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);