This is a note to let you know that I've just added the patch titled netfilter: nf_tables: reject table flag and netdev basechain updates to the 6.8-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: netfilter-nf_tables-reject-table-flag-and-netdev-bas.patch and it can be found in the queue-6.8 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 24c3a7d923529a5cb7754cedc7c94e8ab519bf09 Author: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> Date: Thu Mar 21 01:27:59 2024 +0100 netfilter: nf_tables: reject table flag and netdev basechain updates [ Upstream commit 1e1fb6f00f52812277963365d9bd835b9b0ea4e0 ] netdev basechain updates are stored in the transaction object hook list. When setting on the table dormant flag, it iterates over the existing hooks in the basechain. Thus, skipping the hooks that are being added/deleted in this transaction, which leaves hook registration in inconsistent state. Reject table flag updates in combination with netdev basechain updates in the same batch: - Update table flags and add/delete basechain: Check from basechain update path if there are pending flag updates for this table. - add/delete basechain and update table flags: Iterate over the transaction list to search for basechain updates from the table update path. In both cases, the batch is rejected. Based on suggestion from Florian Westphal. Fixes: b9703ed44ffb ("netfilter: nf_tables: support for adding new devices to an existing netdev chain") Fixes: 7d937b107108f ("netfilter: nf_tables: support for deleting devices in an existing netdev chain") Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index 00288b31f734c..db233965631bb 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -1198,6 +1198,25 @@ static void nf_tables_table_disable(struct net *net, struct nft_table *table) #define __NFT_TABLE_F_UPDATE (__NFT_TABLE_F_WAS_DORMANT | \ __NFT_TABLE_F_WAS_AWAKEN) +static bool nft_table_pending_update(const struct nft_ctx *ctx) +{ + struct nftables_pernet *nft_net = nft_pernet(ctx->net); + struct nft_trans *trans; + + if (ctx->table->flags & __NFT_TABLE_F_UPDATE) + return true; + + list_for_each_entry(trans, &nft_net->commit_list, list) { + if ((trans->msg_type == NFT_MSG_NEWCHAIN || + trans->msg_type == NFT_MSG_DELCHAIN) && + trans->ctx.table == ctx->table && + nft_trans_chain_update(trans)) + return true; + } + + return false; +} + static int nf_tables_updtable(struct nft_ctx *ctx) { struct nft_trans *trans; @@ -1221,7 +1240,7 @@ static int nf_tables_updtable(struct nft_ctx *ctx) return -EOPNOTSUPP; /* No dormant off/on/off/on games in single transaction */ - if (ctx->table->flags & __NFT_TABLE_F_UPDATE) + if (nft_table_pending_update(ctx)) return -EINVAL; trans = nft_trans_alloc(ctx, NFT_MSG_NEWTABLE, @@ -2619,6 +2638,13 @@ static int nf_tables_updchain(struct nft_ctx *ctx, u8 genmask, u8 policy, } } + if (table->flags & __NFT_TABLE_F_UPDATE && + !list_empty(&hook.list)) { + NL_SET_BAD_ATTR(extack, attr); + err = -EOPNOTSUPP; + goto err_hooks; + } + if (!(table->flags & NFT_TABLE_F_DORMANT) && nft_is_base_chain(chain) && !list_empty(&hook.list)) { @@ -2848,6 +2874,9 @@ static int nft_delchain_hook(struct nft_ctx *ctx, struct nft_trans *trans; int err; + if (ctx->table->flags & __NFT_TABLE_F_UPDATE) + return -EOPNOTSUPP; + err = nft_chain_parse_hook(ctx->net, basechain, nla, &chain_hook, ctx->family, chain->flags, extack); if (err < 0)