GeezerVison

…60196) (#160364)

On free-threaded builds, list.__sizeof__() reads an allocation header through an atomically loaded storage pointer. The list's owner can resize and free that storage between the load and the header read, producing invalid size data or an invalid memory read. Hold the list lock while inspecting the allocation. Backport to 3.15 and 3.14.
(cherry picked from commit d98f2cb)

Co-authored-by: Jelle Zijlstra <[email protected]>

…60196) (#160363)

On free-threaded builds, list.__sizeof__() reads an allocation header through an atomically loaded storage pointer. The list's owner can resize and free that storage between the load and the header read, producing invalid size data or an invalid memory read. Hold the list lock while inspecting the allocation. Backport to 3.15 and 3.14.
(cherry picked from commit d98f2cb)

Co-authored-by: Jelle Zijlstra <[email protected]>