netdev basechain updates are stored in the transaction object hook list. Meanwhile, updates in the table dormant flags iterate 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 flags 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> --- net/netfilter/nf_tables_api.c | 31 ++++++++++++++++++++++++++++++- 1 file changed, 30 insertions(+), 1 deletion(-) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index a1a8030e16a5..086d85fffeb1 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -1200,6 +1200,25 @@ static void nf_tables_table_disable(struct net *net, struct nft_table *table) __NFT_TABLE_F_WAS_AWAKEN | \ __NFT_TABLE_F_WAS_ORPHAN) +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; @@ -1226,7 +1245,7 @@ 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, @@ -2631,6 +2650,13 @@ 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)) { @@ -2860,6 +2886,9 @@ 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) -- 2.30.2