[PATCH 3.16 089/148] ASoC: Jack: Fix NULL pointer dereference in snd_soc_jack_report

[Ben Hutchings]

3.16.82-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Pawel Harlozinski <pawel.harlozinski@xxxxxxxxxxxxxxx>

commit 8f157d4ff039e03e2ed4cb602eeed2fd4687a58f upstream.

Check for existance of jack before tracing.
NULL pointer dereference has been reported by KASAN while unloading
machine driver (snd_soc_cnl_rt274).

Signed-off-by: Pawel Harlozinski <pawel.harlozinski@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20191112130237.10141-1-pawel.harlozinski@xxxxxxxxxxxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 sound/soc/soc-jack.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

--- a/sound/soc/soc-jack.c
+++ b/sound/soc/soc-jack.c
@@ -69,10 +69,9 @@ void snd_soc_jack_report(struct snd_soc_
 	unsigned int sync = 0;
 	int enable;
 
-	trace_snd_soc_jack_report(jack, mask, status);
-
 	if (!jack)
 		return;
+	trace_snd_soc_jack_report(jack, mask, status);
 
 	codec = jack->codec;
 	dapm =  &codec->dapm;