[PATCH v7 05/11] crypto: qce: skcipher: Return error for zero length messages

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	[thread overview]
Message-ID: <20210211200128.2886388-6-thara.gopinath@linaro.org> (raw)
In-Reply-To: <20210211200128.2886388-1-thara.gopinath@linaro.org>

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

