From: Tzung-Bi Shih <tzungbi@kernel.org>
Date: Mon, 18 Jul 2022 05:09:14 +0000 (+0000)
Subject: platform/chrome: cros_ec_proto: return -EPROTO if empty payload
X-Git-Tag: block-6.0-2022-08-12~11^2~10
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=3e1c715ea179201372384fad738680d524600985;p=linux-2.6-block.git

platform/chrome: cros_ec_proto: return -EPROTO if empty payload

cros_ec_wait_until_complete() sends EC_CMD_GET_COMMS_STATUS which expects
to receive sizeof(struct ec_response_get_comms_status) from
cros_ec_xfer_command().

Return -EPROTO if cros_ec_xfer_command() returns 0.

Reviewed-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Link: https://lore.kernel.org/r/20220718050914.2267370-11-tzungbi@kernel.org
---

diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c
index 9dec475edc84..05d2e8765a66 100644
--- a/drivers/platform/chrome/cros_ec_proto.c
+++ b/drivers/platform/chrome/cros_ec_proto.c
@@ -163,6 +163,11 @@ static int cros_ec_wait_until_complete(struct cros_ec_device *ec_dev, uint32_t *
 		if (msg->result != EC_RES_SUCCESS)
 			return ret;
 
+		if (ret == 0) {
+			ret = -EPROTO;
+			break;
+		}
+
 		if (!(status->flags & EC_COMMS_STATUS_PROCESSING))
 			return ret;
 	}