CVE-2026-63858

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

netfilter: nf_tables: add hook transactions for device deletions

Restore the flag that indicates that the hook is going away, ie.

NFT_HOOK_REMOVE, but add a new transaction object to track deletion

of hooks without altering the basechain/flowtable hook_list during

the preparation phase.

The existing approach that moves the hook from the basechain/flowtable

hook_list to transaction hook_list breaks netlink dump path readers

of this RCU-protected list.

It should be possible use an array for nft_trans_hook to store the

deleted hooks to compact the representation but I am not expecting

many hook object, specially now that wildcard support for devices

is in place.

Note that the nft_trans_chain_hooks() list contains a list of struct

nft_trans_hook objects for DELCHAIN and DELFLOWTABLE commands, while

this list stores struct nft_hook objects for NEWCHAIN and NEWFLOWTABLE.

Note that new commands can be updated to use nft_trans_hook for

consistency.

This patch also adapts the event notification path to deal with the list

of hook transactions.