Re: [PATCH 06/10] cachefiles, erofs: Fix NULL deref in when cachefiles is not doing ondemand-mode

[David Howells <dhowells@redhat.com>]

Jingbo Xu <jefflexu@linux.alibaba.com> wrote:

> > -	ret = cachefiles_ondemand_init_object(object);
> > -	if (ret < 0)
> > -		goto err_unuse;
> > +	if (object->ondemand) {
> > +		ret = cachefiles_ondemand_init_object(object);
> > +		if (ret < 0)
> > +			goto err_unuse;
> > +	}
> 
> I'm not sure if object->ondemand shall be checked by the caller or
> inside cachefiles_ondemand_init_object(), as
> cachefiles_ondemand_clean_object() is also called without checking
> object->ondemand. cachefiles_ondemand_clean_object() won't trigger the
> NULL oops as the called cachefiles_ondemand_send_req() will actually
> checks that.

Meh.  The above doesn't actually build if CONFIG_CACHEFILES_ONDEMAND=N.  I
think I have to push the check down into cachefiles_ondemand_init_object()
instead.

David