ALSA: hda: Skip codec shutdown in case the codec is not registered

ujfalusi · tiwai · commit 1c7f0e349aa5 · 2022-02-01T15:18:17.000+01:00
If the codec->registered is not set then it means that pm_runtime is not yet enabled and the codec->pcm_list_head has not been initialized. The access to the not initialized pcm_list_head will lead a kernel crash during shutdown. Reported-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com> Tested-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com> Fixes: b98444e ("ALSA: hda: Suspend codec at shutdown") Link: https://lore.kernel.org/r/20220201112144.29411-1-peter.ujfalusi@linux.intel.com Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c
@@ -3000,6 +3000,10 @@ void snd_hda_codec_shutdown(struct hda_codec *codec)
 {
 	struct hda_pcm *cpcm;
 
+	/* Skip the shutdown if codec is not registered */
+	if (!codec->registered)
+		return;
+
 	list_for_each_entry(cpcm, &codec->pcm_list_head, list)
 		snd_pcm_suspend_all(cpcm->pcm);
 

Original file line number	Diff line number	Diff line change
`@@ -3000,6 +3000,10 @@ void snd_hda_codec_shutdown(struct hda_codec *codec)`
`3000`	`3000`	`{`
`3001`	`3001`	`struct hda_pcm *cpcm;`
`3002`	`3002`
	`3003`	`+ /* Skip the shutdown if codec is not registered */`
	`3004`	`+ if (!codec->registered)`
	`3005`	`+ return;`
	`3006`	`+`
`3003`	`3007`	`list_for_each_entry(cpcm, &codec->pcm_list_head, list)`
`3004`	`3008`	`snd_pcm_suspend_all(cpcm->pcm);`
`3005`	`3009`