CVE-2021-47604 Information

Description

In the Linux kernel the following vulnerability has been resolved:

vduse: check that offset is within bounds in get_config()

This condition checks \len\ but it does not check \offset\ and that could result in an out of bounds read if \offset > dev->config_size. The problem is that since both variables are unsigned the \dev->config_size - offset\ subtraction would result in a very high unsigned value.

I think these checks might not be necessary because \len\ and \offset\nare supposed to already have been validated using the vhost_vdpa_config_validate() function. But I do not know the code perfectly and I like to be safe.

Reference

https://git.kernel.org/stable/c/ebbbc5fea3f648175df1aa3f127c78eb0252cc2a https://git.kernel.org/stable/c/dc1db0060c02d119fd4196924eff2d1129e9a442