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 <pablo@netfilter.org>
This commit is contained in:
Pablo Neira Ayuso 2017-09-03 23:56:00 +02:00
parent 2335ba704f
commit a827840080

View File

@ -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);