linux-kernel - [PATCH 5.4 204/340] soundwire: cadence: fix ACK/NAK handling

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20210301161058.347317488@linuxfoundation.org>
Date:   Mon,  1 Mar 2021 17:12:28 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org,
        Pierre-Louis Bossart <pierre-louis.bossart@...ux.intel.com>,
        Bard Liao <yung-chuan.liao@...ux.intel.com>,
        Vinod Koul <vkoul@...nel.org>, Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.4 204/340] soundwire: cadence: fix ACK/NAK handling

From: Pierre-Louis Bossart <pierre-louis.bossart@...ux.intel.com>

[ Upstream commit db9d9f944f95e7f3aa60ac00cbd502415152c421 ]

The existing code reports a NAK only when ACK=0
This is not aligned with the SoundWire 1.x specifications.

Table 32 in the SoundWire 1.2 specification shows that a Device shall
not set NAK=1 if ACK=1. But Table 33 shows the Combined Response
may very well be NAK=1/ACK=1, e.g. if another Device than the one
addressed reports a parity error.

NAK=1 signals a 'Command_Aborted', regardless of the ACK bit value.

Move the tests for NAK so that the NAK=1/ACK=1 combination is properly
detected according to the specification.

Fixes: 956baa1992f9a ('soundwire: cdns: Add sdw_master_ops and IO transfer support')
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@...ux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@...ux.intel.com>
Link: https://lore.kernel.org/r/20210115053738.22630-5-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@...nel.org>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 drivers/soundwire/cadence_master.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c
index e3d06330d1258..f7d0f63921dc2 100644
--- a/drivers/soundwire/cadence_master.c
+++ b/drivers/soundwire/cadence_master.c
@@ -368,10 +368,10 @@ cdns_fill_msg_resp(struct sdw_cdns *cdns,
 		if (!(cdns->response_buf[i] & CDNS_MCP_RESP_ACK)) {
 			no_ack = 1;
 			dev_dbg_ratelimited(cdns->dev, "Msg Ack not received\n");
-			if (cdns->response_buf[i] & CDNS_MCP_RESP_NACK) {
-				nack = 1;
-				dev_err_ratelimited(cdns->dev, "Msg NACK received\n");
-			}
+		}
+		if (cdns->response_buf[i] & CDNS_MCP_RESP_NACK) {
+			nack = 1;
+			dev_err_ratelimited(cdns->dev, "Msg NACK received\n");
 		}
 	}
 
-- 
2.27.0