On 2020-02-18 17:45, Pierre-Louis Bossart wrote:
On 2/18/20 8:10 AM, Cezary Rojewski wrote:
Field "substream" gets assigned during stream setup in hda_dsp_pcm_hw_params() but it is never cleared afterwards during hda_dsp_pcm_close(). Now, any non-pcm operation e.g.: compress can mistakenly make use of that pointer as it's bypassing all "if (s->substream)" checks.
Nulling the pointer during close operation ensures no wild pointers are left behind.
Fixes: cdae3b9a47aa ("ASoC: SOF: Intel: Add Intel specific HDA PCM operations") Signed-off-by: Cezary Rojewski cezary.rojewski@intel.com
sound/soc/sof/intel/hda-pcm.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/sound/soc/sof/intel/hda-pcm.c b/sound/soc/sof/intel/hda-pcm.c index a46a6baa1c3f..4b3a89cf20e7 100644 --- a/sound/soc/sof/intel/hda-pcm.c +++ b/sound/soc/sof/intel/hda-pcm.c @@ -246,5 +246,6 @@ int hda_dsp_pcm_close(struct snd_sof_dev *sdev, /* unbinding pcm substream to hda stream */ substream->runtime->private_data = NULL; + hstream->substream = NULL; return 0; }
Humm, yes we should clean this, but wondering if the close() operation is the right place. Doing this is hda_dsp_stream_hw_free() sounds more logical to me?
Ain't hda-pcm.c the best place for it as "hstream->substream = substream" happens there too? If the cleanup is to be done in _hw_free(), then I'd expect the same to happen to the original assignments. Doubt we want to do the later so.. _close() for the win?
In general the existing hstream->substream initialization looks kinda disconnected from the actual stream assignment code - _stream_get() - as if the duties of the state machine were shared.
Czarek