Linux vulnerability

What happened

In the Linux kernel, the following vulnerability has been resolved: rust: devres: fix race between concurrent revokers There is a potential race condition when two paths try to revoke a Devres concurrently. The driver core's devres_release_all() calls Revocable::revoke() via the release callback, while Devres::drop() calls revoke_nosync() on another CPU. The revoker that does not claim the is_available swap returns immediately, but the revoker that did may still be executing drop_in_place() on the inner data. This can cause a use-after-free when the other revoker's caller proceeds to drop adjacent resources that drop_in_place() still references (e.g., Devres<DmaMappedSgt> racing with SGTable freeing the backing sg_table and pages). Fix this by adding a Completion. The release callback signals the Completion after revoke() finishes, and Devres::drop() waits for it when it loses the is_available swap. This ensures the wrapped object is fully torn down before Devres::drop() returns.

Affected versions

Linux: 05aa6fb1c21d7fb9df735da24096d793223789d5 through before e7930d857cc7930fc39b487ea9f3a453eca3713e (git); 05aa6fb1c21d7fb9df735da24096d793223789d5 through before c7e3d57c705ab1053a6a1bbef96795e792da1540 (git); 05aa6fb1c21d7fb9df735da24096d793223789d5 through before acc516dfa1972d31836b50abc0115216cd0fccc5 (git); 6.18 Fixed: See vendor advisory.

Why it matters

Review the vendor advisory and exposure of the affected product to determine operational impact.

Detection & mitigation

• Apply vendor-provided updates or mitigations.
• Review affected product exposure and access logs.