Received-SPF: pass (google.com: domain of linux-crypto-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Thara Gopinath <thara.gopinath@linaro.org>
To:     herbert@gondor.apana.org.au, davem@davemloft.net,
        bjorn.andersson@linaro.org
Cc:     ebiggers@google.com, ardb@kernel.org, sivaprak@codeaurora.org,
        linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH v7 05/11] crypto: qce: skcipher: Return error for zero length messages
Date:   Thu, 11 Feb 2021 15:01:22 -0500
Message-Id: <20210211200128.2886388-6-thara.gopinath@linaro.org>
In-Reply-To: <20210211200128.2886388-1-thara.gopinath@linaro.org>
References: <20210211200128.2886388-1-thara.gopinath@linaro.org>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Crypto engine BAM dma does not support 0 length data. Return unsupported
if zero length messages are passed for transformation.

Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
---

v5->v6:
	- Return 0 for zero length messages instead of -EOPNOTSUPP in the
	  cipher algorithms as pointed out by Eric Biggers.

 drivers/crypto/qce/skcipher.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/crypto/qce/skcipher.c b/drivers/crypto/qce/skcipher.c
index 8aeb741ca5a3..6b3dc3a9797c 100644
--- a/drivers/crypto/qce/skcipher.c
+++ b/drivers/crypto/qce/skcipher.c
@@ -8,6 +8,7 @@
 #include <linux/interrupt.h>
 #include <linux/moduleparam.h>
 #include <linux/types.h>
+#include <linux/errno.h>
 #include <crypto/aes.h>
 #include <crypto/internal/des.h>
 #include <crypto/internal/skcipher.h>
@@ -260,6 +261,10 @@ static int qce_skcipher_crypt(struct skcipher_request *req, int encrypt)
 	rctx->flags |= encrypt ? QCE_ENCRYPT : QCE_DECRYPT;
 	keylen = IS_XTS(rctx->flags) ? ctx->enc_keylen >> 1 : ctx->enc_keylen;
 
+	/* CE does not handle 0 length messages */
+	if (!req->cryptlen)
+		return 0;
+
 	/* qce is hanging when AES-XTS request len > QCE_SECTOR_SIZE and
 	 * is not a multiple of it; pass such requests to the fallback
 	 */
-- 
2.25.1