[PATCH 4.16 11/31] crypto: ccp - Fill the result buffer only on digest, finup, and final ops

[Greg Kroah-Hartman]

4.16-stable review patch.  If anyone has any objections, please let me know.

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

From: Gary R Hook <gary.hook@xxxxxxx>

commit 0ee991be4cdd88587aedbf68cdacd1765f57236a upstream.

Any change to the result buffer should only happen on final, finup
and digest operations. Changes to the buffer for update, import, export,
etc, are not allowed.

Fixes: 66d7b9f6175e ("crypto: testmgr - test misuse of result in ahash")
Signed-off-by: Gary R Hook <gary.hook@xxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/crypto/ccp/ccp-crypto-aes-cmac.c |    2 +-
 drivers/crypto/ccp/ccp-crypto-sha.c      |    2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/crypto/ccp/ccp-crypto-aes-cmac.c
+++ b/drivers/crypto/ccp/ccp-crypto-aes-cmac.c
@@ -46,7 +46,7 @@ static int ccp_aes_cmac_complete(struct
 	}
 
 	/* Update result area if supplied */
-	if (req->result)
+	if (req->result && rctx->final)
 		memcpy(req->result, rctx->iv, digest_size);
 
 e_free:
--- a/drivers/crypto/ccp/ccp-crypto-sha.c
+++ b/drivers/crypto/ccp/ccp-crypto-sha.c
@@ -47,7 +47,7 @@ static int ccp_sha_complete(struct crypt
 	}
 
 	/* Update result area if supplied */
-	if (req->result)
+	if (req->result && rctx->final)
 		memcpy(req->result, rctx->ctx, digest_size);
 
 e_free: