CVE-2023-52913: drm/i915: Fix potential context UAFs

Description

In the Linux kernel, the following vulnerability has been resolved:

drm/i915: Fix potential context UAFs

gem_context_register() makes the context visible to userspace, and which
point a separate thread can trigger the I915_GEM_CONTEXT_DESTROY ioctl.
So we need to ensure that nothing uses the ctx ptr after this. And we
need to ensure that adding the ctx to the xarray is the *last* thing
that gem_context_register() does with the ctx pointer.

[tursulin: Stable and fixes tags add/tidy.]
(cherry picked from commit bed4b455cf5374e68879be56971c1da563bcd90c)

Classification

CVE ID: CVE-2023-52913

Affected Products

Vendor: Linux

Product: Linux

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.04% (probability of being exploited)

EPSS Percentile: 5.08% (scored less or equal to compared to others)

EPSS Date: 2025-02-04 (when was this score calculated)

References

https://git.kernel.org/stable/c/ae278887193110dfeb857ea63e243a3851fbb0bc
https://git.kernel.org/stable/c/b696c627b3f56e173f7f70b8487d66da8ff22506
https://git.kernel.org/stable/c/afce71ff6daa9c0f852df0727fe32c6fb107f0fa

Timeline