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=-3.6 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_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 F28F51F403 for ; Mon, 11 Jun 2018 15:03:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754014AbeFKPDD (ORCPT ); Mon, 11 Jun 2018 11:03:03 -0400 Received: from mail-ua0-f194.google.com ([209.85.217.194]:35531 "EHLO mail-ua0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751991AbeFKPDC (ORCPT ); Mon, 11 Jun 2018 11:03:02 -0400 Received: by mail-ua0-f194.google.com with SMTP id s13-v6so10296593uad.2 for ; Mon, 11 Jun 2018 08:03:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=gbvGA20C107ykdcQh7KUhAdMmgsaBwejlGFQnBTa9Rc=; b=fUwsRId4faISVHuLScH7W2wqUhmKDfSggDY/AcmHTc1ESuF3ZNd4oIq1XGmEGbJxbs sBpdm7GlckWubkiBkPnNHWPgGvvD2rlmIH2947RhGAGlI1XM/BdRF6+Us2elmhTbSYqe ObvBjgbvsgigoPfdQ2IvYZ1JQV3Y7VbIraqAV83cZzNW1Log2h+fnmiKHwkSkzsNZBPa NMYW66tGv66iXNgDfKITE0j8ol1A7rTbD+Gs6xxTYa5oVgJ3YCCJkfK4WuO9bsRPEtmd ER7w4cmQ4eoW7dQnkJgvWgtxD2KJkKyZoIj1hdP2qTyWOgtFfepjOlaItGaDsuNWl2FZ kZDg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=gbvGA20C107ykdcQh7KUhAdMmgsaBwejlGFQnBTa9Rc=; b=Rhqh653Y1IkUfaFhS+dz5oJ93P9bGspIuATI9Kxx/D+N0SSc0hvb9yJ6YBww483Qtp ak7g4GsSeRk644/KFziK111hwiq/FxPvehQCiRl+lwGJSka0YOkzwcneDosgWEiSHEF4 XcBkkNm5dOA74TK/R+nLqQbkHXQU8Np1ZaDcYBD5CASBade8JRsd9bVq+J+mpbplHLke xamzaP6vDFSa9QaLnmG4XbNS41OHKLxnUUcmEeqMW+01Fslqd9+/RKmgPIy38ITkrQXh FZiVYcy8JAGJogmMK1YFYrpg8JhHN9Ps2IG4TgwtZeSx1KmrLYsLY1l6KkdvMAaoJTp+ jy5A== X-Gm-Message-State: APt69E12gEeK6T23uoBeP340Y1fpks6IA+mqTDTlsfkDzD6hHAfMZ4K1 NpVZs+miR4B7NNAFwju5Ku5fZehVr6utY71LoVI= X-Google-Smtp-Source: ADUXVKINU7h1+tXHwpZ+REUJFpUiS1Ogsvkg9iE08HgXSZOWIuXBptp5pwFrlYdKeAvyf9kwGLnLwAC5WtYNyy83av0= X-Received: by 2002:ab0:1723:: with SMTP id j35-v6mr11701656uaf.154.1528729381423; Mon, 11 Jun 2018 08:03:01 -0700 (PDT) MIME-Version: 1.0 Received: by 2002:ab0:5f28:0:0:0:0:0 with HTTP; Mon, 11 Jun 2018 08:03:00 -0700 (PDT) In-Reply-To: <7d1237c7-5a83-d766-7d93-5f0d59166067@web.de> References: <20171110190550.27059-1-newren@gmail.com> <20171110190550.27059-25-newren@gmail.com> <7d1237c7-5a83-d766-7d93-5f0d59166067@web.de> From: Elijah Newren Date: Mon, 11 Jun 2018 08:03:00 -0700 Message-ID: Subject: Re: [PATCH 24/30] merge-recursive: Add computation of collisions due to dir rename & merging To: =?UTF-8?Q?Ren=C3=A9_Scharfe?= Cc: Git Mailing List , Junio C Hamano , Jeff King Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Sun, Jun 10, 2018 at 3:56 AM, Ren=C3=A9 Scharfe wrote: > Am 10.11.2017 um 20:05 schrieb Elijah Newren: >> +static struct dir_rename_entry *check_dir_renamed(const char *path, >> + struct hashmap *dir_rena= mes) { >> + char temp[PATH_MAX]; >> + char *end; >> + struct dir_rename_entry *entry; >> + >> + strcpy(temp, path); >> + while ((end =3D strrchr(temp, '/'))) { >> + *end =3D '\0'; >> + entry =3D dir_rename_find_entry(dir_renames, temp); >> + if (entry) >> + return entry; >> + } >> + return NULL; >> +} > > The value of PATH_MAX is platform-dependent, so it's easy to exceed when > doing cross-platform development. It's also not a hard limit on most > operating systems, not even on Windows. Further reading: > > https://insanecoding.blogspot.com/2007/11/pathmax-simply-isnt.html > > So using a fixed buffer is not a good idea, and writing to it without > checking is dangerous. Here's a fix: Thanks for the pointers, and for providing a fix. > -- >8 -- > Subject: [PATCH] merge-recursive: use xstrdup() instead of fixed buffer > > Paths can be longer than PATH_MAX. Avoid a buffer overrun in > check_dir_renamed() by using xstrdup() to make a private copy safely. > > Signed-off-by: Rene Scharfe > --- > merge-recursive.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/merge-recursive.c b/merge-recursive.c > index ac27abbd4c..db708176c5 100644 > --- a/merge-recursive.c > +++ b/merge-recursive.c > @@ -2211,18 +2211,18 @@ static struct hashmap *get_directory_renames(stru= ct diff_queue_struct *pairs, > static struct dir_rename_entry *check_dir_renamed(const char *path, > struct hashmap *dir_ren= ames) > { > - char temp[PATH_MAX]; > + char *temp =3D xstrdup(path); > char *end; > - struct dir_rename_entry *entry; > + struct dir_rename_entry *entry =3D NULL;; > > - strcpy(temp, path); > while ((end =3D strrchr(temp, '/'))) { > *end =3D '\0'; > entry =3D dir_rename_find_entry(dir_renames, temp); > if (entry) > - return entry; > + break; > } > - return NULL; > + free(temp); > + return entry; > } > > static void compute_collisions(struct hashmap *collisions, > -- > 2.17.1 Reviewed-by: Elijah Newren