[PATCH 4.16 101/161] crypto: inside-secure - do not process request if no command was issued

[Greg Kroah-Hartman]

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

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

From: Antoine Tenart <antoine.tenart@xxxxxxxxxxx>

[ Upstream commit 95831ceafc0de7d94a5fe86ebb1c2042317cc2cd ]

This patch adds a check in the SafeXcel dequeue function, to avoid
processing request further if no hardware command was issued. This can
happen in certain cases where the ->send() function caches all the data
that would have been send.

Fixes: 809778e02cd4 ("crypto: inside-secure - fix hash when length is a multiple of a block")
Signed-off-by: Antoine Tenart <antoine.tenart@xxxxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/crypto/inside-secure/safexcel.c |    9 +++++++++
 1 file changed, 9 insertions(+)

--- a/drivers/crypto/inside-secure/safexcel.c
+++ b/drivers/crypto/inside-secure/safexcel.c
@@ -490,6 +490,15 @@ handle_req:
 		if (backlog)
 			backlog->complete(backlog, -EINPROGRESS);
 
+		/* In case the send() helper did not issue any command to push
+		 * to the engine because the input data was cached, continue to
+		 * dequeue other requests as this is valid and not an error.
+		 */
+		if (!commands && !results) {
+			kfree(request);
+			continue;
+		}
+
 		spin_lock_bh(&priv->ring[ring].egress_lock);
 		list_add_tail(&request->list, &priv->ring[ring].list);
 		spin_unlock_bh(&priv->ring[ring].egress_lock);