[PATCH 4.18 063/135] ASoC: dapm: Fix NULL pointer deference on CODEC to CODEC DAIs

Greg Kroah-Hartman
2018-10-16T17:13:05Z

From: Charles Keepax <ckeepax@opensource.cirrus.com>

[ Upstream commit 249dc49576fc953a7378b916c6a6d47ea81e4da2 ]

Commit a655de808cbde ("ASoC: core: Allow topology to override
machine driver FE DAI link config.") caused soc_dai_hw_params to
be come dependent on the substream private_data being set with
a pointer to the snd_soc_pcm_runtime. Currently, CODEC to CODEC
links don't set this, which causes a NULL pointer dereference:

[<4069de54>] (soc_dai_hw_params) from
[<40694b68>] (snd_soc_dai_link_event+0x1a0/0x380)

Since the ASoC core in general assumes that the substream
private_data will be set to a pointer to the snd_soc_pcm_runtime,
update the CODEC to CODEC links to respect this.

Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
include/sound/soc-dapm.h | 1 +
sound/soc/soc-core.c | 4 ++--
sound/soc/soc-dapm.c | 4 ++++
3 files changed, 7 insertions(+), 2 deletions(-)

--- a/include/sound/soc-dapm.h
+++ b/include/sound/soc-dapm.h
@@ -410,6 +410,7 @@ int snd_soc_dapm_new_dai_widgets(struct
int snd_soc_dapm_link_dai_widgets(struct snd_soc_card *card);
void snd_soc_dapm_connect_dai_link_widgets(struct snd_soc_card *card);
int snd_soc_dapm_new_pcm(struct snd_soc_card *card,
+ struct snd_soc_pcm_runtime *rtd,
const struct snd_soc_pcm_stream *params,
unsigned int num_params,
struct snd_soc_dapm_widget *source,
--- a/sound/soc/soc-core.c
+++ b/sound/soc/soc-core.c
@@ -1430,7 +1430,7 @@ static int soc_link_dai_widgets(struct s
sink = codec_dai->playback_widget;
source = cpu_dai->capture_widget;
if (sink && source) {
- ret = snd_soc_dapm_new_pcm(card, dai_link->params,
+ ret = snd_soc_dapm_new_pcm(card, rtd, dai_link->params,
dai_link->num_params,
source, sink);
if (ret != 0) {
@@ -1443,7 +1443,7 @@ static int soc_link_dai_widgets(struct s
sink = cpu_dai->playback_widget;
source = codec_dai->capture_widget;
if (sink && source) {
- ret = snd_soc_dapm_new_pcm(card, dai_link->params,
+ ret = snd_soc_dapm_new_pcm(card, rtd, dai_link->params,
dai_link->num_params,
source, sink);
if (ret != 0) {
--- a/sound/soc/soc-dapm.c
+++ b/sound/soc/soc-dapm.c
@@ -3658,6 +3658,7 @@ static int snd_soc_dai_link_event(struct
{
struct snd_soc_dapm_path *source_p, *sink_p;
struct snd_soc_dai *source, *sink;
+ struct snd_soc_pcm_runtime *rtd = w->priv;
const struct snd_soc_pcm_stream *config = w->params + w->params_select;
struct snd_pcm_substream substream;
struct snd_pcm_hw_params *params = NULL;
@@ -3717,6 +3718,7 @@ static int snd_soc_dai_link_event(struct
goto out;
}
substream.runtime = runtime;
+ substream.private_data = rtd;

switch (event) {
case SND_SOC_DAPM_PRE_PMU:
@@ -3901,6 +3903,7 @@ outfree_w_param:
}

int snd_soc_dapm_new_pcm(struct snd_soc_card *card,
+ struct snd_soc_pcm_runtime *rtd,
const struct snd_soc_pcm_stream *params,
unsigned int num_params,
struct snd_soc_dapm_widget *source,
@@ -3969,6 +3972,7 @@ int snd_soc_dapm_new_pcm(struct snd_soc_

w->params = params;
w->num_params = num_params;
+ w->priv = rtd;

ret = snd_soc_dapm_add_path(&card->dapm, source, w, NULL, NULL);
if (ret)