drm/nouveau: fix pramdac_table range checking

get_tmds_index_reg reads some value from stack when mlv happens
to be equal to size of pramdac_table array. Fix it.

Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Signed-off-by: Francisco Jerez <currojerez@riseup.net>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

diff --git a/drivers/gpu/drm/nouveau/nouveau_bios.c b/drivers/gpu/drm/nouveau/nouveau_bios.c
index 0e9cd1d..c1cee91 100644 (file)
--- a/drivers/gpu/drm/nouveau/nouveau_bios.c
+++ b/drivers/gpu/drm/nouveau/nouveau_bios.c
@@ -762,7 +762,7 @@ static uint32_t get_tmds_index_reg(struct drm_device *dev, uint8_t mlv)
                        dacoffset ^= 8;
                return 0x6808b0 + dacoffset;
        } else {
-               if (mlv > ARRAY_SIZE(pramdac_table)) {
+               if (mlv >= ARRAY_SIZE(pramdac_table)) {
                        NV_ERROR(dev, "Magic Lookup Value too big (%02X)\n",
                                                                        mlv);
                        return 0;