ASoC: dapm: Fix potential DAI widget pointer deref when linking DAIs

BugLink: https://bugs.launchpad.net/bugs/1836287
[ 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>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c
index a6b9cc9544a71f30880b739d6f1638f4e13c856e..622b3517966b419cf0535454fe476928712cf1fe 100644 (file)
--- a/sound/soc/soc-dapm.c
+++ b/sound/soc/soc-dapm.c
@@ -4035,6 +4035,13 @@ int snd_soc_dapm_link_dai_widgets(struct snd_soc_card *card)
                        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 */