Commit a6134e62 authored by Pablo Neira Ayuso's avatar Pablo Neira Ayuso
Browse files

netfilter: nf_tables: join hook list via splice_list_rcu() in commit phase 



Publish new hooks in the list into the basechain/flowtable using
splice_list_rcu() to ensure netlink dump list traversal via rcu is safe
while concurrent ruleset update is going on.

Fixes: 78d9f48f ("netfilter: nf_tables: add devices to existing flowtable")
Fixes: b9703ed4 ("netfilter: nf_tables: support for adding new devices to an existing netdev chain")
Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
parent f902877b

net/netfilter/nf_tables_api.c

+4 −4
Original line number Diff line number Diff line
@@ -10838,7 +10838,7 @@ static int nf_tables_commit(struct net *net, struct sk_buff *skb) 
				nft_chain_commit_update(nft_trans_container_chain(trans));

				nf_tables_chain_notify(&ctx, NFT_MSG_NEWCHAIN,

						       &nft_trans_chain_hooks(trans));

				list_splice(&nft_trans_chain_hooks(trans),

				list_splice_rcu(&nft_trans_chain_hooks(trans),

						&nft_trans_basechain(trans)->hook_list);

				/* trans destroyed after rcu grace period */

			} else {
@@ -10968,7 +10968,7 @@ static int nf_tables_commit(struct net *net, struct sk_buff *skb) 
							   nft_trans_flowtable(trans),

							   &nft_trans_flowtable_hooks(trans),

							   NFT_MSG_NEWFLOWTABLE);

				list_splice(&nft_trans_flowtable_hooks(trans),

				list_splice_rcu(&nft_trans_flowtable_hooks(trans),

						&nft_trans_flowtable(trans)->hook_list);

			} else {

				nft_clear(net, nft_trans_flowtable(trans));