From 9cc0001a18b4e5f46ec481201c88ae16f0a69bb0 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Sat, 27 Feb 2021 22:31:27 +0100 Subject: netfilter: nftables: disallow updates on table ownership Disallow updating the ownership bit on an existing table: Do not allow to grab ownership on an existing table. Do not allow to drop ownership on an existing table. Fixes: 6001a930ce03 ("netfilter: nftables: introduce table ownership") Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_tables_api.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'net') diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index c1eb5cdb3033..b07703e19108 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -916,6 +916,12 @@ static int nf_tables_updtable(struct nft_ctx *ctx) if (flags == ctx->table->flags) return 0; + if ((nft_table_has_owner(ctx->table) && + !(flags & NFT_TABLE_F_OWNER)) || + (!nft_table_has_owner(ctx->table) && + flags & NFT_TABLE_F_OWNER)) + return -EOPNOTSUPP; + trans = nft_trans_alloc(ctx, NFT_MSG_NEWTABLE, sizeof(struct nft_trans_table)); if (trans == NULL) -- cgit v1.2.3