linux-kernel - [PATCH 3/6] crypto: ccp - Check for caller result area before using it

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20140106193411.26918.88765.stgit@tlendack-t1.amdoffice.net>
Date:	Mon, 6 Jan 2014 13:34:11 -0600
From:	Tom Lendacky <thomas.lendacky@....com>
To:	<linux-crypto@...r.kernel.org>, <herbert@...dor.apana.org.au>,
	<davem@...emloft.net>
CC:	<linux-kernel@...r.kernel.org>
Subject: [PATCH 3/6] crypto: ccp - Check for caller result area before using it

For a hash operation, the caller doesn't have to supply a result
area on every call so don't use it / update it if it hasn't
been supplied.

Signed-off-by: Tom Lendacky <thomas.lendacky@....com>
---
 drivers/crypto/ccp/ccp-crypto-aes-cmac.c |    4 +++-
 drivers/crypto/ccp/ccp-crypto-sha.c      |    7 +++++--
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/crypto/ccp/ccp-crypto-aes-cmac.c b/drivers/crypto/ccp/ccp-crypto-aes-cmac.c
index 646c8d1..c6b8f9e 100644
--- a/drivers/crypto/ccp/ccp-crypto-aes-cmac.c
+++ b/drivers/crypto/ccp/ccp-crypto-aes-cmac.c
@@ -43,7 +43,9 @@ static int ccp_aes_cmac_complete(struct crypto_async_request *async_req,
 	} else
 		rctx->buf_count = 0;
 
-	memcpy(req->result, rctx->iv, digest_size);
+	/* Update result area if supplied */
+	if (req->result)
+		memcpy(req->result, rctx->iv, digest_size);
 
 e_free:
 	sg_free_table(&rctx->data_sg);
diff --git a/drivers/crypto/ccp/ccp-crypto-sha.c b/drivers/crypto/ccp/ccp-crypto-sha.c
index bf913cb..183d16e 100644
--- a/drivers/crypto/ccp/ccp-crypto-sha.c
+++ b/drivers/crypto/ccp/ccp-crypto-sha.c
@@ -74,6 +74,7 @@ static int ccp_sha_finish_hmac(struct crypto_async_request *async_req)
 	struct ahash_request *req = ahash_request_cast(async_req);
 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 	struct ccp_ctx *ctx = crypto_ahash_ctx(tfm);
+	struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req);
 	struct scatterlist sg[2];
 	unsigned int block_size =
 		crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
@@ -81,7 +82,7 @@ static int ccp_sha_finish_hmac(struct crypto_async_request *async_req)
 
 	sg_init_table(sg, ARRAY_SIZE(sg));
 	sg_set_buf(&sg[0], ctx->u.sha.opad, block_size);
-	sg_set_buf(&sg[1], req->result, digest_size);
+	sg_set_buf(&sg[1], rctx->ctx, digest_size);
 
 	return ccp_sync_hash(ctx->u.sha.hmac_tfm, req->result, sg,
 			     block_size + digest_size);
@@ -106,7 +107,9 @@ static int ccp_sha_complete(struct crypto_async_request *async_req, int ret)
 	} else
 		rctx->buf_count = 0;
 
-	memcpy(req->result, rctx->ctx, digest_size);
+	/* Update result area if supplied */
+	if (req->result)
+		memcpy(req->result, rctx->ctx, digest_size);
 
 	/* If we're doing an HMAC, we need to perform that on the final op */
 	if (rctx->final && ctx->u.sha.key_len)


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/