CVE-2023-53095

Summary

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

drm/ttm: Fix a NULL pointer dereference

The LRU mechanism may look up a resource in the process of being removed from an object. The locking rules here are a bit unclear but it looks currently like res->bo assignment is protected by the LRU lock, whereas bo->resource is protected by the object lock, while clearing of bo->resource is also protected by the LRU lock. This means that if we check that bo->resource points to the LRU resource under the LRU lock we should be safe. So perform that check before deciding to swap out a bo. That avoids dereferencing a NULL bo->resource in ttm_bo_swapout().

Affected Software

VendorProductVersion RangeStatus
LinuxLinux6a9b028994025f5033f10d1da30b29dfdc713384 < 9ba1720f6c4a0f13c3f3cb5c28132ee75555d04faffected
LinuxLinux6a9b028994025f5033f10d1da30b29dfdc713384 < 9d9b1f9f7a72d83ebf173534e76b246349f32374affected
LinuxLinux6a9b028994025f5033f10d1da30b29dfdc713384 < 9a9a8fe26751334b7739193a94eba741073b8a55affected
LinuxLinux5.19affected
LinuxLinux0 < 5.19unaffected
LinuxLinux6.1.21 <= 6.1.*unaffected
LinuxLinux6.2.8 <= 6.2.*unaffected
LinuxLinux6.3 <= *unaffected

Weaknesses

References