Smatch complains about "head->full_size - head->header_size" can
underflow. To some extent, we're always going to have to trust the
firmware a bit. However, it's easy enough to add a check for negatives,
and let's add a upper bounds check as well.
Fixes: d2458baa799f ("ASoC: SOF: ipc3-loader: Implement firmware parsing and loading")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
sound/soc/sof/ipc3-loader.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/sound/soc/sof/ipc3-loader.c b/sound/soc/sof/ipc3-loader.c
index 28218766d211..6e3ef0672110 100644
--- a/sound/soc/sof/ipc3-loader.c
+++ b/sound/soc/sof/ipc3-loader.c
@@ -148,6 +148,8 @@ static size_t sof_ipc3_fw_parse_ext_man(struct snd_sof_dev *sdev)
head = (struct sof_ext_man_header *)fw->data;
remaining = head->full_size - head->header_size;
+ if (remaining < 0 || remaining > sdev->basefw.fw->size)
+ return -EINVAL;
ext_man_size = ipc3_fw_ext_man_size(sdev, fw);
/* Assert firmware starts with extended manifest */
--
2.43.0
