[PATCH 3.19.y-ckt 063/196] ALSA: hda - Fix static checker warning in patch_hdmi.c

From: Kamal Mostafa
Date: Tue Mar 08 2016 - 20:09:26 EST

3.19.8-ckt16 -stable review patch. If anyone has any objections, please let me know.


From: David Henningsson <david.henningsson@xxxxxxxxxxxxx>

commit 360a8245680053619205a3ae10e6bfe624a5da1d upstream.

The static checker warning is:

sound/pci/hda/patch_hdmi.c:460 hdmi_eld_ctl_get()
error: __memcpy() 'eld->eld_buffer' too small (256 vs 512)

I have a hard time figuring out if this can ever cause an information leak
(I don't think so), but nonetheless it does not hurt to increase the
robustness of the code.

Fixes: 68e03de98507 ('ALSA: hda - hdmi: Do not expose eld data when eld is invalid')
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: David Henningsson <david.henningsson@xxxxxxxxxxxxx>
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
sound/pci/hda/patch_hdmi.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
index 6a7fdab..705e6c1 100644
--- a/sound/pci/hda/patch_hdmi.c
+++ b/sound/pci/hda/patch_hdmi.c
@@ -435,7 +435,8 @@ static int hdmi_eld_ctl_get(struct snd_kcontrol *kcontrol,
eld = &per_pin->sink_eld;

- if (eld->eld_size > ARRAY_SIZE(ucontrol->value.bytes.data)) {
+ if (eld->eld_size > ARRAY_SIZE(ucontrol->value.bytes.data) ||
+ eld->eld_size > ELD_MAX_SIZE) {
return -EINVAL;