diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index e46c830c88d88988cf7130452bd94ec5cbf55aa8..e9929abeb9327b9d5ff7ca30d7a23aab7005b974 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1567,6 +1567,8 @@ extern int call_netdevice_notifiers(unsigned long val, struct net_device *dev); extern rwlock_t dev_base_lock; /* Device list lock */ +extern seqlock_t devnet_rename_seq; /* Device rename lock */ + #define for_each_netdev(net, d) \ list_for_each_entry(d, &(net)->dev_base_head, dev_list) diff --git a/net/core/dev.c b/net/core/dev.c index 7304ea8a1f13a15097619c68d14820e963695573..2a5f5586642923005e3730cb05a9c05edd83db9f 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -203,6 +203,8 @@ static struct list_head offload_base __read_mostly; DEFINE_RWLOCK(dev_base_lock); EXPORT_SYMBOL(dev_base_lock); +DEFINE_SEQLOCK(devnet_rename_seq); + static inline void dev_base_seq_inc(struct net *net) { while (++net->dev_base_seq == 0); @@ -1091,22 +1093,31 @@ int dev_change_name(struct net_device *dev, const char *newname) if (dev->flags & IFF_UP) return -EBUSY; - if (strncmp(newname, dev->name, IFNAMSIZ) == 0) + write_seqlock(&devnet_rename_seq); + + if (strncmp(newname, dev->name, IFNAMSIZ) == 0) { + write_sequnlock(&devnet_rename_seq); return 0; + } memcpy(oldname, dev->name, IFNAMSIZ); err = dev_get_valid_name(net, dev, newname); - if (err < 0) + if (err < 0) { + write_sequnlock(&devnet_rename_seq); return err; + } rollback: ret = device_rename(&dev->dev, dev->name); if (ret) { memcpy(dev->name, oldname, IFNAMSIZ); + write_sequnlock(&devnet_rename_seq); return ret; } + write_sequnlock(&devnet_rename_seq); + write_lock_bh(&dev_base_lock); hlist_del_rcu(&dev->name_hlist); write_unlock_bh(&dev_base_lock); @@ -1124,6 +1135,7 @@ int dev_change_name(struct net_device *dev, const char *newname) /* err >= 0 after dev_alloc_name() or stores the first errno */ if (err >= 0) { err = ret; + write_seqlock(&devnet_rename_seq); memcpy(dev->name, oldname, IFNAMSIZ); goto rollback; } else { @@ -4148,6 +4160,7 @@ static int dev_ifname(struct net *net, struct ifreq __user *arg) { struct net_device *dev; struct ifreq ifr; + unsigned seq; /* * Fetch the caller's info block. @@ -4156,6 +4169,8 @@ static int dev_ifname(struct net *net, struct ifreq __user *arg) if (copy_from_user(&ifr, arg, sizeof(struct ifreq))) return -EFAULT; +retry: + seq = read_seqbegin(&devnet_rename_seq); rcu_read_lock(); dev = dev_get_by_index_rcu(net, ifr.ifr_ifindex); if (!dev) { @@ -4165,6 +4180,8 @@ static int dev_ifname(struct net *net, struct ifreq __user *arg) strcpy(ifr.ifr_name, dev->name); rcu_read_unlock(); + if (read_seqretry(&devnet_rename_seq, seq)) + goto retry; if (copy_to_user(arg, &ifr, sizeof(struct ifreq))) return -EFAULT; diff --git a/net/core/sock.c b/net/core/sock.c index d4f7b58b3866e4763e50de6e81c7c82e1b3a7160..a692ef49c9bb9b2d996f0538049a135a93c26812 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -505,7 +505,8 @@ struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie) } EXPORT_SYMBOL(sk_dst_check); -static int sock_bindtodevice(struct sock *sk, char __user *optval, int optlen) +static int sock_setbindtodevice(struct sock *sk, char __user *optval, + int optlen) { int ret = -ENOPROTOOPT; #ifdef CONFIG_NETDEVICES @@ -562,6 +563,59 @@ static int sock_bindtodevice(struct sock *sk, char __user *optval, int optlen) return ret; } +static int sock_getbindtodevice(struct sock *sk, char __user *optval, + int __user *optlen, int len) +{ + int ret = -ENOPROTOOPT; +#ifdef CONFIG_NETDEVICES + struct net *net = sock_net(sk); + struct net_device *dev; + char devname[IFNAMSIZ]; + unsigned seq; + + if (sk->sk_bound_dev_if == 0) { + len = 0; + goto zero; + } + + ret = -EINVAL; + if (len < IFNAMSIZ) + goto out; + +retry: + seq = read_seqbegin(&devnet_rename_seq); + rcu_read_lock(); + dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if); + ret = -ENODEV; + if (!dev) { + rcu_read_unlock(); + goto out; + } + + strcpy(devname, dev->name); + rcu_read_unlock(); + if (read_seqretry(&devnet_rename_seq, seq)) + goto retry; + + len = strlen(devname) + 1; + + ret = -EFAULT; + if (copy_to_user(optval, devname, len)) + goto out; + +zero: + ret = -EFAULT; + if (put_user(len, optlen)) + goto out; + + ret = 0; + +out: +#endif + + return ret; +} + static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool) { if (valbool) @@ -589,7 +643,7 @@ int sock_setsockopt(struct socket *sock, int level, int optname, */ if (optname == SO_BINDTODEVICE) - return sock_bindtodevice(sk, optval, optlen); + return sock_setbindtodevice(sk, optval, optlen); if (optlen < sizeof(int)) return -EINVAL; @@ -1075,15 +1129,17 @@ int sock_getsockopt(struct socket *sock, int level, int optname, case SO_NOFCS: v.val = sock_flag(sk, SOCK_NOFCS); break; + case SO_BINDTODEVICE: - v.val = sk->sk_bound_dev_if; - break; + return sock_getbindtodevice(sk, optval, optlen, len); + case SO_GET_FILTER: len = sk_get_filter(sk, (struct sock_filter __user *)optval, len); if (len < 0) return len; goto lenout; + default: return -ENOPROTOOPT; }