In the Linux kernel, a vulnerability has been identified and resolved in the "media: nxp: imx8-isi" subsystem. This subsystem deals with the translation of source to sink streams in the crossbar sub-device. The vulnerability occurs during the process of locating a remote sub-device when trying to enable a stream that ends at an unconnected crossbar sink. The issue arises when the remote pad is NULL and causes the driver to crash. This blog post discusses the details of the vulnerability, its impact, and the code update that resolves it.

Vulnerability Details

A NULL pointer dereference vulnerability existed in the Linux kernel's "media: nxp: imx8-isi" driver. This vulnerability could be exploited if userspace tried to enable a stream that ends at an unconnected crossbar sink (CVE-2023-52647). As a result, the driver would attempt to access the NULL remote pad and crash, potentially leading to denial of service issues.

The fix for this vulnerability involves checking whether the crossbar pad is non-NULL before trying to access it. If the pad is NULL, the driver will return an error instead of attempting to access it and crashing.

The following code snippet showcases the fix implemented to resolve the vulnerability

static int media_entity_remote_pad(struct media_pad *pad)
{
  ...
  if (!pad)
	return -EINVAL;

  src_entity = pad->entity;
  ...
}

- Linux kernel source repository
- Linux kernel mailing list

Exploit Details

While there are no known exploits for this specific vulnerability, it is essential to keep your Linux kernel version updated to stay protected against potential threats. Ensuring your kernel has the latest patches helps maintain system security and stability.

In Summary

The Linux kernel's "media: nxp: imx8-isi" driver had a NULL pointer dereference vulnerability, which could lead to a crash and possible denial of service issues. The vulnerability was resolved by checking whether the crossbar pad is non-NULL before accessing it. This simple fix ensures that the driver returns an error if the pad is NULL, preventing the crash and maintaining system stability. It is advisable to keep your Linux kernel updated to stay protected against this and other potential vulnerabilities.

Timeline

Published on: 05/01/2024 06:15:06 UTC
Last modified on: 05/29/2024 05:15:04 UTC