netfilter: nft_synproxy: avoid possible data-race on update operation

During nft_synproxy eval we are reading nf_synproxy_info struct which
can be modified on update operation concurrently. As nf_synproxy_info
struct fits in 32 bits, use READ_ONCE/WRITE_ONCE annotations.

Fixes: ee394f96ad ("netfilter: nft_synproxy: add synproxy stateful object support")
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Signed-off-by: Florian Westphal <fw@strlen.de>
This commit is contained in:
Fernando Fernandez Mancera
2025-12-17 21:21:59 +01:00
committed by Florian Westphal
parent a675d1caa2
commit 36a3200575

View File

@@ -48,7 +48,7 @@ static void nft_synproxy_eval_v4(const struct nft_synproxy *priv,
struct tcphdr *_tcph,
struct synproxy_options *opts)
{
struct nf_synproxy_info info = priv->info;
struct nf_synproxy_info info = READ_ONCE(priv->info);
struct net *net = nft_net(pkt);
struct synproxy_net *snet = synproxy_pernet(net);
struct sk_buff *skb = pkt->skb;
@@ -79,7 +79,7 @@ static void nft_synproxy_eval_v6(const struct nft_synproxy *priv,
struct tcphdr *_tcph,
struct synproxy_options *opts)
{
struct nf_synproxy_info info = priv->info;
struct nf_synproxy_info info = READ_ONCE(priv->info);
struct net *net = nft_net(pkt);
struct synproxy_net *snet = synproxy_pernet(net);
struct sk_buff *skb = pkt->skb;
@@ -340,7 +340,7 @@ static void nft_synproxy_obj_update(struct nft_object *obj,
struct nft_synproxy *newpriv = nft_obj_data(newobj);
struct nft_synproxy *priv = nft_obj_data(obj);
priv->info = newpriv->info;
WRITE_ONCE(priv->info, newpriv->info);
}
static struct nft_object_type nft_synproxy_obj_type;