Btrfs: fix btrfs page_mkwrite to return locked page

This closes a whole where the page may be written before the page_mkwrite caller has a chance to dirty it (thanks to Nick Piggin) Signed-off-by: Chris Mason <[email protected]>
tiwai · Sep 11, 2009 · 50a9b21 · 50a9b21
1 parent a1ed835
commit 50a9b21
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
@@ -4552,11 +4552,14 @@ int btrfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
 	}
 	ClearPageChecked(page);
 	set_page_dirty(page);
+	SetPageUptodate(page);
 
 	BTRFS_I(inode)->last_trans = root->fs_info->generation + 1;
 	unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
 
 out_unlock:
+	if (!ret)
+		return VM_FAULT_LOCKED;
 	unlock_page(page);
 out:
 	return ret;