| Message ID | 20240307021545.149386-5-pablo@netfilter.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 552705a3650bbf46a22b1adedc1b04181490fc36 |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net,1/5] netfilter: nf_tables: disallow anonymous set with timeout flag | expand |
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index fb07455143a5..1683dc196b59 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -5430,6 +5430,7 @@ static void nf_tables_unbind_set(const struct nft_ctx *ctx, struct nft_set *set, if (list_empty(&set->bindings) && nft_set_is_anonymous(set)) { list_del_rcu(&set->list); + set->dead = 1; if (event) nf_tables_set_notify(ctx, set, NFT_MSG_DELSET, GFP_KERNEL);
While the rhashtable set gc runs asynchronously, a race allows it to collect elements from anonymous sets with timeouts while it is being released from the commit path. Mingi Cho originally reported this issue in a different path in 6.1.x with a pipapo set with low timeouts which is not possible upstream since 7395dfacfff6 ("netfilter: nf_tables: use timestamp to check for set element timeout"). Fix this by setting on the dead flag for anonymous sets to skip async gc in this case. According to 08e4c8c5919f ("netfilter: nf_tables: mark newset as dead on transaction abort"), Florian plans to accelerate abort path by releasing objects via workqueue, therefore, this sets on the dead flag for abort path too. Cc: stable@vger.kernel.org Fixes: 5f68718b34a5 ("netfilter: nf_tables: GC transaction API to avoid race with control plane") Reported-by: Mingi Cho <mgcho.minic@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> --- net/netfilter/nf_tables_api.c | 1 + 1 file changed, 1 insertion(+)