[PATCH v2] ASoC: SOF: Intel: hda-dai: fix possible stream_tag leak

[PATCH v2] ASoC: SOF: Intel: hda-dai: fix possible stream_tag leak

[Peter Ujfalusi]

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

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>
---
Hi Mark,

I have added a Complements tag for now to force it follow the rename patch.
I need to check how far this needs to go back and I will send a backported
version later on.

b0cd60f3e9f5 is in 6.2-rc

Thanks,
Peter

 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 193b3e74820a..8d9c38d562d3 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,
 	sdev = snd_soc_component_get_drvdata(cpu_dai->component);
 	bus = sof_to_bus(sdev);
 
+	hlink = snd_hdac_ext_bus_get_hlink_by_name(bus, codec_dai->component->name);
+	if (!hlink)
+		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);
 	}
 
-	hlink = snd_hdac_ext_bus_get_hlink_by_name(bus, codec_dai->component->name);
-	if (!hlink)
-		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

Re: [PATCH v2] ASoC: SOF: Intel: hda-dai: fix possible stream_tag leak

[Mark Brown]

On Thu, 16 Feb 2023 18:23:40 +0200, Peter Ujfalusi wrote:
> 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.
> 
> [...]

Applied to

   broonie/sound.git for-next

Thanks!

[1/1] ASoC: SOF: Intel: hda-dai: fix possible stream_tag leak
      commit: 1f810d2b6b2fbdc5279644d8b2c140b1f7c9d43d

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark