fd ("crypto: morus - Add generic MORUS AEAD implementations")
Cc: <stable@vger.kernel.org> # v4.18+
Cc: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/crypto/morus1280.c b/crypto/morus1280.c
index 3889c18..b83576b 100644
--- a/crypto/morus1280.c
+++ b/crypto/morus1280.c
@@ -366,18 +366,19 @@ static void crypto_morus1280_process_crypt(struct morus1280_state *state,
 					   const struct morus1280_ops *ops)
 {
 	struct skcipher_walk walk;
-	u8 *dst;
-	const u8 *src;
 
 	ops->skcipher_walk_init(&walk, req, false);
 
 	while (walk.nbytes) {
-		src = walk.src.virt.addr;
-		dst = walk.dst.virt.addr;
+		unsigned int nbytes = walk.nbytes;
 
-		ops->crypt_chunk(state, dst, src, walk.nbytes);
+		if (nbytes < walk.total)
+			nbytes = round_down(nbytes, walk.stride);
 
-		skcipher_walk_done(&walk, 0);
+		ops->crypt_chunk(state, walk.dst.virt.addr, walk.src.virt.addr,
+				 nbytes);
+
+		skcipher_walk_done(&walk, walk.nbytes - nbytes);
 	}
 }
 
diff --git a/crypto/morus640.c b/crypto/morus640.c
index da06ec2..b6a4774 100644
--- a/crypto/morus640.c
+++ b/crypto/morus640.c
@@ -365,18 +365,19 @@ static void crypto_morus640_process_crypt(struct morus640_state *state,
 					  const struct morus640_ops *ops)
 {
 	struct skcipher_walk walk;
-	u8 *dst;
-	const u8 *src;
 
 	ops->skcipher_walk_init(&walk, req, false);
 
 	while (walk.nbytes) {
-		src = walk.src.virt.addr;
-		dst = walk.dst.virt.addr;
+		unsigned int nbytes = walk.nbytes;
 
-		ops->crypt_chunk(state, dst, src, walk.nbytes);
+		if (nbytes < walk.total)
+			nbytes = round_down(nbytes, walk.stride);
 
-		skcipher_walk_done(&walk, 0);
+		ops->crypt_chunk(state, walk.dst.virt.addr, walk.src.virt.addr,
+				 nbytes);
+
+		skcipher_walk_done(&walk, walk.nbytes - nbytes);
 	}
 }