From 8965c160b8f7333df895321c8aa6bad4a7175f2b Mon Sep 17 00:00:00 2001 From: Stanislav Fomichev Date: Tue, 1 Apr 2025 09:34:44 -0700 Subject: [PATCH] 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 Fixes: ad7c7b2172c3 ("net: hold netdev instance lock during sysfs operations") Signed-off-by: Stanislav Fomichev Link: https://patch.msgid.link/20250401163452.622454-4-sdf@fomichev.me Signed-off-by: Jakub Kicinski --- include/net/ip.h | 16 ++++++++-------- net/core/dev.c | 1 + net/ipv6/addrconf.c | 15 +++++++++++++-- 3 files changed, 22 insertions(+), 10 deletions(-) diff --git a/include/net/ip.h b/include/net/ip.h index 8a48ade24620..47ed6d23853d 100644 --- 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 #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 ce6612106e60..0608605cfc24 100644 --- 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 54a8ea004da2..c3b908fccbc1 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -80,6 +80,7 @@ #include #include #include +#include #include #include #include @@ -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); } } }