Executive brief
The Linux kernel's Direct Rendering Manager (DRM) TTM (Translation Table Maps) memory manager had a resource leak bug in the buffer object eviction code. When certain eviction errors occurred, allocated GPU memory resources were not properly freed, causing memory to become unavailable for reuse. This could degrade system performance or lead to out-of-memory conditions on systems with dedicated graphics hardware.
Technical details
The vulnerability is a resource leak in the TTM buffer object eviction path (drivers/gpu/drm/ttm/ttm_bo.c). When ttm_bo_handle_move_mem() failed with errors other than -EMULTIHOP, the associated evict_mem resource was not freed before the function returned, causing memory to leak. The fix replaces a goto-based loop with a do-while structure to ensure ttm_resource_free() is called on all error paths. The vulnerable code was introduced in v5.15+ and affected the kernel's ability to properly manage GPU memory during device resets or memory pressure scenarios. A patch is available in stable kernel versions.
Affected products
- Linux Linux kernel v5.15 and later
Timeline
- 2023-06-26: disclosed: Patch authored by Thomas Hellström
- 2023-07-23: patched: Fix included in stable kernel releases
- 2025-12-30: advisory: CVE-2023-54254 published