[alsa-devel] [PATCH 050/112] ALSA: hda - Fix NULL dereference in snd_hda_gen_build_controls()

[Takashi Iwai]

When no controls are assigned in the parser (e.g. no analog path),
spec->kctls.list is still NULL.  We need to check it before passing to
snd_hda_add_new_ctls().

Signed-off-by: Takashi Iwai <tiwai at suse.de>
---
 sound/pci/hda/hda_generic.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/sound/pci/hda/hda_generic.c b/sound/pci/hda/hda_generic.c
index e512cab..364ec06 100644
--- a/sound/pci/hda/hda_generic.c
+++ b/sound/pci/hda/hda_generic.c
@@ -2906,9 +2906,11 @@ int snd_hda_gen_build_controls(struct hda_codec *codec)
 	struct hda_gen_spec *spec = codec->spec;
 	int err;
 
-	err = snd_hda_add_new_ctls(codec, spec->kctls.list);
-	if (err < 0)
-		return err;
+	if (spec->kctls.used) {
+		err = snd_hda_add_new_ctls(codec, spec->kctls.list);
+		if (err < 0)
+			return err;
+	}
 
 	if (spec->multiout.dig_out_nid) {
 		err = snd_hda_create_dig_out_ctls(codec,
-- 
1.8.0.1