From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) 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 shortcircuit=no autolearn=ham autolearn_force=no version=3.4.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id DCF5C1F404 for ; Wed, 12 Sep 2018 04:29:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725966AbeILJcT (ORCPT ); Wed, 12 Sep 2018 05:32:19 -0400 Received: from cloud.peff.net ([104.130.231.41]:46670 "HELO cloud.peff.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1725740AbeILJcT (ORCPT ); Wed, 12 Sep 2018 05:32:19 -0400 Received: (qmail 6159 invoked by uid 109); 12 Sep 2018 04:29:42 -0000 Received: from Unknown (HELO peff.net) (10.0.1.2) by cloud.peff.net (qpsmtpd/0.94) with SMTP; Wed, 12 Sep 2018 04:29:42 +0000 Authentication-Results: cloud.peff.net; auth=none Received: (qmail 24015 invoked by uid 111); 12 Sep 2018 04:29:54 -0000 Received: from Unknown (HELO sigill.intra.peff.net) (10.0.1.7) by peff.net (qpsmtpd/0.94) with (ECDHE-RSA-AES256-GCM-SHA384 encrypted) SMTP; Wed, 12 Sep 2018 00:29:54 -0400 Authentication-Results: peff.net; auth=none Received: by sigill.intra.peff.net (sSMTP sendmail emulation); Wed, 12 Sep 2018 00:29:39 -0400 Date: Wed, 12 Sep 2018 00:29:39 -0400 From: Jeff King To: Derrick Stolee Cc: "git@vger.kernel.org" , "sbeller@google.com" , "stolee@gmail.com" , "jonathantanmy@google.com" , "gitster@pobox.com" Subject: Re: [PATCH v2 17/18] commit-reach: make can_all_from_reach... linear Message-ID: <20180912042938.GA15876@sigill.intra.peff.net> References: <20180720163227.105950-1-dstolee@microsoft.com> <20180720163227.105950-18-dstolee@microsoft.com> <20180912041425.GA10472@sigill.intra.peff.net> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20180912041425.GA10472@sigill.intra.peff.net> Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Wed, Sep 12, 2018 at 12:14:25AM -0400, Jeff King wrote: > > + ALLOC_ARRAY(list, from->nr); > > for (i = 0; i < from->nr; i++) { > > - struct object *from_one = from->objects[i].item; > > + list[i] = (struct commit *)from->objects[i].item; > > Some of the objects in my array are not commits, but rather tags, so > this is a bogus cast. > > You can see that the original code peeled them and threw away > non-commits: > > > > > - if (from_one->flags & assign_flag) > > - continue; > > - from_one = deref_tag(the_repository, from_one, "a from object", 0); > > - if (!from_one || from_one->type != OBJ_COMMIT) { > > - /* no way to tell if this is reachable by > > - * looking at the ancestry chain alone, so > > - * leave a note to ourselves not to worry about > > - * this object anymore. > > - */ > > - from->objects[i].item->flags |= assign_flag; > > - continue; > > - } > > So presumably we'd need to do something similar. This patch seems to fix it for me. It's more or less a reversion of the hunk above, though I didn't dig into whether I'm violating some other assumption in your new code. I think this function leaks "list" both from the location I noted here, as well as from normal exit --- commit-reach.c | 25 ++++++++++++++++++------- 1 file changed, 18 insertions(+), 7 deletions(-) diff --git a/commit-reach.c b/commit-reach.c index 622eeb313d..abe90a2f55 100644 --- a/commit-reach.c +++ b/commit-reach.c @@ -547,20 +547,31 @@ int can_all_from_reach_with_flag(struct object_array *from, { struct commit **list = NULL; int i; + int nr_commits; int result = 1; ALLOC_ARRAY(list, from->nr); + nr_commits = 0; for (i = 0; i < from->nr; i++) { - list[i] = (struct commit *)from->objects[i].item; + struct object *from_one = from->objects[i].item; - if (parse_commit(list[i]) || - list[i]->generation < min_generation) - return 0; + from_one = deref_tag(the_repository, from_one, + "a from object", 0); + if (!from_one || from_one->type != OBJ_COMMIT) { + from->objects[i].item->flags |= assign_flag; + continue; + } + + list[nr_commits] = (struct commit *)from_one; + if (parse_commit(list[nr_commits]) || + list[nr_commits]->generation < min_generation) + return 0; /* is this a leak? */ + nr_commits++; } - QSORT(list, from->nr, compare_commits_by_gen); + QSORT(list, nr_commits, compare_commits_by_gen); - for (i = 0; i < from->nr; i++) { + for (i = 0; i < nr_commits; i++) { /* DFS from list[i] */ struct commit_list *stack = NULL; @@ -603,7 +614,7 @@ int can_all_from_reach_with_flag(struct object_array *from, } cleanup: - for (i = 0; i < from->nr; i++) { + for (i = 0; i < nr_commits; i++) { clear_commit_marks(list[i], RESULT); clear_commit_marks(list[i], assign_flag); } -- 2.19.0.600.ga229f7d059