diff options
Diffstat (limited to 'net/socket.c')
| -rw-r--r-- | net/socket.c | 50 |
1 files changed, 41 insertions, 9 deletions
diff --git a/net/socket.c b/net/socket.c index 3ca2fd9e372..ccc576a6a50 100644 --- a/net/socket.c +++ b/net/socket.c @@ -156,7 +156,7 @@ static const struct file_operations socket_file_ops = { */ static DEFINE_SPINLOCK(net_family_lock); -static const struct net_proto_family *net_families[NPROTO] __read_mostly; +static const struct net_proto_family __rcu *net_families[NPROTO] __read_mostly; /* * Statistics counters of the socket lists @@ -262,6 +262,7 @@ static struct inode *sock_alloc_inode(struct super_block *sb) } + static void wq_free_rcu(struct rcu_head *head) { struct socket_wq *wq = container_of(head, struct socket_wq, rcu); @@ -360,14 +361,14 @@ static int sock_alloc_file(struct socket *sock, struct file **f, int flags) if (unlikely(fd < 0)) return fd; - path.dentry = d_alloc(sock_mnt->mnt_sb->s_root, &name); + path.dentry = d_alloc_pseudo(sock_mnt->mnt_sb, &name); if (unlikely(!path.dentry)) { put_unused_fd(fd); return -ENOMEM; } path.mnt = mntget(sock_mnt); - path.dentry->d_op = &sockfs_dentry_operations; + d_set_d_op(path.dentry, &sockfs_dentry_operations); d_instantiate(path.dentry, SOCK_INODE(sock)); SOCK_INODE(sock)->i_fop = &socket_file_ops; @@ -732,6 +733,21 @@ static int sock_recvmsg_nosec(struct socket *sock, struct msghdr *msg, return ret; } +/** + * kernel_recvmsg - Receive a message from a socket (kernel space) + * @sock: The socket to receive the message from + * @msg: Received message + * @vec: Input s/g array for message data + * @num: Size of input s/g array + * @size: Number of bytes to read + * @flags: Message flags (MSG_DONTWAIT, etc...) + * + * On return the msg structure contains the scatter/gather array passed in the + * vec argument. The array is modified so that it consists of the unfilled + * portion of the original array. + * + * The returned value is the total number of bytes received, or an error. + */ int kernel_recvmsg(struct socket *sock, struct msghdr *msg, struct kvec *vec, size_t num, size_t size, int flags) { @@ -1200,7 +1216,7 @@ int __sock_create(struct net *net, int family, int type, int protocol, * requested real, full-featured networking support upon configuration. * Otherwise module support will break! */ - if (net_families[family] == NULL) + if (rcu_access_pointer(net_families[family]) == NULL) request_module("net-pf-%d", family); #endif @@ -2332,10 +2348,11 @@ int sock_register(const struct net_proto_family *ops) } spin_lock(&net_family_lock); - if (net_families[ops->family]) + if (rcu_dereference_protected(net_families[ops->family], + lockdep_is_held(&net_family_lock))) err = -EEXIST; else { - net_families[ops->family] = ops; + rcu_assign_pointer(net_families[ops->family], ops); err = 0; } spin_unlock(&net_family_lock); @@ -2363,7 +2380,7 @@ void sock_unregister(int family) BUG_ON(family < 0 || family >= NPROTO); spin_lock(&net_family_lock); - net_families[family] = NULL; + rcu_assign_pointer(net_families[family], NULL); spin_unlock(&net_family_lock); synchronize_rcu(); @@ -2374,6 +2391,8 @@ EXPORT_SYMBOL(sock_unregister); static int __init sock_init(void) { + int err; + /* * Initialize sock SLAB cache. */ @@ -2390,8 +2409,15 @@ static int __init sock_init(void) */ init_inodecache(); - register_filesystem(&sock_fs_type); + + err = register_filesystem(&sock_fs_type); + if (err) + goto out_fs; sock_mnt = kern_mount(&sock_fs_type); + if (IS_ERR(sock_mnt)) { + err = PTR_ERR(sock_mnt); + goto out_mount; + } /* The real protocol initialization is performed in later initcalls. */ @@ -2404,7 +2430,13 @@ static int __init sock_init(void) skb_timestamping_init(); #endif - return 0; +out: + return err; + +out_mount: + unregister_filesystem(&sock_fs_type); +out_fs: + goto out; } core_initcall(sock_init); /* early initcall */ |