overlay: Call ovl_drop_write() earlier in ovl_dentry_open()

Call ovl_drop_write() earlier in ovl_dentry_open() before we call vfs_open()
as we've done the copy up for which we needed the freeze-write lock by that
point.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 4 insertions, 10 deletions

diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index 308379b2d0b2..21079d1ca2aa 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -343,31 +343,25 @@ static int ovl_dentry_open(struct dentry *dentry, struct file *file,
         int err;
         struct path realpath;
         enum ovl_path_type type;
-        bool want_write = false;
 
         type = ovl_path_real(dentry, &realpath);
         if (ovl_open_need_copy_up(file->f_flags, type, realpath.dentry)) {
-                want_write = true;
                 err = ovl_want_write(dentry);
                 if (err)
-                        goto out;
+                        return err;
 
                 if (file->f_flags & O_TRUNC)
                         err = ovl_copy_up_last(dentry, NULL, true);
                 else
                         err = ovl_copy_up(dentry);
+                ovl_drop_write(dentry);
                 if (err)
-                        goto out_drop_write;
+                        return err;
 
                 ovl_path_upper(dentry, &realpath);
         }
 
-        err = vfs_open(&realpath, file, cred);
-out_drop_write:
-        if (want_write)
-                ovl_drop_write(dentry);
-out:
-        return err;
+        return vfs_open(&realpath, file, cred);
 }
 
 static const struct inode_operations ovl_file_inode_operations = {