[PATCH] crypto: fix potential null pointer dereference on pointer dd

[Chengfeng Ye]

The return pointer of atmel_sha_find_dev could
be null, there could be potential null-deref issue.
Fix this by adding a null check.

Signed-off-by: Chengfeng Ye <cyeaa@xxxxxxxxxxxxxx>
---
 drivers/crypto/atmel-sha.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/crypto/atmel-sha.c b/drivers/crypto/atmel-sha.c
index 1b13f601fd95..f6ea5aadb86a 100644
--- a/drivers/crypto/atmel-sha.c
+++ b/drivers/crypto/atmel-sha.c
@@ -430,6 +430,9 @@ static int atmel_sha_init(struct ahash_request *req)
 	struct atmel_sha_reqctx *ctx = ahash_request_ctx(req);
 	struct atmel_sha_dev *dd = atmel_sha_find_dev(tctx);
 
+	if (!dd)
+		return -EINVAL;
+
 	ctx->dd = dd;
 
 	ctx->flags = 0;
-- 
2.17.1