CVE-2023-52930

A flaw was found in the Linux kernel's Intel graphics driver (i915), specifically within the Direct Rendering Manager (DRM) subsystem. This issue arises when multiple threads simultaneously attempt to set the tiling mode of a graphics buffer to I915_TILING_NONE using the I915_GEM_SET_TILING ioctl. These concurrent operations can lead to a race condition, resulting in a double-free of the bit_17 bitmask or a memory leak during the transition to a tiled mode. The root cause is the lack of proper synchronization when allocating and freeing the bitmask, leading to potential memory corruption and system instability.

The vulnerability occurs in the i915 driver when using the DRM_IOCTL_I915_GEM_SET_TILING ioctl, which is only accessible to processes with sufficient privileges to open /dev/dri/* (the DRM device). Access to this device node is not granted to unprivileged users by default on most systems.

Exploiting this vulnerability typically requires elevated privileges unless one of the following occurs:

• The system is configured to allow unprivileged users to access the DRM device node (for example, through udev rules or group membership like video),
• Or the process is already running with elevated privileges (for example, root).

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.