ALSA: hda/via: Avoid potential array out-of-bound in add_secret_dac_path()

snd_hda_get_connections() can return a negative error code.
It may lead to accessing 'conn' array at a negative index.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Signed-off-by: Artemii Karasev <[email protected]>
Fixes: 30b4503 ("ALSA: hda - Expose secret DAC-AA connection of some VIA codecs")
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Takashi Iwai <[email protected]>

Author: Artemii Karasev

sound/pci/hda/patch_via.c

@@ -819,6 +819,9 @@ static int add_secret_dac_path(struct hda_codec *codec)
 		return 0;
 	nums = snd_hda_get_connections(codec, spec->gen.mixer_nid, conn,
 				       ARRAY_SIZE(conn) - 1);
+	if (nums < 0)
+		return nums;
+
 	for (i = 0; i < nums; i++) {
 		if (get_wcaps_type(get_wcaps(codec, conn[i])) == AC_WID_AUD_OUT)
 			return 0;