In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: don't fail inserts if duplicate has expired nftables selftests fail: run-tests.sh testcases/sets/0044interval_overlap_0 Expected: 0-2 . 0-3, got: W: [FAILED] ./testcases/sets/0044interval_overlap_0: got 1 Insertion must ignore duplicate but expired entries. Moreover, there is a strange asymmetry in nft_pipapo_activate: It refetches the current element, whereas the other ->activate callbacks (bitmap, hash, rhash, rbtree) use elem->priv. Same for .remove: other set implementations take elem->priv, nft_pipapo_remove fetches elem->priv, then does a relookup, remove this. I suspect this was the reason for the change that prompted the removal of the expired check in pipapo_get() in the first place