netfilter: nf_tables: don't update chain with unset counters

Fix possible replacement of the per-cpu chain counters by null
pointer when updating an existing chain in the commit path.

Reported-by: Matteo Croce <technoboy85@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Pablo Neira Ayuso 2014-08-05 17:25:59 +02:00
parent a3716e70e1
commit b88825de85
1 changed files with 3 additions and 0 deletions

View File

@ -899,6 +899,9 @@ static struct nft_stats __percpu *nft_stats_alloc(const struct nlattr *attr)
static void nft_chain_stats_replace(struct nft_base_chain *chain,
struct nft_stats __percpu *newstats)
{
if (newstats == NULL)
return;
if (chain->stats) {
struct nft_stats __percpu *oldstats =
nft_dereference(chain->stats);