From: Miklos Szeredi <mszeredi@redhat.com>
Date: Fri, 6 Jul 2018 21:57:06 +0000 (+0200)
Subject: vfs: don't open real
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=a6518f73e60e5044656d1ba587e7463479a9381a;p=linux.git

vfs: don't open real

Let overlayfs do its thing when opening a file.

This enables stacking and fixes the corner case when a file is opened for
read, modified through a writable open, and data is read from the read-only
file.  After this patch the read-only open will not return stale data even
in this case.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---

diff --git a/fs/open.c b/fs/open.c
index 9c6617dbb2c06..fed24862ef839 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -893,13 +893,8 @@ 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,