From 2e288333e9e0a14f9895321a848992b25a0e5563 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Amadeusz=20S=C5=82awi=C5=84ski?= <amadeuszx.slawinski@linux.intel.com>
Date: Fri, 15 Oct 2021 18:12:54 +0200
Subject: [PATCH] ASoC: topology: Check for dapm widget completeness
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Git-commit: 2e288333e9e0a14f9895321a848992b25a0e5563
Patch-mainline: v5.16-rc1
References: jsc#PED-850

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>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 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 e5352cc6524f..f03f50653eca 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",
-- 
2.35.3