ALSA: hda - Fix NULL-derefence with a single mic in STAC auto-mic detection
When only one mic is available and it's an analog mic, the current
IDT/STAC parser may give an Oops.
Reference: bko#25692
https://bugzilla.kernel.org/show_bug.cgi?id=25692
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Cc: <stable@kernel.org>
diff --git a/sound/pci/hda/patch_sigmatel.c b/sound/pci/hda/patch_sigmatel.c
index c8d812e..4ab019d 100644
--- a/sound/pci/hda/patch_sigmatel.c
+++ b/sound/pci/hda/patch_sigmatel.c
@@ -3594,7 +3594,7 @@
if (check_mic_pin(codec, spec->dmic_nids[i],
&fixed, &ext, &dock))
return 0;
- if (!fixed && !ext && !dock)
+ if (!fixed || (!ext && !dock))
return 0; /* no input to switch */
if (!(get_wcaps(codec, ext) & AC_WCAP_UNSOL_CAP))
return 0; /* no unsol support */
