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

From: Artemii Karasev
Date: Thu Jan 19 2023 - 03:23:39 EST


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 <karasev@xxxxxxxxx>
Fixes: 30b4503378c9 ("ALSA: hda - Expose secret DAC-AA connection of some VIA codecs")
---
sound/pci/hda/patch_via.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/sound/pci/hda/patch_via.c b/sound/pci/hda/patch_via.c
index aea7fae2ca4b..2994f85bc1b9 100644
--- a/sound/pci/hda/patch_via.c
+++ b/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;
--
2.25.1