From: Julia Lawall julia@diku.dk
If the NULL test on jack is needed, then the derefernce should be after the NULL test.
A simplified version of the semantic match that detects this problem is as follows (http://coccinelle.lip6.fr/):
// <smpl> @match exists@ expression x, E; identifier fld; @@
* x->fld ... when != (x = E|&x) * x == NULL // </smpl>
Signed-off-by: Julia Lawall julia@diku.dk
--- sound/soc/soc-jack.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-)
diff --git a/sound/soc/soc-jack.c b/sound/soc/soc-jack.c index 1d455ab..1212414 100644 --- a/sound/soc/soc-jack.c +++ b/sound/soc/soc-jack.c @@ -58,7 +58,7 @@ EXPORT_SYMBOL_GPL(snd_soc_jack_new); */ void snd_soc_jack_report(struct snd_soc_jack *jack, int status, int mask) { - struct snd_soc_codec *codec = jack->card->codec; + struct snd_soc_codec *codec; struct snd_soc_jack_pin *pin; int enable; int oldstatus; @@ -67,6 +67,7 @@ void snd_soc_jack_report(struct snd_soc_jack *jack, int status, int mask) WARN_ON_ONCE(!jack); return; } + codec = jack->card->codec;
mutex_lock(&codec->mutex);