From: Ajit Kumar Pandey <AjitKumar.Pandey@xxxxxxx> [ Upstream commit 182b682b9ab1348e07ea1bf9d8f2505cc67f9237 ] When pcm stream is stopped "substream->runtime" pointer will be set to NULL by ALSA core. In case host received an ipc msg from firmware of type IPC_STREAM_POSITION after pcm stream is stopped, there will be kernel NULL pointer exception in ipc_period_elapsed(). This patch fixes it by adding NULL pointer check for "substream->runtime". Reviewed-by: Ranjani Sridharan <ranjani.sridharan@xxxxxxxxxxxxxxx> Signed-off-by: Ajit Kumar Pandey <AjitKumar.Pandey@xxxxxxx> Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20211216232422.345164-3-pierre-louis.bossart@xxxxxxxxxxxxxxx Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- sound/soc/sof/ipc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/sound/soc/sof/ipc.c b/sound/soc/sof/ipc.c index e6c53c6c470e4..ca30c506a0fd6 100644 --- a/sound/soc/sof/ipc.c +++ b/sound/soc/sof/ipc.c @@ -547,7 +547,8 @@ static void ipc_period_elapsed(struct snd_sof_dev *sdev, u32 msg_id) if (spcm->pcm.compress) snd_sof_compr_fragment_elapsed(stream->cstream); - else if (!stream->substream->runtime->no_period_wakeup) + else if (stream->substream->runtime && + !stream->substream->runtime->no_period_wakeup) /* only inform ALSA for period_wakeup mode */ snd_sof_pcm_period_elapsed(stream->substream); } -- 2.34.1