crypto: talitos - check data blocksize in ablkcipher.

When data size is not a multiple of the alg's block size,
the SEC generates an error interrupt and dumps the registers.
And for NULL size, the SEC does just nothing and the interrupt
is awaited forever.

This patch ensures the data size is correct before submitting
the request to the SEC engine.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Fixes: 4de9d0b5 ("crypto: talitos - Add ablkcipher algorithms")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/talitos.c

@@ -1756,6 +1756,14 @@ static int ablkcipher_encrypt(struct ablkcipher_request *areq)
 	struct crypto_ablkcipher *cipher = crypto_ablkcipher_reqtfm(areq);
 	struct talitos_ctx *ctx = crypto_ablkcipher_ctx(cipher);
 	struct talitos_edesc *edesc;
+	unsigned int blocksize =
+			crypto_tfm_alg_blocksize(crypto_ablkcipher_tfm(cipher));
+
+	if (!areq->nbytes)
+		return 0;
+
+	if (areq->nbytes % blocksize)
+		return -EINVAL;
 
 	/* allocate extended descriptor */
 	edesc = ablkcipher_edesc_alloc(areq, true);
@@ -1773,6 +1781,14 @@ static int ablkcipher_decrypt(struct ablkcipher_request *areq)
 	struct crypto_ablkcipher *cipher = crypto_ablkcipher_reqtfm(areq);
 	struct talitos_ctx *ctx = crypto_ablkcipher_ctx(cipher);
 	struct talitos_edesc *edesc;
+	unsigned int blocksize =
+			crypto_tfm_alg_blocksize(crypto_ablkcipher_tfm(cipher));
+
+	if (!areq->nbytes)
+		return 0;
+
+	if (areq->nbytes % blocksize)
+		return -EINVAL;
 
 	/* allocate extended descriptor */
 	edesc = ablkcipher_edesc_alloc(areq, false);