From:   Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
To:     stable@vger.kernel.org
Cc:     sashal@kernel.org, broonie@kernel.org, alsa-devel@alsa-project.org,
        pierre-louis.bossart@linux.intel.com,
        ranjani.sridharan@linux.intel.com, gregkh@linuxfoundation.org
Subject: [PATCH BACKPORT 6.0, 6.1] ASoC: SOF: Intel: hda-dai: fix possible stream_tag leak
Date:   Mon, 20 Feb 2023 13:16:58 +0200
Message-Id: <20230220111658.32256-1-peter.ujfalusi@linux.intel.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

[ Upstream commit 1f810d2b6b2fbdc5279644d8b2c140b1f7c9d43d ]

The reason for manual backport is that in 6.2 there were a naming cleanup
around hdac, link, hlink, for example snd_hdac_ext_bus_get_link is renamed
to snd_hdac_ext_bus_get_hlink_by_name in 6.2.

The HDaudio stream allocation is done first, and in a second step the
LOSIDV parameter is programmed for the multi-link used by a codec.

This leads to a possible stream_tag leak, e.g. if a DisplayAudio link
is not used. This would happen when a non-Intel graphics card is used
and userspace unconditionally uses the Intel Display Audio PCMs without
checking if they are connected to a receiver with jack controls.

We should first check that there is a valid multi-link entry to
configure before allocating a stream_tag. This change aligns the
dma_assign and dma_cleanup phases.

Cc: stable@vger.kernel.org # 6.1.x 6.0.x
Complements: b0cd60f3e9f5 ("ALSA/ASoC: hda: clarify bus_get_link() and bus_link_get() helpers")
Link: https://github.com/thesofproject/linux/issues/4151
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Link: https://lore.kernel.org/r/20230216162340.19480-1-peter.ujfalusi@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 sound/soc/sof/intel/hda-dai.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/sound/soc/sof/intel/hda-dai.c b/sound/soc/sof/intel/hda-dai.c
index 556e883a32ed..5f03ee390d54 100644
--- a/sound/soc/sof/intel/hda-dai.c
+++ b/sound/soc/sof/intel/hda-dai.c
@@ -216,6 +216,10 @@ static int hda_link_dma_hw_params(struct snd_pcm_substream *substream,
 	struct hdac_bus *bus = hstream->bus;
 	struct hdac_ext_link *link;
 
+	link = snd_hdac_ext_bus_get_link(bus, codec_dai->component->name);
+	if (!link)
+		return -EINVAL;
+
 	hext_stream = snd_soc_dai_get_dma_data(cpu_dai, substream);
 	if (!hext_stream) {
 		hext_stream = hda_link_stream_assign(bus, substream);
@@ -225,10 +229,6 @@ static int hda_link_dma_hw_params(struct snd_pcm_substream *substream,
 		snd_soc_dai_set_dma_data(cpu_dai, substream, (void *)hext_stream);
 	}
 
-	link = snd_hdac_ext_bus_get_link(bus, codec_dai->component->name);
-	if (!link)
-		return -EINVAL;
-
 	/* set the hdac_stream in the codec dai */
 	snd_soc_dai_set_stream(codec_dai, hdac_stream(hext_stream), substream->stream);
 
-- 
2.39.2