[PATCH 5.16 056/126] ALSA: hda: Skip codec shutdown in case the codec is not registered

[Greg Kroah-Hartman]

From: Peter Ujfalusi <peter.ujfalusi@xxxxxxxxxxxxxxx>

commit 1c7f0e349aa5f8f80b1cac3d4917405332e14cdf upstream.

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@xxxxxxxxxxxxxxx>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@xxxxxxxxxxxxxxx>
Tested-by: Guennadi Liakhovetski <guennadi.liakhovetski@xxxxxxxxxxxxxxx>
Fixes: b98444ed597d ("ALSA: hda: Suspend codec at shutdown")
Link: https://lore.kernel.org/r/20220201112144.29411-1-peter.ujfalusi@xxxxxxxxxxxxxxx
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 sound/pci/hda/hda_codec.c |    4 ++++
 1 file changed, 4 insertions(+)

--- 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_c
 {
 	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);