crypto: hisilicon/sec - fix the aead software fallback for engine

mainline inclusion
from mainline-crypto-master
commit 0a2a464f
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I4W4WU
CVE: NA

--------------------------------

Due to the subreq pointer misuse the private context memory. The aead
soft crypto occasionally casues the OS panic as setting the 64K page.
Here is fix it.

Fixes: 6c46a329 ("crypto: hisilicon/sec - add fallback tfm...")
Signed-off-by: NKai Ye <yekai13@huawei.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NYang Shen <shenyang39@huawei.com>
Reviewed-by: NXiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

drivers/crypto/hisilicon/sec2/sec_crypto.c

@@ -2295,9 +2295,10 @@ static int sec_aead_soft_crypto(struct sec_ctx *ctx,
 				struct aead_request *aead_req,
 				bool encrypt)
 {
-	struct aead_request *subreq = aead_request_ctx(aead_req);
 	struct sec_auth_ctx *a_ctx = &ctx->a_ctx;
 	struct device *dev = ctx->dev;
+	struct aead_request *subreq;
+	int ret;
 
 	/* Kunpeng920 aead mode not support input 0 size */
 	if (!a_ctx->fallback_aead_tfm) {
@@ -2305,6 +2306,10 @@ static int sec_aead_soft_crypto(struct sec_ctx *ctx,
 		return -EINVAL;
 	}
 
+	subreq = aead_request_alloc(a_ctx->fallback_aead_tfm, GFP_KERNEL);
+	if (!subreq)
+		return -ENOMEM;
+
 	aead_request_set_tfm(subreq, a_ctx->fallback_aead_tfm);
 	aead_request_set_callback(subreq, aead_req->base.flags,
 				  aead_req->base.complete, aead_req->base.data);
@@ -2312,8 +2317,13 @@ static int sec_aead_soft_crypto(struct sec_ctx *ctx,
 			       aead_req->cryptlen, aead_req->iv);
 	aead_request_set_ad(subreq, aead_req->assoclen);
 
-	return encrypt ? crypto_aead_encrypt(subreq) :
-		   crypto_aead_decrypt(subreq);
+	if (encrypt)
+		ret = crypto_aead_encrypt(subreq);
+	else
+		ret = crypto_aead_decrypt(subreq);
+	aead_request_free(subreq);
+
+	return ret;
 }
 
 static int sec_aead_crypto(struct aead_request *a_req, bool encrypt)