ASoC: hda: fix unbalanced codec dev refcount for HDA_DEV_ASOC
authorRanjani Sridharan <ranjani.sridharan@linux.intel.com>
Fri, 31 May 2019 16:01:37 +0000 (09:01 -0700)
committerMark Brown <broonie@kernel.org>
Mon, 3 Jun 2019 16:43:23 +0000 (17:43 +0100)
HDA_DEV_ASOC type codec device refcounts are managed differently
from HDA_DEV_LEGACY devices. The refcount is released explicitly
in snd_hdac_ext_bus_device_remove() for ASOC type devices.
So, remove the put_device() call in snd_hda_codec_dev_free()
for such devices to make the refcount balanced. This will prevent
the NULL pointer exception when the codec driver is released
after the card is freed.

Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
sound/pci/hda/hda_codec.c

index ec0b8595eb4da448a51d3376c9913e96f09e3075..6cdec64dc68ad0da42ddc6fa94cc2ad2029e38d2 100644 (file)
@@ -834,7 +834,14 @@ static int snd_hda_codec_dev_free(struct snd_device *device)
        codec->in_freeing = 1;
        snd_hdac_device_unregister(&codec->core);
        codec_display_power(codec, false);
-       put_device(hda_codec_dev(codec));
+
+       /*
+        * In the case of ASoC HD-audio bus, the device refcount is released in
+        * snd_hdac_ext_bus_device_remove() explicitly.
+        */
+       if (codec->core.type == HDA_DEV_LEGACY)
+               put_device(hda_codec_dev(codec));
+
        return 0;
 }