From a8278400809dd99eb24468c02c8d4f0cb0003eae Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Sun, 3 Sep 2017 23:56:00 +0200 Subject: [PATCH] netfilter: nf_tables: use NLM_F_NONREC for deletion requests Bail out if user requests non-recursive deletion for tables and sets. This new flags tells nf_tables netlink interface to reject deletions if tables and sets have content. Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_tables_api.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index d95dfafea1e7..47fc7cd3f936 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -860,6 +860,10 @@ static int nf_tables_deltable(struct net *net, struct sock *nlsk, if (IS_ERR(table)) return PTR_ERR(table); + if (nlh->nlmsg_flags & NLM_F_NONREC && + table->use > 0) + return -EBUSY; + ctx.afi = afi; ctx.table = table; @@ -3225,7 +3229,9 @@ static int nf_tables_delset(struct net *net, struct sock *nlsk, set = nf_tables_set_lookup(ctx.table, nla[NFTA_SET_NAME], genmask); if (IS_ERR(set)) return PTR_ERR(set); - if (!list_empty(&set->bindings)) + + if (!list_empty(&set->bindings) || + (nlh->nlmsg_flags & NLM_F_NONREC && atomic_read(&set->nelems) > 0)) return -EBUSY; return nft_delset(&ctx, set);