nfp: flower: fix for take a mutex lock in soft irq context and rcu lock

commit 0ad722bd9ee3a9bdfca9613148645e4c9b7f26cf upstream.

The neighbour event callback call the function nfp_tun_write_neigh,
this function will take a mutex lock and it is in soft irq context,
change the work queue to process the neighbour event.

Move the nfp_tun_write_neigh function out of range rcu_read_lock/unlock()
in function nfp_tunnel_request_route_v4 and nfp_tunnel_request_route_v6.

Fixes: abc210952af7 ("nfp: flower: tunnel neigh support bond offload")
CC: stable@vger.kernel.org # 6.2+
Signed-off-by: Hui Zhou <hui.zhou@corigine.com>
Signed-off-by: Louis Peens <louis.peens@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/ethernet/netronome/nfp/flower/tunnel_conf.c b/drivers/net/ethernet/netronome/nfp/flower/tunnel_conf.c
index 060a77f..e522845 100644 (file)
--- a/drivers/net/ethernet/netronome/nfp/flower/tunnel_conf.c
+++ b/drivers/net/ethernet/netronome/nfp/flower/tunnel_conf.c
@@ -160,6 +160,18 @@ struct nfp_tun_mac_addr_offload {
        u8 addr[ETH_ALEN];
 };
 
+/**
+ * struct nfp_neigh_update_work - update neighbour information to nfp
+ * @work:      Work queue for writing neigh to the nfp
+ * @n:         neighbour entry
+ * @app:       Back pointer to app
+ */
+struct nfp_neigh_update_work {
+       struct work_struct work;
+       struct neighbour *n;
+       struct nfp_app *app;
+};
+
 enum nfp_flower_mac_offload_cmd {
        NFP_TUNNEL_MAC_OFFLOAD_ADD =            0,
        NFP_TUNNEL_MAC_OFFLOAD_DEL =            1,
@@ -607,38 +619,30 @@ err:
        nfp_flower_cmsg_warn(app, "Neighbour configuration failed.\n");
 }
 
-static int
-nfp_tun_neigh_event_handler(struct notifier_block *nb, unsigned long event,
-                           void *ptr)
+static void
+nfp_tun_release_neigh_update_work(struct nfp_neigh_update_work *update_work)
 {
-       struct nfp_flower_priv *app_priv;
-       struct netevent_redirect *redir;
-       struct neighbour *n;
+       neigh_release(update_work->n);
+       kfree(update_work);
+}
+
+static void nfp_tun_neigh_update(struct work_struct *work)
+{
+       struct nfp_neigh_update_work *update_work;
        struct nfp_app *app;
+       struct neighbour *n;
        bool neigh_invalid;
        int err;
 
-       switch (event) {
-       case NETEVENT_REDIRECT:
-               redir = (struct netevent_redirect *)ptr;
-               n = redir->neigh;
-               break;
-       case NETEVENT_NEIGH_UPDATE:
-               n = (struct neighbour *)ptr;
-               break;
-       default:
-               return NOTIFY_DONE;
-       }
-
-       neigh_invalid = !(n->nud_state & NUD_VALID) || n->dead;
-
-       app_priv = container_of(nb, struct nfp_flower_priv, tun.neigh_nb);
-       app = app_priv->app;
+       update_work = container_of(work, struct nfp_neigh_update_work, work);
+       app = update_work->app;
+       n = update_work->n;
 
        if (!nfp_flower_get_port_id_from_netdev(app, n->dev))
-               return NOTIFY_DONE;
+               goto out;
 
 #if IS_ENABLED(CONFIG_INET)
+       neigh_invalid = !(n->nud_state & NUD_VALID) || n->dead;
        if (n->tbl->family == AF_INET6) {
 #if IS_ENABLED(CONFIG_IPV6)
                struct flowi6 flow6 = {};
@@ -655,13 +659,11 @@ nfp_tun_neigh_event_handler(struct notifier_block *nb, unsigned long event,
                        dst = ip6_dst_lookup_flow(dev_net(n->dev), NULL,
                                                  &flow6, NULL);
                        if (IS_ERR(dst))
-                               return NOTIFY_DONE;
+                               goto out;
 
                        dst_release(dst);
                }
                nfp_tun_write_neigh(n->dev, app, &flow6, n, true, false);
-#else
-               return NOTIFY_DONE;
 #endif /* CONFIG_IPV6 */
        } else {
                struct flowi4 flow4 = {};
@@ -678,17 +680,71 @@ nfp_tun_neigh_event_handler(struct notifier_block *nb, unsigned long event,
                        rt = ip_route_output_key(dev_net(n->dev), &flow4);
                        err = PTR_ERR_OR_ZERO(rt);
                        if (err)
-                               return NOTIFY_DONE;
+                               goto out;
 
                        ip_rt_put(rt);
                }
                nfp_tun_write_neigh(n->dev, app, &flow4, n, false, false);
        }
-#else
-       return NOTIFY_DONE;
 #endif /* CONFIG_INET */
+out:
+       nfp_tun_release_neigh_update_work(update_work);
+}
 
-       return NOTIFY_OK;
+static struct nfp_neigh_update_work *
+nfp_tun_alloc_neigh_update_work(struct nfp_app *app, struct neighbour *n)
+{
+       struct nfp_neigh_update_work *update_work;
+
+       update_work = kzalloc(sizeof(*update_work), GFP_ATOMIC);
+       if (!update_work)
+               return NULL;
+
+       INIT_WORK(&update_work->work, nfp_tun_neigh_update);
+       neigh_hold(n);
+       update_work->n = n;
+       update_work->app = app;
+
+       return update_work;
+}
+
+static int
+nfp_tun_neigh_event_handler(struct notifier_block *nb, unsigned long event,
+                           void *ptr)
+{
+       struct nfp_neigh_update_work *update_work;
+       struct nfp_flower_priv *app_priv;
+       struct netevent_redirect *redir;
+       struct neighbour *n;
+       struct nfp_app *app;
+
+       switch (event) {
+       case NETEVENT_REDIRECT:
+               redir = (struct netevent_redirect *)ptr;
+               n = redir->neigh;
+               break;
+       case NETEVENT_NEIGH_UPDATE:
+               n = (struct neighbour *)ptr;
+               break;
+       default:
+               return NOTIFY_DONE;
+       }
+#if IS_ENABLED(CONFIG_IPV6)
+       if (n->tbl != ipv6_stub->nd_tbl && n->tbl != &arp_tbl)
+#else
+       if (n->tbl != &arp_tbl)
+#endif
+               return NOTIFY_DONE;
+
+       app_priv = container_of(nb, struct nfp_flower_priv, tun.neigh_nb);
+       app = app_priv->app;
+       update_work = nfp_tun_alloc_neigh_update_work(app, n);
+       if (!update_work)
+               return NOTIFY_DONE;
+
+       queue_work(system_highpri_wq, &update_work->work);
+
+       return NOTIFY_DONE;
 }
 
 void nfp_tunnel_request_route_v4(struct nfp_app *app, struct sk_buff *skb)
@@ -706,6 +762,7 @@ void nfp_tunnel_request_route_v4(struct nfp_app *app, struct sk_buff *skb)
        netdev = nfp_app_dev_get(app, be32_to_cpu(payload->ingress_port), NULL);
        if (!netdev)
                goto fail_rcu_unlock;
+       dev_hold(netdev);
 
        flow.daddr = payload->ipv4_addr;
        flow.flowi4_proto = IPPROTO_UDP;
@@ -725,13 +782,16 @@ void nfp_tunnel_request_route_v4(struct nfp_app *app, struct sk_buff *skb)
        ip_rt_put(rt);
        if (!n)
                goto fail_rcu_unlock;
+       rcu_read_unlock();
+
        nfp_tun_write_neigh(n->dev, app, &flow, n, false, true);
        neigh_release(n);
-       rcu_read_unlock();
+       dev_put(netdev);
        return;
 
 fail_rcu_unlock:
        rcu_read_unlock();
+       dev_put(netdev);
        nfp_flower_cmsg_warn(app, "Requested route not found.\n");
 }
 
@@ -749,6 +809,7 @@ void nfp_tunnel_request_route_v6(struct nfp_app *app, struct sk_buff *skb)
        netdev = nfp_app_dev_get(app, be32_to_cpu(payload->ingress_port), NULL);
        if (!netdev)
                goto fail_rcu_unlock;
+       dev_hold(netdev);
 
        flow.daddr = payload->ipv6_addr;
        flow.flowi6_proto = IPPROTO_UDP;
@@ -766,14 +827,16 @@ void nfp_tunnel_request_route_v6(struct nfp_app *app, struct sk_buff *skb)
        dst_release(dst);
        if (!n)
                goto fail_rcu_unlock;
+       rcu_read_unlock();
 
        nfp_tun_write_neigh(n->dev, app, &flow, n, true, true);
        neigh_release(n);
-       rcu_read_unlock();
+       dev_put(netdev);
        return;
 
 fail_rcu_unlock:
        rcu_read_unlock();
+       dev_put(netdev);
        nfp_flower_cmsg_warn(app, "Requested IPv6 route not found.\n");
 }