[PATCH 3.18 045/120] ASoC: dapm: Fix potential DAI widget pointer deref when linking DAIs

Greg Kroah-Hartman
2018-10-11T15:37:42Z

From: Liam Girdwood <liam.r.girdwood@linux.intel.com>

[ Upstream commit e01b4f624278d5efe5fb5da585ca371947b16680 ]

Sometime a component or topology may configure a DAI widget with no
private data leading to a dev_dbg() dereferencne of this data.

Fix this to check for non NULL private data and let users know if widget
is missing DAI.

Signed-off-by: Liam Girdwood <liam.r.girdwood@linux.intel.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>
---
sound/soc/soc-dapm.c | 7 +++++++
1 file changed, 7 insertions(+)

--- a/sound/soc/soc-dapm.c
+++ b/sound/soc/soc-dapm.c
@@ -3400,6 +3400,13 @@ int snd_soc_dapm_link_dai_widgets(struct
continue;
}

+ /* let users know there is no DAI to link */
+ if (!dai_w->priv) {
+ dev_dbg(card->dev, "dai widget %s has no DAI\n",
+ dai_w->name);
+ continue;
+ }
+
dai = dai_w->priv;

/* ...find all widgets with the same stream and link them */