crypto: nx - Fix reentrancy bugs

This patch fixes a host of reentrancy bugs in the nx driver.  The
following algorithms are affected:

* CCM
* GCM
* CTR
* XCBC
* SHA256
* SHA512

The crypto API allows a single transform to be used by multiple
threads simultaneously.  For example, IPsec will use a single tfm
to process packets for a given SA.  As packets may arrive on
multiple CPUs that tfm must be reentrant.

The nx driver does try to deal with this by using a spin lock.
Unfortunately only the basic AES/CBC/ECB algorithms do this in
the correct way.

The symptom of these bugs may range from the generation of incorrect
output to memory corruption.

Cc: stable@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/nx/nx-aes-ccm.c

@@ -494,8 +494,9 @@ out:
 static int ccm4309_aes_nx_encrypt(struct aead_request *req)
 {
 	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm);
+	struct nx_gcm_rctx *rctx = aead_request_ctx(req);
 	struct blkcipher_desc desc;
-	u8 *iv = nx_ctx->priv.ccm.iv;
+	u8 *iv = rctx->iv;
 
 	iv[0] = 3;
 	memcpy(iv + 1, nx_ctx->priv.ccm.nonce, 3);
@@ -525,8 +526,9 @@ static int ccm_aes_nx_encrypt(struct aead_request *req)
 static int ccm4309_aes_nx_decrypt(struct aead_request *req)
 {
 	struct nx_crypto_ctx *nx_ctx = crypto_tfm_ctx(req->base.tfm);
+	struct nx_gcm_rctx *rctx = aead_request_ctx(req);
 	struct blkcipher_desc desc;
-	u8 *iv = nx_ctx->priv.ccm.iv;
+	u8 *iv = rctx->iv;
 
 	iv[0] = 3;
 	memcpy(iv + 1, nx_ctx->priv.ccm.nonce, 3);