ovl: compare inodes

When checking for consistency in directory operations (unlink, rename,
etc.) match inodes not dentries.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
index fcfa7de12ad57299a2dbb45e8eb5ac08f336dc70..59e0dc9897fbb21c977d6e90ade93d052d279b9b 100644 (file)
--- a/fs/overlayfs/dir.c
+++ b/fs/overlayfs/dir.c
@@ -611,6 +611,11 @@ out:
        return err;
 }
 
+static bool ovl_matches_upper(struct dentry *dentry, struct dentry *upper)
+{
+       return d_inode(ovl_dentry_upper(dentry)) == d_inode(upper);
+}
+
 static int ovl_remove_and_whiteout(struct dentry *dentry, bool is_dir)
 {
        struct dentry *workdir = ovl_workdir(dentry);
@@ -646,7 +651,7 @@ static int ovl_remove_and_whiteout(struct dentry *dentry, bool is_dir)
        err = -ESTALE;
        if ((opaquedir && upper != opaquedir) ||
            (!opaquedir && ovl_dentry_upper(dentry) &&
-            upper != ovl_dentry_upper(dentry))) {
+            !ovl_matches_upper(dentry, upper))) {
                goto out_dput_upper;
        }
 
@@ -707,7 +712,7 @@ static int ovl_remove_upper(struct dentry *dentry, bool is_dir)
 
        err = -ESTALE;
        if ((opaquedir && upper != opaquedir) ||
-           (!opaquedir && upper != ovl_dentry_upper(dentry)))
+           (!opaquedir && !ovl_matches_upper(dentry, upper)))
                goto out_dput_upper;
 
        if (is_dir)
@@ -985,7 +990,7 @@ static int ovl_rename(struct inode *olddir, struct dentry *old,
                goto out_unlock;
 
        err = -ESTALE;
-       if (olddentry != ovl_dentry_upper(old))
+       if (!ovl_matches_upper(old, olddentry))
                goto out_dput_old;
 
        newdentry = lookup_one_len(new->d_name.name, new_upperdir,
@@ -1003,7 +1008,7 @@ static int ovl_rename(struct inode *olddir, struct dentry *old,
                        if (newdentry != opaquedir)
                                goto out_dput;
                } else {
-                       if (newdentry != ovl_dentry_upper(new))
+                       if (!ovl_matches_upper(new, newdentry))
                                goto out_dput;
                }
        } else {