In the Linux kernel, the following vulnerability has been resolved: net: page_pool: fix use-after-free in page_pool_recycle_ring_bulk() With CONFIG_PAGE_POOL_STATS=y, page_pool_recycle_ring_bulk() updates the recycle stats after dropping the producer lock. If it just recycled the last inflight netmems of a pool being destroyed, page_pool_release() can pass its producer-lock barrier and free the pool before recycle_stat_add() runs. Commit fcc680a647ba7 ("page_pool: allow mixing PPs within one bulk") moved this stat update after the unlock. Commit 271683bb2cf32 ("page_pool: Fix use-after-free in page_pool_recycle_in_ring") later added the barrier, but only fixed page_pool_recycle_in_ring(). Move the update back under the lock.
https://git.kernel.org/stable/c/f78d45d5f1ac4141a03f033141368671da4293e4
https://git.kernel.org/stable/c/bdea4980182e3badac74f04df6c07492b91c569e
https://git.kernel.org/stable/c/0b105f4eb78e5ee39e5a74c47c9efd69b6ac849c