1 files changed, 23 insertions, 21 deletions

diff --git a/fs/open.c b/fs/open.c
index d98e19239bb7..0285ce7dbd51 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -68,7 +68,6 @@ int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs,
 long vfs_truncate(const struct path *path, loff_t length)
 {
 	struct inode *inode;
-	struct dentry *upperdentry;
 	long error;
 
 	inode = path->dentry->d_inode;
@@ -91,17 +90,7 @@ long vfs_truncate(const struct path *path, loff_t length)
 	if (IS_APPEND(inode))
 		goto mnt_drop_write_and_out;
 
-	/*
-	 * If this is an overlayfs then do as if opening the file so we get
-	 * write access on the upper inode, not on the overlay inode.  For
-	 * non-overlay filesystems d_real() is an identity function.
-	 */
-	upperdentry = d_real(path->dentry, NULL, O_WRONLY, 0);
-	error = PTR_ERR(upperdentry);
-	if (IS_ERR(upperdentry))
-		goto mnt_drop_write_and_out;
-
-	error = get_write_access(upperdentry->d_inode);
+	error = get_write_access(inode);
 	if (error)
 		goto mnt_drop_write_and_out;
 
@@ -120,7 +109,7 @@ long vfs_truncate(const struct path *path, loff_t length)
 		error = do_truncate(path->dentry, length, 0, NULL);
 
 put_write_and_out:
-	put_write_access(upperdentry->d_inode);
+	put_write_access(inode);
 mnt_drop_write_and_out:
 	mnt_drop_write(path->mnt);
 out:
@@ -707,12 +696,12 @@ int ksys_fchown(unsigned int fd, uid_t user, gid_t group)
 	if (!f.file)
 		goto out;
 
-	error = mnt_want_write_file_path(f.file);
+	error = mnt_want_write_file(f.file);
 	if (error)
 		goto out_fput;
 	audit_file(f.file);
 	error = chown_common(&f.file->f_path, user, group);
-	mnt_drop_write_file_path(f.file);
+	mnt_drop_write_file(f.file);
 out_fput:
 	fdput(f);
 out:
@@ -887,13 +876,8 @@ EXPORT_SYMBOL(file_path);
  */
 int vfs_open(const struct path *path, struct file *file)
 {
-	struct dentry *dentry = d_real(path->dentry, NULL, file->f_flags, 0);
-
-	if (IS_ERR(dentry))
-		return PTR_ERR(dentry);
-
 	file->f_path = *path;
-	return do_dentry_open(file, d_backing_inode(dentry), NULL);
+	return do_dentry_open(file, d_backing_inode(path->dentry), NULL);
 }
 
 struct file *dentry_open(const struct path *path, int flags,
@@ -919,6 +903,24 @@ struct file *dentry_open(const struct path *path, int flags,
 }
 EXPORT_SYMBOL(dentry_open);
 
+struct file *open_with_fake_path(const struct path *path, int flags,
+				struct inode *inode, const struct cred *cred)
+{
+	struct file *f = alloc_empty_file_noaccount(flags, cred);
+	if (!IS_ERR(f)) {
+		int error;
+
+		f->f_path = *path;
+		error = do_dentry_open(f, inode, NULL);
+		if (error) {
+			fput(f);
+			f = ERR_PTR(error);
+		}
+	}
+	return f;
+}
+EXPORT_SYMBOL(open_with_fake_path);
+
 static inline int build_open_flags(int flags, umode_t mode, struct open_flags *op)
 {
 	int lookup_flags = 0;