[PATCH net-next 4/6] net: rtnetlink: take instance lock inside rtnl_configure_link
From: Stanislav Fomichev <hidden>
Date: 2026-06-30 18:21:37
Subsystem:
networking [general], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
rtnl_configure_link calls __dev_change_flags() and __dev_notify_flags, both need the instance lock. rtnl_newlink_create grabs it but stacked devices do not. Move the lock inside rtnl_configure_link. Signed-off-by: Stanislav Fomichev <sdf@fomichev.me> --- net/core/rtnetlink.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-)
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 12aa3aa1688b..1b7d6f6b8b68 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c@@ -3660,14 +3660,16 @@ int rtnl_configure_link(struct net_device *dev, const struct ifinfomsg *ifm, u32 portid, const struct nlmsghdr *nlh) { unsigned int old_flags, changed; - int err; + int err = 0; + + netdev_lock_ops(dev); old_flags = dev->flags; if (ifm && (ifm->ifi_flags || ifm->ifi_change)) { err = __dev_change_flags(dev, rtnl_dev_combine_flags(dev, ifm), NULL); if (err < 0) - return err; + goto out; } changed = old_flags ^ dev->flags;
@@ -3677,7 +3679,10 @@ int rtnl_configure_link(struct net_device *dev, const struct ifinfomsg *ifm, } __dev_notify_flags(dev, old_flags, changed, portid, nlh); - return 0; + +out: + netdev_unlock_ops(dev); + return err; } EXPORT_SYMBOL(rtnl_configure_link);
@@ -3918,22 +3923,20 @@ static int rtnl_newlink_create(struct sk_buff *skb, struct ifinfomsg *ifm, goto out; } - netdev_lock_ops(dev); - err = rtnl_configure_link(dev, ifm, portid, nlh); if (err < 0) goto out_unregister; if (tb[IFLA_MASTER]) { + netdev_lock_ops(dev); err = do_set_master(dev, nla_get_u32(tb[IFLA_MASTER]), extack); + netdev_unlock_ops(dev); if (err) goto out_unregister; } - netdev_unlock_ops(dev); out: return err; out_unregister: - netdev_unlock_ops(dev); if (ops->newlink) { LIST_HEAD(list_kill);
--
2.53.0-Meta