From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-3.9 required=3.0 tests=AWL,BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, RCVD_IN_MSPIKE_H3,RCVD_IN_MSPIKE_WL,SPF_HELO_NONE,SPF_NONE shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id E66451F45E for ; Sat, 15 Feb 2020 06:46:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725882AbgBOGqz (ORCPT ); Sat, 15 Feb 2020 01:46:55 -0500 Received: from cloud.peff.net ([104.130.231.41]:44130 "HELO cloud.peff.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1725822AbgBOGqz (ORCPT ); Sat, 15 Feb 2020 01:46:55 -0500 Received: (qmail 25647 invoked by uid 109); 15 Feb 2020 06:46:55 -0000 Received: from Unknown (HELO peff.net) (10.0.1.2) by cloud.peff.net (qpsmtpd/0.94) with SMTP; Sat, 15 Feb 2020 06:46:55 +0000 Authentication-Results: cloud.peff.net; auth=none Received: (qmail 26761 invoked by uid 111); 15 Feb 2020 06:55:52 -0000 Received: from coredump.intra.peff.net (HELO sigill.intra.peff.net) (10.0.0.2) by peff.net (qpsmtpd/0.94) with (TLS_AES_256_GCM_SHA384 encrypted) ESMTPS; Sat, 15 Feb 2020 01:55:52 -0500 Authentication-Results: peff.net; auth=none Date: Sat, 15 Feb 2020 01:46:54 -0500 From: Jeff King To: Taylor Blau Cc: git@vger.kernel.org, Junio C Hamano Subject: Re: [PATCH v2 02/15] pack-bitmap: fix leak of haves/wants object lists Message-ID: <20200215064654.GA1633703@coredump.intra.peff.net> References: <20200214182147.GA654525@coredump.intra.peff.net> <20200214182211.GB150965@coredump.intra.peff.net> <20200215001552.GE11400@syl.local> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20200215001552.GE11400@syl.local> Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Fri, Feb 14, 2020 at 04:15:52PM -0800, Taylor Blau wrote: > > +void object_list_free(struct object_list **list) > > +{ > > + while (*list) { > > + struct object_list *p = *list; > > + *list = p->next; > > + free(p); > > + } > > +} > > Hmm. I was going to write a comment saying more-or-less, "I think I'm > nitpicking here, but I'm not crazy about this as a 'while' loop". But, > when I wrote this as a 'for' loop instead, I wrote a use-after-free, and > then when I rid the code of that, it wasn't any more readable than the > version above. Yep, linked lists are deceptive that way. This _could_ be converted to use the generic list.h macros. Or better still, we could probably ditch it entirely in favor of an object_array. But I'd prefer to do that separately, if at all. -Peff