[PATCH 3/6] ASoC: topology: Check for dapm widget completeness

[Cezary Rojewski]

From: Amadeusz Sławiński <amadeuszx.slawinski at linux.intel.com>

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 at linux.intel.com>
Signed-off-by: Cezary Rojewski <cezary.rojewski at intel.com>
---
 sound/soc/soc-topology.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/sound/soc/soc-topology.c b/sound/soc/soc-topology.c
index 2484de8fd79a..5b73e1455c23 100644
--- 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",
-- 
2.25.1