ovl: handle rename when upper doesn't support xattr
authorAmir Goldstein <amir73il@gmail.com>
Tue, 16 May 2017 21:12:41 +0000 (00:12 +0300)
committerMiklos Szeredi <mszeredi@redhat.com>
Fri, 19 May 2017 07:33:49 +0000 (09:33 +0200)
On failure to set opaque/redirect xattr on rename, skip setting xattr and
return -EXDEV.

On failure to set opaque xattr when creating a new directory, -EIO is
returned instead of -EOPNOTSUPP.

Any failure to set those xattr will be recorded in super block and
then setting any xattr on upper won't be attempted again.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
fs/overlayfs/dir.c
fs/overlayfs/overlayfs.h
fs/overlayfs/util.c

index 723b98b9069876d1656b74735dabcaf01484e26d..80e0e202a346ed4b7bfd4078b469b6558fc47c3d 100644 (file)
@@ -127,17 +127,28 @@ int ovl_create_real(struct inode *dir, struct dentry *newdentry,
        return err;
 }
 
-static int ovl_set_opaque(struct dentry *dentry, struct dentry *upperdentry)
+static int ovl_set_opaque_xerr(struct dentry *dentry, struct dentry *upper,
+                              int xerr)
 {
        int err;
 
-       err = ovl_do_setxattr(upperdentry, OVL_XATTR_OPAQUE, "y", 1, 0);
+       err = ovl_check_setxattr(dentry, upper, OVL_XATTR_OPAQUE, "y", 1, xerr);
        if (!err)
                ovl_dentry_set_opaque(dentry);
 
        return err;
 }
 
+static int ovl_set_opaque(struct dentry *dentry, struct dentry *upperdentry)
+{
+       /*
+        * Fail with -EIO when trying to create opaque dir and upper doesn't
+        * support xattrs. ovl_rename() calls ovl_set_opaque_xerr(-EXDEV) to
+        * return a specific error for noxattr case.
+        */
+       return ovl_set_opaque_xerr(dentry, upperdentry, -EIO);
+}
+
 /* Common operations required to be done after creation of file on upper */
 static void ovl_instantiate(struct dentry *dentry, struct inode *inode,
                            struct dentry *newdentry, bool hardlink)
@@ -846,18 +857,16 @@ static int ovl_set_redirect(struct dentry *dentry, bool samedir)
        if (IS_ERR(redirect))
                return PTR_ERR(redirect);
 
-       err = ovl_do_setxattr(ovl_dentry_upper(dentry), OVL_XATTR_REDIRECT,
-                             redirect, strlen(redirect), 0);
+       err = ovl_check_setxattr(dentry, ovl_dentry_upper(dentry),
+                                OVL_XATTR_REDIRECT,
+                                redirect, strlen(redirect), -EXDEV);
        if (!err) {
                spin_lock(&dentry->d_lock);
                ovl_dentry_set_redirect(dentry, redirect);
                spin_unlock(&dentry->d_lock);
        } else {
                kfree(redirect);
-               if (err == -EOPNOTSUPP)
-                       ovl_clear_redirect_dir(dentry->d_sb);
-               else
-                       pr_warn_ratelimited("overlay: failed to set redirect (%i)\n", err);
+               pr_warn_ratelimited("overlay: failed to set redirect (%i)\n", err);
                /* Fall back to userspace copy-up */
                err = -EXDEV;
        }
@@ -992,7 +1001,7 @@ static int ovl_rename(struct inode *olddir, struct dentry *old,
                if (ovl_type_merge_or_lower(old))
                        err = ovl_set_redirect(old, samedir);
                else if (!old_opaque && ovl_type_merge(new->d_parent))
-                       err = ovl_set_opaque(old, olddentry);
+                       err = ovl_set_opaque_xerr(old, olddentry, -EXDEV);
                if (err)
                        goto out_dput;
        }
@@ -1000,7 +1009,7 @@ static int ovl_rename(struct inode *olddir, struct dentry *old,
                if (ovl_type_merge_or_lower(new))
                        err = ovl_set_redirect(new, samedir);
                else if (!new_opaque && ovl_type_merge(old->d_parent))
-                       err = ovl_set_opaque(new, newdentry);
+                       err = ovl_set_opaque_xerr(new, newdentry, -EXDEV);
                if (err)
                        goto out_dput;
        }
index ce7c3aba61e46fbc2745665c7673cba8b473b4ba..505b18b563303390900b756f99e2a7151a2d5646 100644 (file)
@@ -206,7 +206,6 @@ bool ovl_dentry_is_opaque(struct dentry *dentry);
 bool ovl_dentry_is_whiteout(struct dentry *dentry);
 void ovl_dentry_set_opaque(struct dentry *dentry);
 bool ovl_redirect_dir(struct super_block *sb);
-void ovl_clear_redirect_dir(struct super_block *sb);
 const char *ovl_dentry_get_redirect(struct dentry *dentry);
 void ovl_dentry_set_redirect(struct dentry *dentry, const char *redirect);
 void ovl_dentry_update(struct dentry *dentry, struct dentry *upperdentry);
index b5a0dc36ee968c151a5a276a22c21c7e33c9684f..4d541a8d0834516ac8d85478cf32a8d3c327f1f4 100644 (file)
@@ -191,14 +191,7 @@ bool ovl_redirect_dir(struct super_block *sb)
 {
        struct ovl_fs *ofs = sb->s_fs_info;
 
-       return ofs->config.redirect_dir;
-}
-
-void ovl_clear_redirect_dir(struct super_block *sb)
-{
-       struct ovl_fs *ofs = sb->s_fs_info;
-
-       ofs->config.redirect_dir = false;
+       return ofs->config.redirect_dir && !ofs->noxattr;
 }
 
 const char *ovl_dentry_get_redirect(struct dentry *dentry)