[PATCH v2 net 1/3] gtp: Use for_each_netdev_rcu() in gtp_genl_dump_pdp().
From: Kuniyuki Iwashima <hidden>
Date: 2025-01-10 01:48:39
Subsystem:
gtp (gprs tunneling protocol), networking drivers, the rest · Maintainers:
Pablo Neira Ayuso, Harald Welte, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
gtp_newlink() links the gtp device to a list in dev_net(dev).
However, even after the gtp device is moved to another netns,
it stays on the list but should be invisible.
Let's use for_each_netdev_rcu() for netdev traversal in
gtp_genl_dump_pdp().
Note that gtp_dev_list is no longer used under RCU, so list
helpers are converted to the non-RCU variant.
Fixes: 459aa660eb1d ("gtp: add initial driver for datapath of GPRS Tunneling Protocol (GTP-U)")
Reported-by: Xiao Liang <redacted>
Closes: https://lore.kernel.org/netdev/CABAhCOQdBL6h9M2C+kd+bGivRJ9Q72JUxW+-gur0nub_=PmFPA@mail.gmail.com/ (local)
Signed-off-by: Kuniyuki Iwashima <redacted>
---
v2:
* Fix uninit variable (gtp) and remove unused var (gn) in gtp_genl_dump_pdp().
v1: https://lore.kernel.org/netdev/20250108062834.11117-2-kuniyu@amazon.com/ (local)
---
drivers/net/gtp.c | 19 +++++++++++--------
1 file changed, 11 insertions(+), 8 deletions(-)
diff --git a/drivers/net/gtp.c b/drivers/net/gtp.c
index 89a996ad8cd0..0f9cb0c378af 100644
--- a/drivers/net/gtp.c
+++ b/drivers/net/gtp.c@@ -1525,7 +1525,7 @@ static int gtp_newlink(struct net *src_net, struct net_device *dev, } gn = net_generic(dev_net(dev), gtp_net_id); - list_add_rcu(>p->list, &gn->gtp_dev_list); + list_add(>p->list, &gn->gtp_dev_list); dev->priv_destructor = gtp_destructor; netdev_dbg(dev, "registered new GTP interface\n");
@@ -1551,7 +1551,7 @@ static void gtp_dellink(struct net_device *dev, struct list_head *head) hlist_for_each_entry_safe(pctx, next, >p->tid_hash[i], hlist_tid) pdp_context_delete(pctx); - list_del_rcu(>p->list); + list_del(>p->list); unregister_netdevice_queue(dev, head); }
@@ -2271,16 +2271,19 @@ static int gtp_genl_dump_pdp(struct sk_buff *skb, struct gtp_dev *last_gtp = (struct gtp_dev *)cb->args[2], *gtp; int i, j, bucket = cb->args[0], skip = cb->args[1]; struct net *net = sock_net(skb->sk); + struct net_device *dev; struct pdp_ctx *pctx; - struct gtp_net *gn; - - gn = net_generic(net, gtp_net_id); if (cb->args[4]) return 0; rcu_read_lock(); - list_for_each_entry_rcu(gtp, &gn->gtp_dev_list, list) { + for_each_netdev_rcu(net, dev) { + if (dev->rtnl_link_ops != >p_link_ops) + continue; + + gtp = netdev_priv(dev); + if (last_gtp && last_gtp != gtp) continue; else
@@ -2475,9 +2478,9 @@ static void __net_exit gtp_net_exit_batch_rtnl(struct list_head *net_list, list_for_each_entry(net, net_list, exit_list) { struct gtp_net *gn = net_generic(net, gtp_net_id); - struct gtp_dev *gtp; + struct gtp_dev *gtp, *gtp_next; - list_for_each_entry(gtp, &gn->gtp_dev_list, list) + list_for_each_entry_safe(gtp, gtp_next, &gn->gtp_dev_list, list) gtp_dellink(gtp->dev, dev_to_kill); } }
--
2.39.5 (Apple Git-154)