ASoC: topology: Check for dapm widget completeness

Add sanity checks to make sure the data is read within file boundary.
Helps in situations where file is only partially copied or malformed.

Signed-off-by: Amadeusz Sławiński <amadeuszx.slawinski@linux.intel.com>
Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com>
Link: https://lore.kernel.org/r/20211015161257.27052-4-cezary.rojewski@intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/soc-topology.c b/sound/soc/soc-topology.c
index e5352cc..f03f506 100644 (file)
--- a/sound/soc/soc-topology.c
+++ b/sound/soc/soc-topology.c
@@ -1591,11 +1591,28 @@ static int soc_tplg_dapm_widget_elems_load(struct soc_tplg *tplg,
                struct snd_soc_tplg_dapm_widget *widget = (struct snd_soc_tplg_dapm_widget *) tplg->pos;
                int ret;
 
+               /*
+                * check if widget itself fits within topology file
+                * use sizeof instead of widget->size, as we can't be sure
+                * it is set properly yet (file may end before it is present)
+                */
+               if (soc_tplg_get_offset(tplg) + sizeof(*widget) >= tplg->fw->size) {
+                       dev_err(tplg->dev, "ASoC: invalid widget data size\n");
+                       return -EINVAL;
+               }
+
+               /* check if widget has proper size */
                if (le32_to_cpu(widget->size) != sizeof(*widget)) {
                        dev_err(tplg->dev, "ASoC: invalid widget size\n");
                        return -EINVAL;
                }
 
+               /* check if widget private data fits within topology file */
+               if (soc_tplg_get_offset(tplg) + le32_to_cpu(widget->priv.size) >= tplg->fw->size) {
+                       dev_err(tplg->dev, "ASoC: invalid widget private data size\n");
+                       return -EINVAL;
+               }
+
                ret = soc_tplg_dapm_widget_create(tplg, widget);
                if (ret < 0) {
                        dev_err(tplg->dev, "ASoC: failed to load widget %s\n",