[PATCH 5.10 55/57] ASoC: SOF: Intel: hda-dai: fix possible stream_tag leak

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

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

commit 1f810d2b6b2fbdc5279644d8b2c140b1f7c9d43d upstream.

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.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 sound/soc/sof/intel/hda-dai.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

--- a/sound/soc/sof/intel/hda-dai.c
+++ b/sound/soc/sof/intel/hda-dai.c
@@ -212,6 +212,10 @@ static int hda_link_hw_params(struct snd
 	int stream_tag;
 	int ret;
 
+	link = snd_hdac_ext_bus_get_link(bus, codec_dai->component->name);
+	if (!link)
+		return -EINVAL;
+
 	/* get stored dma data if resuming from system suspend */
 	link_dev = snd_soc_dai_get_dma_data(dai, substream);
 	if (!link_dev) {
@@ -232,10 +236,6 @@ static int hda_link_hw_params(struct snd
 	if (ret < 0)
 		return ret;
 
-	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(link_dev), substream->stream);