ASoC: SOF: Correct sps->stream and cstream nullity management

Hi,

The nullity of sps->cstream needs to be checked in sof_ipc_msg_data() and not assume that it is not NULL.
The sps->stream must be cleared to NULL on close since this is used as a check to see if we have active PCM stream.

Regards,
Peter
---
Peter Ujfalusi (2):
ASoC: SOF: stream-ipc: Check for cstream nullity in sof_ipc_msg_data()
ASoC: SOF: pcm: Clear the susbstream pointer to NULL on close

 sound/soc/sof/pcm.c        | 2 ++
 sound/soc/sof/stream-ipc.c | 6 +++++-
 2 files changed, 7 insertions(+), 1 deletion(-)

2.47.0

The nullity of sps->cstream should be checked similarly as it is done in sof_set_stream_data_offset() function.
Assuming that it is not NULL if sps->stream is NULL is incorrect and can lead to NULL pointer dereference.

---
 sound/soc/sof/stream-ipc.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

index 794c7bbccbaf..8262443ac89a 100644
@@ -43,7 +43,7 @@ int sof_ipc_msg_data(struct snd_sof_dev *sdev,
 				return -ESTRPIPE;
 
 			posn_offset = stream->posn_offset;
-		} else {
+		} else if (sps->cstream) {
 
 			struct sof_compr_stream *sstream = sps->cstream->runtime->private_data;
 

@@ -51,6 +51,10 @@ int sof_ipc_msg_data(struct snd_sof_dev *sdev,
 				return -ESTRPIPE;
 
 			posn_offset = sstream->posn_offset;
+
+		} else {
+			dev_err(sdev->dev, "%s: No stream opened\n", __func__);
+			return -EINVAL;
 		}
 
 		snd_sof_dsp_mailbox_read(sdev, posn_offset, p, sz);

2.47.0

The spcm->stream[substream->stream].substream is set during open and was left untouched. After the first PCM stream it will never be NULL and we have code which checks for substream NULLity as indication if the stream is active or not.
For the compressed cstream pointer the same has been done, this change will correct the handling of PCM streams.

---
 sound/soc/sof/pcm.c | 2 ++
 1 file changed, 2 insertions(+)

index 35a7462d8b69..c5c6353f18ce 100644
@@ -511,6 +511,8 @@ static int sof_pcm_close(struct snd_soc_component *component,
 		 */
 	}
 
+	spcm->stream[substream->stream].substream = NULL;
+
 	return 0;
 }
 

2.47.0