1 files changed, 35 insertions, 90 deletions

diff --git a/net/socket.c b/net/socket.c
index b94c3dd71015..769c386bd428 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -312,18 +312,6 @@ static struct file_system_type sock_fs_type = {
 	.kill_sb =	kill_anon_super,
 };
 
-static int sockfs_delete_dentry(struct dentry *dentry)
-{
-	/*
-	 * At creation time, we pretended this dentry was hashed
-	 * (by clearing DCACHE_UNHASHED bit in d_flags)
-	 * At delete time, we restore the truth : not hashed.
-	 * (so that dput() can proceed correctly)
-	 */
-	dentry->d_flags |= DCACHE_UNHASHED;
-	return 0;
-}
-
 /*
  * sockfs_dname() is called from d_path().
  */
@@ -334,7 +322,6 @@ static char *sockfs_dname(struct dentry *dentry, char *buffer, int buflen)
 }
 
 static const struct dentry_operations sockfs_dentry_operations = {
-	.d_delete = sockfs_delete_dentry,
 	.d_dname  = sockfs_dname,
 };
 
@@ -355,68 +342,55 @@ static const struct dentry_operations sockfs_dentry_operations = {
  *	but we take care of internal coherence yet.
  */
 
-static int sock_alloc_fd(struct file **filep, int flags)
+static int sock_alloc_file(struct socket *sock, struct file **f, int flags)
 {
+	struct qstr name = { .name = "" };
+	struct path path;
+	struct file *file;
 	int fd;
 
 	fd = get_unused_fd_flags(flags);
-	if (likely(fd >= 0)) {
-		struct file *file = get_empty_filp();
-
-		*filep = file;
-		if (unlikely(!file)) {
-			put_unused_fd(fd);
-			return -ENFILE;
-		}
-	} else
-		*filep = NULL;
-	return fd;
-}
-
-static int sock_attach_fd(struct socket *sock, struct file *file, int flags)
-{
-	struct dentry *dentry;
-	struct qstr name = { .name = "" };
+	if (unlikely(fd < 0))
+		return fd;
 
-	dentry = d_alloc(sock_mnt->mnt_sb->s_root, &name);
-	if (unlikely(!dentry))
+	path.dentry = d_alloc(sock_mnt->mnt_sb->s_root, &name);
+	if (unlikely(!path.dentry)) {
+		put_unused_fd(fd);
 		return -ENOMEM;
+	}
+	path.mnt = mntget(sock_mnt);
 
-	dentry->d_op = &sockfs_dentry_operations;
-	/*
-	 * We dont want to push this dentry into global dentry hash table.
-	 * We pretend dentry is already hashed, by unsetting DCACHE_UNHASHED
-	 * This permits a working /proc/$pid/fd/XXX on sockets
-	 */
-	dentry->d_flags &= ~DCACHE_UNHASHED;
-	d_instantiate(dentry, SOCK_INODE(sock));
+	path.dentry->d_op = &sockfs_dentry_operations;
+	d_instantiate(path.dentry, SOCK_INODE(sock));
+	SOCK_INODE(sock)->i_fop = &socket_file_ops;
 
-	sock->file = file;
-	init_file(file, sock_mnt, dentry, FMODE_READ | FMODE_WRITE,
+	file = alloc_file(&path, FMODE_READ | FMODE_WRITE,
 		  &socket_file_ops);
-	SOCK_INODE(sock)->i_fop = &socket_file_ops;
+	if (unlikely(!file)) {
+		/* drop dentry, keep inode */
+		atomic_inc(&path.dentry->d_inode->i_count);
+		path_put(&path);
+		put_unused_fd(fd);
+		return -ENFILE;
+	}
+
+	sock->file = file;
 	file->f_flags = O_RDWR | (flags & O_NONBLOCK);
 	file->f_pos = 0;
 	file->private_data = sock;
 
-	return 0;
+	*f = file;
+	return fd;
 }
 
 int sock_map_fd(struct socket *sock, int flags)
 {
 	struct file *newfile;
-	int fd = sock_alloc_fd(&newfile, flags);
+	int fd = sock_alloc_file(sock, &newfile, flags);
 
-	if (likely(fd >= 0)) {
-		int err = sock_attach_fd(sock, newfile, flags);
-
-		if (unlikely(err < 0)) {
-			put_filp(newfile);
-			put_unused_fd(fd);
-			return err;
-		}
+	if (likely(fd >= 0))
 		fd_install(fd, newfile);
-	}
+
 	return fd;
 }
 
@@ -1390,29 +1364,19 @@ SYSCALL_DEFINE4(socketpair, int, family, int, type, int, protocol,
 	if (err < 0)
 		goto out_release_both;
 
-	fd1 = sock_alloc_fd(&newfile1, flags & O_CLOEXEC);
+	fd1 = sock_alloc_file(sock1, &newfile1, flags);
 	if (unlikely(fd1 < 0)) {
 		err = fd1;
 		goto out_release_both;
 	}
 
-	fd2 = sock_alloc_fd(&newfile2, flags & O_CLOEXEC);
+	fd2 = sock_alloc_file(sock2, &newfile2, flags);
 	if (unlikely(fd2 < 0)) {
 		err = fd2;
-		put_filp(newfile1);
-		put_unused_fd(fd1);
-		goto out_release_both;
-	}
-
-	err = sock_attach_fd(sock1, newfile1, flags & O_NONBLOCK);
-	if (unlikely(err < 0)) {
-		goto out_fd2;
-	}
-
-	err = sock_attach_fd(sock2, newfile2, flags & O_NONBLOCK);
-	if (unlikely(err < 0)) {
 		fput(newfile1);
-		goto out_fd1;
+		put_unused_fd(fd1);
+		sock_release(sock2);
+		goto out;
 	}
 
 	audit_fd_pair(fd1, fd2);
@@ -1438,16 +1402,6 @@ out_release_1:
 	sock_release(sock1);
 out:
 	return err;
-
-out_fd2:
-	put_filp(newfile1);
-	sock_release(sock1);
-out_fd1:
-	put_filp(newfile2);
-	sock_release(sock2);
-	put_unused_fd(fd1);
-	put_unused_fd(fd2);
-	goto out;
 }
 
 /*
@@ -1551,17 +1505,13 @@ SYSCALL_DEFINE4(accept4, int, fd, struct sockaddr __user *, upeer_sockaddr,
 	 */
 	__module_get(newsock->ops->owner);
 
-	newfd = sock_alloc_fd(&newfile, flags & O_CLOEXEC);
+	newfd = sock_alloc_file(newsock, &newfile, flags);
 	if (unlikely(newfd < 0)) {
 		err = newfd;
 		sock_release(newsock);
 		goto out_put;
 	}
 
-	err = sock_attach_fd(newsock, newfile, flags & O_NONBLOCK);
-	if (err < 0)
-		goto out_fd_simple;
-
 	err = security_socket_accept(sock, newsock);
 	if (err)
 		goto out_fd;
@@ -1591,11 +1541,6 @@ out_put:
 	fput_light(sock->file, fput_needed);
 out:
 	return err;
-out_fd_simple:
-	sock_release(newsock);
-	put_filp(newfile);
-	put_unused_fd(newfd);
-	goto out_put;
 out_fd:
 	fput(newfile);
 	put_unused_fd(newfd);