[PATCH net-next v3 3/5] macsec: move netdev_upper_dev_link() after macsec_changelink_common()
From: Hangbin Liu <hidden>
Date: 2026-03-16 04:27:30
Also in:
bridge, lkml
Subsystem:
networking drivers, networking [macsec], the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Sabrina Dubroca, Linus Torvalds
After calling netdev_change_features() in __netdev_upper_dev_link(),
the call stack looks like:
- netdev_upper_dev_link
- __netdev_upper_dev_link
- netdev_change_features
- notifier_call_chain
- rtnetlink_event
- rtmsg_ifinfo_event
- rtmsg_ifinfo_build_skb
In macsec, we call netdev_upper_dev_link() before
macsec_changelink_common(), which causes the fields of the MACsec
Security Entity to be uninitialized. Later, macsec_fill_info() returns
-EMSGSIZE and triggers WARN_ON() in rtmsg_ifinfo_build_skb.
Fix this by moving netdev_upper_dev_link() after
macsec_changelink_common(), and return 0 if secy->key_len is not
initialized yet.
Suggested-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Hangbin Liu <redacted>
---
drivers/net/macsec.c | 23 ++++++++++++-----------
1 file changed, 12 insertions(+), 11 deletions(-)
diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c
index f6cad0746a02..6bb38084bc1e 100644
--- a/drivers/net/macsec.c
+++ b/drivers/net/macsec.c@@ -4161,10 +4161,6 @@ static int macsec_newlink(struct net_device *dev, lockdep_set_class(&dev->addr_list_lock, &macsec_netdev_addr_lock_key); - err = netdev_upper_dev_link(real_dev, dev, extack); - if (err < 0) - goto unregister; - /* need to be already registered so that ->init has run and * the MAC addr is set */
@@ -4177,12 +4173,12 @@ static int macsec_newlink(struct net_device *dev, if (rx_handler && sci_exists(real_dev, sci)) { err = -EBUSY; - goto unlink; + goto unregister; } err = macsec_add_dev(dev, sci, icv_len); if (err) - goto unlink; + goto unregister; if (data) { err = macsec_changelink_common(dev, data);
@@ -4190,6 +4186,10 @@ static int macsec_newlink(struct net_device *dev, goto del_dev; } + err = netdev_upper_dev_link(real_dev, dev, extack); + if (err < 0) + goto del_dev; + /* If h/w offloading is available, propagate to the device */ if (macsec_is_offloaded(macsec)) { const struct macsec_ops *ops;
@@ -4200,7 +4200,7 @@ static int macsec_newlink(struct net_device *dev, ctx.secy = &macsec->secy; err = macsec_offload(ops->mdo_add_secy, &ctx); if (err) - goto del_dev; + goto unlink; macsec->insert_tx_tag = macsec_needs_tx_tag(macsec, ops);
@@ -4209,7 +4209,7 @@ static int macsec_newlink(struct net_device *dev, err = register_macsec_dev(real_dev, dev); if (err < 0) - goto del_dev; + goto unlink; netdev_update_features(dev); netif_stacked_transfer_operstate(real_dev, dev);
@@ -4219,10 +4219,10 @@ static int macsec_newlink(struct net_device *dev, return 0; -del_dev: - macsec_del_dev(macsec); unlink: netdev_upper_dev_unlink(real_dev, dev); +del_dev: + macsec_del_dev(macsec); unregister: unregister_netdevice(dev); return err;
@@ -4337,7 +4337,8 @@ static int macsec_fill_info(struct sk_buff *skb, csid = secy->xpn ? MACSEC_CIPHER_ID_GCM_AES_XPN_256 : MACSEC_CIPHER_ID_GCM_AES_256; break; default: - goto nla_put_failure; + WARN_ON_ONCE(1); + return 0; } if (nla_put_sci(skb, IFLA_MACSEC_SCI, secy->sci,
--
Git-155)