ASoC: SOF: Intel: hda-dai: fix possible stream_tag leak

[ Upstream commit 1f810d2b6b2fbdc5279644d8b2c140b1f7c9d43d ]

There were just too many code changes since 5.4 stable to prevent clean picking the fix from mainline.

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: [email protected] # 5.4.x
Complements: b0cd60f3e9f5 ("ALSA/ASoC: hda: clarify bus_get_link() and bus_link_get() helpers")

---
 sound/soc/sof/intel/hda-dai.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

index b3cdd10c83ae..c30e450fa970 100644
@@ -211,6 +211,10 @@ static int hda_link_hw_params(struct snd_pcm_substream *substream,
 	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) {

@@ -231,10 +235,6 @@ static int hda_link_hw_params(struct snd_pcm_substream *substream,
 	if (ret < 0)
 		return ret;
 
-	link = snd_hdac_ext_bus_get_link(bus, codec_dai->component->name);
-	if (!link)
-		return -EINVAL;
-
 	/* set the stream tag in the codec dai dma params */
 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 		snd_soc_dai_set_tdm_slot(codec_dai, stream_tag, 0, 0, 0);

2.39.2

Thanks, all backports now queued up.

greg k-h