crypto: tegra - Fix IV usage for AES ECB

[ Upstream commit 1ddaff4 ]

Modifying the crypto_request turns out to be not the right way to handle
the stale value issue with the IV. Though the IV is not used for AES ECB,
it eventually get used in algorithms like LRW in the next step after
AES ECB encryption/decryption. Setting req->iv to NULL breaks the
implementation of such algorithms. Hence modify only the local reqctx
to check for IV.

Fixes: bde5582 ("crypto: tegra - Set IV to NULL explicitly for AES ECB")
Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Author: Akhil R

drivers/crypto/tegra/tegra-se-aes.c

@@ -263,7 +263,7 @@ static int tegra_aes_do_one_req(struct crypto_engine *engine, void *areq)
 	unsigned int cmdlen;
 	int ret;
 
-	rctx->iv = (u32 *)req->iv;
+	rctx->iv = (ctx->alg == SE_ALG_ECB) ? NULL : (u32 *)req->iv;
 	rctx->len = req->cryptlen;
 
 	/* Pad input to AES Block size */
@@ -443,9 +443,6 @@ static int tegra_aes_crypt(struct skcipher_request *req, bool encrypt)
 	if (!req->cryptlen)
 		return 0;
 
-	if (ctx->alg == SE_ALG_ECB)
-		req->iv = NULL;
-
 	rctx->encrypt = encrypt;
 	rctx->config = tegra234_aes_cfg(ctx->alg, encrypt);
 	rctx->crypto_config = tegra234_aes_crypto_cfg(ctx->alg, encrypt);