4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Cezary Rojewski <cezary.rojewski@xxxxxxxxx> [ Upstream commit f93dc90c2e8ed664985e366aa6459ac83cdab236 ] While AudioDSP drivers assign streams exclusively of HOST or LINK type, nothing blocks a user to attempt to assign a COUPLED stream. As supplied substream instance may be a stub, what is the case when code-loading, such scenario ends with null-ptr-deref. Signed-off-by: Cezary Rojewski <cezary.rojewski@xxxxxxxxx> Link: https://lore.kernel.org/r/20231006102857.749143-2-cezary.rojewski@xxxxxxxxx Signed-off-by: Takashi Iwai <tiwai@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- sound/hda/hdac_stream.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/sound/hda/hdac_stream.c b/sound/hda/hdac_stream.c index eee422390d8e2..2569f82b6fa02 100644 --- a/sound/hda/hdac_stream.c +++ b/sound/hda/hdac_stream.c @@ -241,8 +241,10 @@ struct hdac_stream *snd_hdac_stream_assign(struct hdac_bus *bus, struct hdac_stream *res = NULL; /* make a non-zero unique key for the substream */ - int key = (substream->pcm->device << 16) | (substream->number << 2) | - (substream->stream + 1); + int key = (substream->number << 2) | (substream->stream + 1); + + if (substream->pcm) + key |= (substream->pcm->device << 16); list_for_each_entry(azx_dev, &bus->stream_list, list) { if (azx_dev->direction != substream->stream) -- 2.42.0
