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: AS53758 23.128.96.0/24 X-Spam-Status: No, score=-3.7 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED, SPF_HELO_PASS,SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by dcvr.yhbt.net (Postfix) with ESMTP id 9F7A91F8C8 for ; Wed, 6 Oct 2021 15:59:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231955AbhJFQAv (ORCPT ); Wed, 6 Oct 2021 12:00:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58788 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230101AbhJFQAu (ORCPT ); Wed, 6 Oct 2021 12:00:50 -0400 Received: from mail-ed1-x534.google.com (mail-ed1-x534.google.com [IPv6:2a00:1450:4864:20::534]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9AE19C061746 for ; Wed, 6 Oct 2021 08:58:57 -0700 (PDT) Received: by mail-ed1-x534.google.com with SMTP id z20so11579975edc.13 for ; Wed, 06 Oct 2021 08:58:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=UrrodMsqw5qaXZieFFAut0nBJMyeHj5kamInnvkT0Cg=; b=IxVqfgpYGp6xy0P13937Z2tMIw5uFrkippoTFx0m9gWsZ5MszVUMMME7R30rMlQtyu B2xHCMJUa/CqeAl5ZCKdlWEht8Q1xtragqBMxYNbT3ojKQYdAbv2HvE6Izos5KgaeXa6 Hw9qB2jhL2PvMldSDmtOk5+LyQkKDr4gMHLc0dwh3/7a/ooS0HQVxMrrNo6b/0L5fvHh k36LUGD6sL5rpFWCLVbCkOAaMmnBNkRZBy6+qsn3GBTWzEfFBQD3683Vfs/N6sMyoZ5W uJcw/q8MWT1gWEAYlUABRXO62VW/+7wwpxtxxRZETE2FPZT8Pb78uHJ0wdTTEo4pVAf3 mAaQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=UrrodMsqw5qaXZieFFAut0nBJMyeHj5kamInnvkT0Cg=; b=k1s8csK9/LwZCyzXU2Y7I90GJ1rMCSNiZupfZdoZgs9vi5sbYFv8MJMXgwFFUhD453 FwrrUid9HbZFI1yC3Rdw/sAmTdU1mbA58NSWIeQc7nablfevR4yMlCkJBm9kOo2XUmvi GRQCVqlhsSnSwu+xQgiWMfdASGUiVlRIw/RJEiQ8Kvh4Vua/rNvagwTRtkhZj9t7613x K1TCDJqGGJOAfGgdb7lm2KrlK5LzIk2Pm2vsRewUKeR7lcSnXM8yTVHYAtjgIDCrgU30 wbYPHPb2r+PRGOuTO5JFeLnfW7pYblXSk1YG8T5CTL83IUVhPREK/VYZG0R1HjfbFnYM /txw== X-Gm-Message-State: AOAM5321Vq8gl60Grjr4DghXQkMaJI1Qu4HeKtDuuG8OBNCFVGTGaZ+x 9El0PJrArA2ZIL0w7qnFLSI0P/WdOsEEL8/TVQSlRjzZbIg= X-Google-Smtp-Source: ABdhPJwsSo9CYpxsWPwXr4EfDcnI9lzfdkbnmUApQn02xyuaIG0zmtvtsTEB/hk9TeSrmFBHO79z6butooSqYDBiy9c= X-Received: by 2002:a05:6402:7d0:: with SMTP id u16mr10534722edy.62.1633535936122; Wed, 06 Oct 2021 08:58:56 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Elijah Newren Date: Wed, 6 Oct 2021 08:58:44 -0700 Message-ID: Subject: Re: [PATCH 1/2] unpack-trees: don't leak memory in verify_clean_subdirectory() To: =?UTF-8?B?w4Z2YXIgQXJuZmrDtnLDsCBCamFybWFzb24=?= Cc: Git Mailing List , Junio C Hamano , =?UTF-8?B?Tmd1eeG7hW4gVGjDoWkgTmfhu41jIER1eQ==?= , =?UTF-8?Q?Martin_=C3=85gren?= , Andrzej Hunt , Jeff King Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Wed, Oct 6, 2021 at 2:40 AM =C3=86var Arnfj=C3=B6r=C3=B0 Bjarmason wrote: > > Fix two different but related memory leaks in > verify_clean_subdirectory(). We leaked both the "pathbuf" if > read_directory() returned non-zero, and we never cleaned up our own > "struct dir_struct" either. > > * "pathbuf": When the read_directory() call followed by the > free(pathbuf) was added in c81935348be (Fix switching to a branch > with D/F when current branch has file D., 2007-03-15) we didn't > bother to free() before we called die(). > > But when this code was later libified in 203a2fe1170 (Allow callers > of unpack_trees() to handle failure, 2008-02-07) we started to leak > as we returned data to the caller. This fixes that memory leak, > which can be observed under SANITIZE=3Dleak with e.g. the > "t1001-read-tree-m-2way.sh" test. > > * "struct dir_struct": We've leaked the dir_struct ever since this > code was added back in c81935348be. > > When that commit was written there wasn't an equivalent of > dir_clear(). Since it was added in 270be816049 (dir.c: provide > clear_directory() for reclaiming dir_struct memory, 2013-01-06) > we've omitted freeing the memory allocated here. > > This memory leak could also be observed under SANITIZE=3Dleak and the > "t1001-read-tree-m-2way.sh" test. > > This makes all the test in "t1001-read-tree-m-2way.sh" pass under > "GIT_TEST_PASSING_SANITIZE_LEAK=3Dtrue", we'd previously die in tests > 25, 26 & 28. > > Signed-off-by: =C3=86var Arnfj=C3=B6r=C3=B0 Bjarmason > --- > t/t1001-read-tree-m-2way.sh | 2 ++ > unpack-trees.c | 3 ++- > 2 files changed, 4 insertions(+), 1 deletion(-) > > diff --git a/t/t1001-read-tree-m-2way.sh b/t/t1001-read-tree-m-2way.sh > index 1057a96b249..d1115528cb9 100755 > --- a/t/t1001-read-tree-m-2way.sh > +++ b/t/t1001-read-tree-m-2way.sh > @@ -20,6 +20,8 @@ In the test, these paths are used: > rezrov - in H, deleted in M > yomin - not in H or M > ' > + > +TEST_PASSES_SANITIZE_LEAK=3Dtrue > . ./test-lib.sh > . "$TEST_DIRECTORY"/lib-read-tree.sh > > diff --git a/unpack-trees.c b/unpack-trees.c > index a7e1712d236..89ca95ce90b 100644 > --- a/unpack-trees.c > +++ b/unpack-trees.c > @@ -2156,9 +2156,10 @@ static int verify_clean_subdirectory(const struct = cache_entry *ce, > if (o->dir) > d.exclude_per_dir =3D o->dir->exclude_per_dir; > i =3D read_directory(&d, o->src_index, pathbuf, namelen+1, NULL); > + dir_clear(&d); > + free(pathbuf); > if (i) > return add_rejected_path(o, ERROR_NOT_UPTODATE_DIR, ce->n= ame); > - free(pathbuf); > return cnt; > } > > -- > 2.33.0.1441.gbbcdb4c3c66 Nicely explained; and nice clean patch.