[PATCH v5 15/15] crypto: ti - Change lengths in AEAD to u64 to avoid potential overflows

Change assoclen, cryptlen, authsize from unsigned int to u64 to avoid
overflow when they are added (in TAG offset and padding length
calculation)

Fixes: 37b902c603042 ("crypto: ti - Add support for AES-GCM in DTHEv2 driver")
Signed-off-by: T Pratham <[email protected]>
---
 drivers/crypto/ti/dthev2-aes.c | 28 +++++++++++++++++-----------
 1 file changed, 17 insertions(+), 11 deletions(-)

diff --git a/drivers/crypto/ti/dthev2-aes.c b/drivers/crypto/ti/dthev2-aes.c
index 9b982ca4a7730..ca87aacc39c5d 100644
--- a/drivers/crypto/ti/dthev2-aes.c
+++ b/drivers/crypto/ti/dthev2-aes.c
@@ -756,6 +756,9 @@ static int dthe_aead_enc_get_tag(struct aead_request *req)
 	struct dthe_tfm_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
 	struct dthe_aes_req_ctx *rctx = aead_request_ctx(req);
 	u32 tag[AES_BLOCK_WORDS];
+	u64 assoclen = req->assoclen;
+	u64 cryptlen = req->cryptlen;
+	u64 authsize = ctx->authsize;
 	int nents;
 	int ret;
 
@@ -763,12 +766,12 @@ static int dthe_aead_enc_get_tag(struct aead_request *req)
 	if (ret)
 		return ret;
 
-	nents = sg_nents_for_len(req->dst, req->cryptlen + req->assoclen + ctx->authsize);
+	nents = sg_nents_for_len(req->dst, cryptlen + assoclen + authsize);
 	if (nents < 0)
 		return nents;
 
-	sg_pcopy_from_buffer(req->dst, nents, tag, ctx->authsize,
-			     req->assoclen + req->cryptlen);
+	sg_pcopy_from_buffer(req->dst, nents, tag, authsize,
+			     assoclen + cryptlen);
 
 	return 0;
 }
@@ -779,6 +782,9 @@ static int dthe_aead_dec_verify_tag(struct aead_request *req)
 	struct dthe_aes_req_ctx *rctx = aead_request_ctx(req);
 	u32 tag_out[AES_BLOCK_WORDS];
 	u32 tag_in[AES_BLOCK_WORDS];
+	u64 assoclen = req->assoclen;
+	u64 cryptlen = req->cryptlen;
+	u64 authsize = ctx->authsize;
 	int nents;
 	int ret;
 
@@ -786,14 +792,14 @@ static int dthe_aead_dec_verify_tag(struct aead_request *req)
 	if (ret)
 		return ret;
 
-	nents = sg_nents_for_len(req->src, req->assoclen + req->cryptlen);
+	nents = sg_nents_for_len(req->src, assoclen + cryptlen);
 	if (nents < 0)
 		return nents;
 
-	sg_pcopy_to_buffer(req->src, nents, tag_in, ctx->authsize,
-			   req->assoclen + req->cryptlen - ctx->authsize);
+	sg_pcopy_to_buffer(req->src, nents, tag_in, authsize,
+			   assoclen + cryptlen - authsize);
 
-	if (crypto_memneq(tag_in, tag_out, ctx->authsize))
+	if (crypto_memneq(tag_in, tag_out, authsize))
 		return -EBADMSG;
 	else
 		return 0;
@@ -887,10 +893,10 @@ static int dthe_aead_run(struct crypto_engine *engine, void *areq)
 	struct dthe_aes_req_ctx *rctx = aead_request_ctx(req);
 	struct dthe_data *dev_data = rctx->dev_data;
 
-	unsigned int cryptlen = req->cryptlen;
-	unsigned int assoclen = req->assoclen;
-	unsigned int authsize = ctx->authsize;
-	unsigned int unpadded_cryptlen;
+	u64 cryptlen = req->cryptlen;
+	u64 assoclen = req->assoclen;
+	u64 authsize = ctx->authsize;
+	u64 unpadded_cryptlen;
 	struct scatterlist *src = NULL;
 	struct scatterlist *dst = NULL;
 	struct scatterlist *aad_sg = NULL;
-- 
2.34.1