1 files changed, 46 insertions, 85 deletions

diff --git a/net/socket.c b/net/socket.c
index 42d8e9c9ccd5..bbd2e9ceb692 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -163,12 +163,6 @@ static DEFINE_SPINLOCK(net_family_lock);
 static const struct net_proto_family __rcu *net_families[NPROTO] __read_mostly;
 
 /*
- *	Statistics counters of the socket lists
- */
-
-static DEFINE_PER_CPU(int, sockets_in_use);
-
-/*
  * Support routines.
  * Move socket addresses back and forth across the kernel/user
  * divide and look after the messy bits.
@@ -406,8 +400,10 @@ struct file *sock_alloc_file(struct socket *sock, int flags, const char *dname)
 		name.len = strlen(name.name);
 	}
 	path.dentry = d_alloc_pseudo(sock_mnt->mnt_sb, &name);
-	if (unlikely(!path.dentry))
+	if (unlikely(!path.dentry)) {
+		sock_release(sock);
 		return ERR_PTR(-ENOMEM);
+	}
 	path.mnt = mntget(sock_mnt);
 
 	d_instantiate(path.dentry, SOCK_INODE(sock));
@@ -415,9 +411,11 @@ struct file *sock_alloc_file(struct socket *sock, int flags, const char *dname)
 	file = alloc_file(&path, FMODE_READ | FMODE_WRITE,
 		  &socket_file_ops);
 	if (IS_ERR(file)) {
-		/* drop dentry, keep inode */
+		/* drop dentry, keep inode for a bit */
 		ihold(d_inode(path.dentry));
 		path_put(&path);
+		/* ... and now kill it properly */
+		sock_release(sock);
 		return file;
 	}
 
@@ -574,7 +572,6 @@ struct socket *sock_alloc(void)
 	inode->i_gid = current_fsgid();
 	inode->i_op = &sockfs_inode_ops;
 
-	this_cpu_add(sockets_in_use, 1);
 	return sock;
 }
 EXPORT_SYMBOL(sock_alloc);
@@ -601,7 +598,6 @@ void sock_release(struct socket *sock)
 	if (rcu_dereference_protected(sock->wq, 1)->fasync_list)
 		pr_err("%s: fasync list not empty!\n", __func__);
 
-	this_cpu_sub(sockets_in_use, 1);
 	if (!sock->file) {
 		iput(SOCK_INODE(sock));
 		return;
@@ -1330,19 +1326,9 @@ SYSCALL_DEFINE3(socket, int, family, int, type, int, protocol)
 
 	retval = sock_create(family, type, protocol, &sock);
 	if (retval < 0)
-		goto out;
-
-	retval = sock_map_fd(sock, flags & (O_CLOEXEC | O_NONBLOCK));
-	if (retval < 0)
-		goto out_release;
+		return retval;
 
-out:
-	/* It may be already another descriptor 8) Not kernel problem. */
-	return retval;
-
-out_release:
-	sock_release(sock);
-	return retval;
+	return sock_map_fd(sock, flags & (O_CLOEXEC | O_NONBLOCK));
 }
 
 /*
@@ -1366,87 +1352,72 @@ SYSCALL_DEFINE4(socketpair, int, family, int, type, int, protocol,
 		flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
 
 	/*
+	 * reserve descriptors and make sure we won't fail
+	 * to return them to userland.
+	 */
+	fd1 = get_unused_fd_flags(flags);
+	if (unlikely(fd1 < 0))
+		return fd1;
+
+	fd2 = get_unused_fd_flags(flags);
+	if (unlikely(fd2 < 0)) {
+		put_unused_fd(fd1);
+		return fd2;
+	}
+
+	err = put_user(fd1, &usockvec[0]);
+	if (err)
+		goto out;
+
+	err = put_user(fd2, &usockvec[1]);
+	if (err)
+		goto out;
+
+	/*
 	 * Obtain the first socket and check if the underlying protocol
 	 * supports the socketpair call.
 	 */
 
 	err = sock_create(family, type, protocol, &sock1);
-	if (err < 0)
+	if (unlikely(err < 0))
 		goto out;
 
 	err = sock_create(family, type, protocol, &sock2);
-	if (err < 0)
-		goto out_release_1;
-
-	err = sock1->ops->socketpair(sock1, sock2);
-	if (err < 0)
-		goto out_release_both;
-
-	fd1 = get_unused_fd_flags(flags);
-	if (unlikely(fd1 < 0)) {
-		err = fd1;
-		goto out_release_both;
+	if (unlikely(err < 0)) {
+		sock_release(sock1);
+		goto out;
 	}
 
-	fd2 = get_unused_fd_flags(flags);
-	if (unlikely(fd2 < 0)) {
-		err = fd2;
-		goto out_put_unused_1;
+	err = sock1->ops->socketpair(sock1, sock2);
+	if (unlikely(err < 0)) {
+		sock_release(sock2);
+		sock_release(sock1);
+		goto out;
 	}
 
 	newfile1 = sock_alloc_file(sock1, flags, NULL);
 	if (IS_ERR(newfile1)) {
 		err = PTR_ERR(newfile1);
-		goto out_put_unused_both;
+		sock_release(sock2);
+		goto out;
 	}
 
 	newfile2 = sock_alloc_file(sock2, flags, NULL);
 	if (IS_ERR(newfile2)) {
 		err = PTR_ERR(newfile2);
-		goto out_fput_1;
+		fput(newfile1);
+		goto out;
 	}
 
-	err = put_user(fd1, &usockvec[0]);
-	if (err)
-		goto out_fput_both;
-
-	err = put_user(fd2, &usockvec[1]);
-	if (err)
-		goto out_fput_both;
-
 	audit_fd_pair(fd1, fd2);
 
 	fd_install(fd1, newfile1);
 	fd_install(fd2, newfile2);
-	/* fd1 and fd2 may be already another descriptors.
-	 * Not kernel problem.
-	 */
-
 	return 0;
 
-out_fput_both:
-	fput(newfile2);
-	fput(newfile1);
-	put_unused_fd(fd2);
-	put_unused_fd(fd1);
-	goto out;
-
-out_fput_1:
-	fput(newfile1);
-	put_unused_fd(fd2);
-	put_unused_fd(fd1);
-	sock_release(sock2);
-	goto out;
-
-out_put_unused_both:
+out:
 	put_unused_fd(fd2);
-out_put_unused_1:
 	put_unused_fd(fd1);
-out_release_both:
-	sock_release(sock2);
-out_release_1:
-	sock_release(sock1);
-out:
 	return err;
 }
 
@@ -1562,7 +1533,6 @@ SYSCALL_DEFINE4(accept4, int, fd, struct sockaddr __user *, upeer_sockaddr,
 	if (IS_ERR(newfile)) {
 		err = PTR_ERR(newfile);
 		put_unused_fd(newfd);
-		sock_release(newsock);
 		goto out_put;
 	}
 
@@ -2644,17 +2614,8 @@ core_initcall(sock_init);	/* early initcall */
 #ifdef CONFIG_PROC_FS
 void socket_seq_show(struct seq_file *seq)
 {
-	int cpu;
-	int counter = 0;
-
-	for_each_possible_cpu(cpu)
-	    counter += per_cpu(sockets_in_use, cpu);
-
-	/* It can be negative, by the way. 8) */
-	if (counter < 0)
-		counter = 0;
-
-	seq_printf(seq, "sockets: used %d\n", counter);
+	seq_printf(seq, "sockets: used %d\n",
+		   sock_inuse_get(seq->private));
 }
 #endif				/* CONFIG_PROC_FS */