[PATCH 3.16.y-ckt 095/129] ALSA: hda - Fix static checker warning in patch_hdmi.c

From: Luis Henriques
Date: Fri Feb 26 2016 - 05:43:50 EST

3.16.7-ckt25 -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: Luis Henriques <luis.henriques@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 31a80b10c783..e063a4a7e881 100644
--- a/sound/pci/hda/patch_hdmi.c
+++ b/sound/pci/hda/patch_hdmi.c
@@ -430,7 +430,8 @@ 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;