From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4D229C433EF for ; Mon, 25 Apr 2022 18:11:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244249AbiDYSOk (ORCPT ); Mon, 25 Apr 2022 14:14:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54022 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236032AbiDYSOh (ORCPT ); Mon, 25 Apr 2022 14:14:37 -0400 Received: from mail-lf1-x12c.google.com (mail-lf1-x12c.google.com [IPv6:2a00:1450:4864:20::12c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9BA7911115E for ; Mon, 25 Apr 2022 11:11:31 -0700 (PDT) Received: by mail-lf1-x12c.google.com with SMTP id g19so27680917lfv.2 for ; Mon, 25 Apr 2022 11:11:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=mgZPcLi8Qc/FYo24I5Ui5ng4v5S2bS11j/TNA42dNdI=; b=AyTemggbe9yNeY3RXNoqcAc/M7mfZVWIDn0MNHEfheqaKT2mcwlb1VrhXvL8uuTyWP CNpuA7a0bg5jbWSiYl+aSOaGguqQA+9lY1Fqi7X4ipyhhZBkLDx7aYGS9i92fZTJ7olj bAGHOsvS2m1+Iwe/cjKA6S/ZrJVP0VywU2AmgY0M5byGjlTdfWSXKWgPtQIel65podM8 JRrSuaXT2mgZyZ+OaamNgbFGvPaL0qZpMz5kIc6MnOC6tqpZuikPOsgHwpYlHsnrAfUE JtHEtd/MgNB6te4d8uiGz6w4z8KqV2ijeLHQB9eHKFt4iwRMhm5xLJNutC1Z1Et2HDAO GHKQ== 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; bh=mgZPcLi8Qc/FYo24I5Ui5ng4v5S2bS11j/TNA42dNdI=; b=rlTZFtsEtS5ptC4knKna+oIkL1azZbfF6lwQJ/HlzP4d2mV96Dt2J4pS5C87M8Lx/h dQMHhgoObMEXgBv2C45I9rRo4Ok9lfpb6IZmF6erXrsisrTGzHMncLsvlYrQRM6OiQ/z qPcJrBJb6i9xzdbERwjQf+pv9W90CR6xuowjVnoYb6T56lxrXUew0koAFH8jeJRGSJNJ ylZ3tnKhy/iF9BsfPRnQeRKt4Z1uZydC6LeQ2FvlHBo84/ZE3OjVgAsETZnWb7RVlL3u 7QW5phDUIFZ7IS4HhSN1EKYBkzjCHNSFeXtcwBOI5lhsHjF7wmF5z9KtjXKqFFPoD6H+ 9b9A== X-Gm-Message-State: AOAM5330JVrJdjIHtU7y33yHHmB/fWlJm0mY+/2D4oaYwFMK2r/hA4I6 Gcl96NdIbDNrwOdZsyjLok6GLoGqmSWk6v1wxGxKcUR2ffA= X-Google-Smtp-Source: ABdhPJxiQBayWivPSmwOm7iRe8+oFmRUHaUcR4YG3TbfL0hdALVJpOAd5m2+OrL9AulLRlq44PjBgHKNC39atXKgnfg= X-Received: by 2002:a05:6512:1d1:b0:471:f63a:b182 with SMTP id f17-20020a05651201d100b00471f63ab182mr9720569lfp.392.1650910289712; Mon, 25 Apr 2022 11:11:29 -0700 (PDT) MIME-Version: 1.0 References: <20220424190811.1678416-1-masahiroy@kernel.org> <20220424190811.1678416-2-masahiroy@kernel.org> In-Reply-To: <20220424190811.1678416-2-masahiroy@kernel.org> From: Nick Desaulniers Date: Mon, 25 Apr 2022 11:11:17 -0700 Message-ID: Subject: Re: [PATCH 01/27] modpost: use snprintf() instead of sprintf() for safety To: Masahiro Yamada Cc: linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, Michal Marek Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Apr 24, 2022 at 12:09 PM Masahiro Yamada wrote: > > Use snprintf() to avoid the potential buffer overflow, and also > check the return value to detect the too long path. > > Signed-off-by: Masahiro Yamada Thanks for the patch! Reviewed-by: Nick Desaulniers > --- > > scripts/mod/modpost.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c > index 522d5249d196..141370ebbfd3 100644 > --- a/scripts/mod/modpost.c > +++ b/scripts/mod/modpost.c > @@ -2560,6 +2560,7 @@ int main(int argc, char **argv) > > for (mod = modules; mod; mod = mod->next) { > char fname[PATH_MAX]; > + int ret; > > if (mod->is_vmlinux || mod->from_dump) > continue; > @@ -2578,7 +2579,12 @@ int main(int argc, char **argv) > add_moddevtable(&buf, mod); > add_srcversion(&buf, mod); > > - sprintf(fname, "%s.mod.c", mod->name); > + ret = snprintf(fname, sizeof(fname), "%s.mod.c", mod->name); > + if (ret >= sizeof(fname)) { > + error("%s: too long path was truncated\n", fname); > + continue; > + } > + > write_if_changed(&buf, fname); > } > > -- > 2.32.0 > -- Thanks, ~Nick Desaulniers