long lower_namelen;
/* pathnames of lower and upper dirs, for show_options */
struct ovl_config config;
+ /* creds of process who forced instantiation of super block */
+ const struct cred *creator_cred;
};
struct ovl_dir_cache;
return inode && IS_WHITEOUT(inode);
}
+const struct cred *ovl_override_creds(struct super_block *sb)
+{
+ struct ovl_fs *ofs = sb->s_fs_info;
+
+ return override_creds(ofs->creator_cred);
+}
+
static bool ovl_is_opaquedir(struct dentry *dentry)
{
int res;
kfree(ufs->config.lowerdir);
kfree(ufs->config.upperdir);
kfree(ufs->config.workdir);
+ put_cred(ufs->creator_cred);
kfree(ufs);
}
/*
* Upper should support d_type, else whiteouts are visible.
* Given workdir and upper are on same fs, we can do
- * iterate_dir() on workdir.
+ * iterate_dir() on workdir. This check requires successful
+ * creation of workdir in previous step.
*/
- err = ovl_check_d_type_supported(&workpath);
- if (err < 0)
- goto out_put_workdir;
+ if (ufs->workdir) {
+ err = ovl_check_d_type_supported(&workpath);
+ if (err < 0)
+ goto out_put_workdir;
- if (!err) {
- pr_err("overlayfs: upper fs needs to support d_type.\n");
- err = -EINVAL;
- goto out_put_workdir;
+ /*
+ * We allowed this configuration and don't want to
+ * break users over kernel upgrade. So warn instead
+ * of erroring out.
+ */
+ if (!err)
+ pr_warn("overlayfs: upper fs needs to support d_type.\n");
}
}
else
sb->s_d_op = &ovl_dentry_operations;
+ ufs->creator_cred = prepare_creds();
+ if (!ufs->creator_cred)
+ goto out_put_lower_mnt;
+
err = -ENOMEM;
oe = ovl_alloc_entry(numlower);
if (!oe)
- goto out_put_lower_mnt;
+ goto out_put_cred;
root_dentry = d_make_root(ovl_new_inode(sb, S_IFDIR, oe));
if (!root_dentry)
out_free_oe:
kfree(oe);
+out_put_cred:
+ put_cred(ufs->creator_cred);
out_put_lower_mnt:
for (i = 0; i < ufs->numlower; i++)
mntput(ufs->lower_mnt[i]);