net: use netif_disable_lro in ipv6_add_dev

ipv6_add_dev might call dev_disable_lro which unconditionally grabs
instance lock, so it will deadlock during NETDEV_REGISTER. Switch
to netif_disable_lro.

Make sure all callers hold the instance lock as well.

Cc: Cosmin Ratiu <cratiu@nvidia.com>
Fixes: ad7c7b2172c3 ("net: hold netdev instance lock during sysfs operations")
Signed-off-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250401163452.622454-4-sdf@fomichev.me
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/include/net/ip.h b/include/net/ip.h
index 8a48ade24620b4c8e2ebb4726f27a69aac7138b0..47ed6d23853d7712aec4df15771d71ab80b80cf9 100644 (file)
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -667,14 +667,6 @@ static inline void ip_ipgre_mc_map(__be32 naddr, const unsigned char *broadcast,
                memcpy(buf, &naddr, sizeof(naddr));
 }
 
-#if IS_MODULE(CONFIG_IPV6)
-#define EXPORT_IPV6_MOD(X) EXPORT_SYMBOL(X)
-#define EXPORT_IPV6_MOD_GPL(X) EXPORT_SYMBOL_GPL(X)
-#else
-#define EXPORT_IPV6_MOD(X)
-#define EXPORT_IPV6_MOD_GPL(X)
-#endif
-
 #if IS_ENABLED(CONFIG_IPV6)
 #include <linux/ipv6.h>
 #endif
@@ -694,6 +686,14 @@ static __inline__ void inet_reset_saddr(struct sock *sk)
 
 #endif
 
+#if IS_MODULE(CONFIG_IPV6)
+#define EXPORT_IPV6_MOD(X) EXPORT_SYMBOL(X)
+#define EXPORT_IPV6_MOD_GPL(X) EXPORT_SYMBOL_GPL(X)
+#else
+#define EXPORT_IPV6_MOD(X)
+#define EXPORT_IPV6_MOD_GPL(X)
+#endif
+
 static inline unsigned int ipv4_addr_hash(__be32 ip)
 {
        return (__force unsigned int) ip;

diff --git a/net/core/dev.c b/net/core/dev.c
index ce6612106e60695e755b162bea895e33c88cbd1c..0608605cfc242fc0a3db7032741303c9db21ef74 100644 (file)
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1771,6 +1771,7 @@ void netif_disable_lro(struct net_device *dev)
                netdev_unlock_ops(lower_dev);
        }
 }
+EXPORT_IPV6_MOD(netif_disable_lro);
 
 /**
  *     dev_disable_gro_hw - disable HW Generic Receive Offload on a device

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 54a8ea004da286c6a3cffb3c6b0f73acdae1ffd1..c3b908fccbc1430b0668deebe4b8a445f9762803 100644 (file)
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -80,6 +80,7 @@
 #include <net/netlink.h>
 #include <net/pkt_sched.h>
 #include <net/l3mdev.h>
+#include <net/netdev_lock.h>
 #include <linux/if_tunnel.h>
 #include <linux/rtnetlink.h>
 #include <linux/netconf.h>
@@ -377,6 +378,7 @@ static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
        int err = -ENOMEM;
 
        ASSERT_RTNL();
+       netdev_ops_assert_locked(dev);
 
        if (dev->mtu < IPV6_MIN_MTU && dev != blackhole_netdev)
                return ERR_PTR(-EINVAL);
@@ -402,7 +404,7 @@ static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
                return ERR_PTR(err);
        }
        if (ndev->cnf.forwarding)
-               dev_disable_lro(dev);
+               netif_disable_lro(dev);
        /* We refer to the device */
        netdev_hold(dev, &ndev->dev_tracker, GFP_KERNEL);
 
@@ -3152,10 +3154,12 @@ int addrconf_add_ifaddr(struct net *net, void __user *arg)
 
        rtnl_net_lock(net);
        dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
+       netdev_lock_ops(dev);
        if (dev)
                err = inet6_addr_add(net, dev, &cfg, 0, 0, NULL);
        else
                err = -ENODEV;
+       netdev_unlock_ops(dev);
        rtnl_net_unlock(net);
        return err;
 }
@@ -5026,9 +5030,10 @@ inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
        if (!dev) {
                NL_SET_ERR_MSG_MOD(extack, "Unable to find the interface");
                err = -ENODEV;
-               goto unlock;
+               goto unlock_rtnl;
        }
 
+       netdev_lock_ops(dev);
        idev = ipv6_find_idev(dev);
        if (IS_ERR(idev)) {
                err = PTR_ERR(idev);
@@ -5065,6 +5070,8 @@ inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
 
        in6_ifa_put(ifa);
 unlock:
+       netdev_unlock_ops(dev);
+unlock_rtnl:
        rtnl_net_unlock(net);
 
        return err;
@@ -6516,7 +6523,9 @@ static int addrconf_sysctl_addr_gen_mode(const struct ctl_table *ctl, int write,
 
                        if (idev->cnf.addr_gen_mode != new_val) {
                                WRITE_ONCE(idev->cnf.addr_gen_mode, new_val);
+                               netdev_lock_ops(idev->dev);
                                addrconf_init_auto_addrs(idev->dev);
+                               netdev_unlock_ops(idev->dev);
                        }
                } else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
                        struct net_device *dev;
@@ -6528,7 +6537,9 @@ static int addrconf_sysctl_addr_gen_mode(const struct ctl_table *ctl, int write,
                                    idev->cnf.addr_gen_mode != new_val) {
                                        WRITE_ONCE(idev->cnf.addr_gen_mode,
                                                  new_val);
+                                       netdev_lock_ops(idev->dev);
                                        addrconf_init_auto_addrs(idev->dev);
+                                       netdev_unlock_ops(idev->dev);
                                }
                        }
                }