Merge tag 'pull-filename' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs 'struct filename' updates from Al Viro:
 "[Mostly] sanitize struct filename handling"

* tag 'pull-filename' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (68 commits)
  sysfs(2): fs_index() argument is _not_ a pathname
  alpha: switch osf_mount() to strndup_user()
  ksmbd: use CLASS(filename_kernel)
  mqueue: switch to CLASS(filename)
  user_statfs(): switch to CLASS(filename)
  statx: switch to CLASS(filename_maybe_null)
  quotactl_block(): switch to CLASS(filename)
  chroot(2): switch to CLASS(filename)
  move_mount(2): switch to CLASS(filename_maybe_null)
  namei.c: switch user pathname imports to CLASS(filename{,_flags})
  namei.c: convert getname_kernel() callers to CLASS(filename_kernel)
  do_f{chmod,chown,access}at(): use CLASS(filename_uflags)
  do_readlinkat(): switch to CLASS(filename_flags)
  do_sys_truncate(): switch to CLASS(filename)
  do_utimes_path(): switch to CLASS(filename_uflags)
  chdir(2): unspaghettify a bit...
  do_fchownat(): unspaghettify a bit...
  fspick(2): use CLASS(filename_flags)
  name_to_handle_at(): use CLASS(filename_uflags)
  vfs_open_tree(): use CLASS(filename_uflags)
  ...

1 files changed, 47 insertions, 72 deletions

diff --git a/fs/open.c b/fs/open.c
index 74c4c1462b3e..91f1139591ab 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -135,15 +135,16 @@ int do_sys_truncate(const char __user *pathname, loff_t length)
 	if (length < 0)	/* sorry, but loff_t says... */
 		return -EINVAL;
 
+	CLASS(filename, name)(pathname);
 retry:
-	error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path);
+	error = filename_lookup(AT_FDCWD, name, lookup_flags, &path, NULL);
 	if (!error) {
 		error = vfs_truncate(&path, length);
 		path_put(&path);
-	}
-	if (retry_estale(error, lookup_flags)) {
-		lookup_flags |= LOOKUP_REVAL;
-		goto retry;
+		if (retry_estale(error, lookup_flags)) {
+			lookup_flags |= LOOKUP_REVAL;
+			goto retry;
+		}
 	}
 	return error;
 }
@@ -477,8 +478,6 @@ static int do_faccessat(int dfd, const char __user *filename, int mode, int flag
 
 	if (flags & AT_SYMLINK_NOFOLLOW)
 		lookup_flags &= ~LOOKUP_FOLLOW;
-	if (flags & AT_EMPTY_PATH)
-		lookup_flags |= LOOKUP_EMPTY;
 
 	if (access_need_override_creds(flags)) {
 		old_cred = access_override_creds();
@@ -486,8 +485,9 @@ static int do_faccessat(int dfd, const char __user *filename, int mode, int flag
 			return -ENOMEM;
 	}
 
+	CLASS(filename_uflags, name)(filename, flags);
 retry:
-	res = user_path_at(dfd, filename, lookup_flags, &path);
+	res = filename_lookup(dfd, name, lookup_flags, &path, NULL);
 	if (res)
 		goto out;
 
@@ -554,24 +554,19 @@ SYSCALL_DEFINE1(chdir, const char __user *, filename)
 	struct path path;
 	int error;
 	unsigned int lookup_flags = LOOKUP_FOLLOW | LOOKUP_DIRECTORY;
+	CLASS(filename, name)(filename);
 retry:
-	error = user_path_at(AT_FDCWD, filename, lookup_flags, &path);
-	if (error)
-		goto out;
-
-	error = path_permission(&path, MAY_EXEC | MAY_CHDIR);
-	if (error)
-		goto dput_and_out;
-
-	set_fs_pwd(current->fs, &path);
-
-dput_and_out:
-	path_put(&path);
-	if (retry_estale(error, lookup_flags)) {
-		lookup_flags |= LOOKUP_REVAL;
-		goto retry;
+	error = filename_lookup(AT_FDCWD, name, lookup_flags, &path, NULL);
+	if (!error) {
+		error = path_permission(&path, MAY_EXEC | MAY_CHDIR);
+		if (!error)
+			set_fs_pwd(current->fs, &path);
+		path_put(&path);
+		if (retry_estale(error, lookup_flags)) {
+			lookup_flags |= LOOKUP_REVAL;
+			goto retry;
+		}
 	}
-out:
 	return error;
 }
 
@@ -597,10 +592,11 @@ SYSCALL_DEFINE1(chroot, const char __user *, filename)
 	struct path path;
 	int error;
 	unsigned int lookup_flags = LOOKUP_FOLLOW | LOOKUP_DIRECTORY;
+	CLASS(filename, name)(filename);
 retry:
-	error = user_path_at(AT_FDCWD, filename, lookup_flags, &path);
+	error = filename_lookup(AT_FDCWD, name, lookup_flags, &path, NULL);
 	if (error)
-		goto out;
+		return error;
 
 	error = path_permission(&path, MAY_EXEC | MAY_CHDIR);
 	if (error)
@@ -610,18 +606,14 @@ retry:
 	if (!ns_capable(current_user_ns(), CAP_SYS_CHROOT))
 		goto dput_and_out;
 	error = security_path_chroot(&path);
-	if (error)
-		goto dput_and_out;
-
-	set_fs_root(current->fs, &path);
-	error = 0;
+	if (!error)
+		set_fs_root(current->fs, &path);
 dput_and_out:
 	path_put(&path);
 	if (retry_estale(error, lookup_flags)) {
 		lookup_flags |= LOOKUP_REVAL;
 		goto retry;
 	}
-out:
 	return error;
 }
 
@@ -685,11 +677,9 @@ static int do_fchmodat(int dfd, const char __user *filename, umode_t mode,
 		return -EINVAL;
 
 	lookup_flags = (flags & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW;
-	if (flags & AT_EMPTY_PATH)
-		lookup_flags |= LOOKUP_EMPTY;
-
+	CLASS(filename_uflags, name)(filename, flags);
 retry:
-	error = user_path_at(dfd, filename, lookup_flags, &path);
+	error = filename_lookup(dfd, name, lookup_flags, &path, NULL);
 	if (!error) {
 		error = chmod_common(&path, mode);
 		path_put(&path);
@@ -800,31 +790,28 @@ int do_fchownat(int dfd, const char __user *filename, uid_t user, gid_t group,
 		int flag)
 {
 	struct path path;
-	int error = -EINVAL;
+	int error;
 	int lookup_flags;
 
 	if ((flag & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0)
-		goto out;
+		return -EINVAL;
 
 	lookup_flags = (flag & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW;
-	if (flag & AT_EMPTY_PATH)
-		lookup_flags |= LOOKUP_EMPTY;
+	CLASS(filename_uflags, name)(filename, flag);
 retry:
-	error = user_path_at(dfd, filename, lookup_flags, &path);
-	if (error)
-		goto out;
-	error = mnt_want_write(path.mnt);
-	if (error)
-		goto out_release;
-	error = chown_common(&path, user, group);
-	mnt_drop_write(path.mnt);
-out_release:
-	path_put(&path);
-	if (retry_estale(error, lookup_flags)) {
-		lookup_flags |= LOOKUP_REVAL;
-		goto retry;
+	error = filename_lookup(dfd, name, lookup_flags, &path, NULL);
+	if (!error) {
+		error = mnt_want_write(path.mnt);
+		if (!error) {
+			error = chown_common(&path, user, group);
+			mnt_drop_write(path.mnt);
+		}
+		path_put(&path);
+		if (retry_estale(error, lookup_flags)) {
+			lookup_flags |= LOOKUP_REVAL;
+			goto retry;
+		}
 	}
-out:
 	return error;
 }
 
@@ -1334,7 +1321,7 @@ struct file *file_open_name(struct filename *name, int flags, umode_t mode)
 	int err = build_open_flags(&how, &op);
 	if (err)
 		return ERR_PTR(err);
-	return do_filp_open(AT_FDCWD, name, &op);
+	return do_file_open(AT_FDCWD, name, &op);
 }
 
 /**
@@ -1350,14 +1337,8 @@ struct file *file_open_name(struct filename *name, int flags, umode_t mode)
  */
 struct file *filp_open(const char *filename, int flags, umode_t mode)
 {
-	struct filename *name = getname_kernel(filename);
-	struct file *file = ERR_CAST(name);
-
-	if (!IS_ERR(name)) {
-		file = file_open_name(name, flags, mode);
-		putname(name);
-	}
-	return file;
+	CLASS(filename_kernel, name)(filename);
+	return file_open_name(name, flags, mode);
 }
 EXPORT_SYMBOL(filp_open);
 
@@ -1377,18 +1358,12 @@ static int do_sys_openat2(int dfd, const char __user *filename,
 			  struct open_how *how)
 {
 	struct open_flags op;
-	struct filename *tmp __free(putname) = NULL;
-	int err;
-
-	err = build_open_flags(how, &op);
+	int err = build_open_flags(how, &op);
 	if (unlikely(err))
 		return err;
 
-	tmp = getname(filename);
-	if (IS_ERR(tmp))
-		return PTR_ERR(tmp);
-
-	return FD_ADD(how->flags, do_filp_open(dfd, tmp, &op));
+	CLASS(filename, name)(filename);
+	return FD_ADD(how->flags, do_file_open(dfd, name, &op));
 }
 
 int do_sys_open(int dfd, const char __user *filename, int flags, umode_t mode)