CVE-2021-47604: vduse: check that offset is within bounds in get_config()

Vulnerability summary

CVE-2021-47604 is a high (CVSS 7.1) Out-of-bounds Read vulnerability in linux. EPSS estimates a 0.21% chance of exploitation in the next 30 days, higher than 11.3% of scored vulnerabilities.

Timeline

1. 19-06-2024
   PublishedVulnerability first disclosed.
2. 05-08-2026
   Last modifiedVulnerability information updated.

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" are 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.

• CWE-125Out-of-bounds ReadThe product reads data past the end, or before the beginning, of the intended buffer.