From patchwork Mon May 23 16:46:24 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 12859274 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 36EBCC433EF for ; Mon, 23 May 2022 16:48:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239173AbiEWQsh (ORCPT ); Mon, 23 May 2022 12:48:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58246 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239148AbiEWQsf (ORCPT ); Mon, 23 May 2022 12:48:35 -0400 Received: from conuserg-09.nifty.com (conuserg-09.nifty.com [210.131.2.76]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D7EE265D3B; Mon, 23 May 2022 09:48:29 -0700 (PDT) Received: from grover.sesame (133-32-177-133.west.xps.vectant.ne.jp [133.32.177.133]) (authenticated) by conuserg-09.nifty.com with ESMTP id 24NGlJD2027017; Tue, 24 May 2022 01:47:21 +0900 DKIM-Filter: OpenDKIM Filter v2.10.3 conuserg-09.nifty.com 24NGlJD2027017 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nifty.com; s=dec2015msa; t=1653324441; bh=9VkSZyqvjBg0Nd6+4A0acMuL4QkugOVgV61qsiUyjxo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vgcW+5UuTOCoZwOd3bihOfnGjtXB0QM4j45PjQOSAxwc2OfU+cU4BKu8m1mcGU0Tt UW84tfeMdGyzBU20U2VPKrDJ2GDT+TQPbASRau+UGWNZvZGAA839PUFhnTaVVI7cOb M5xYyyZj810ta78qYLm+HeA35myOccYP0Td0poM1nu0veamtIHDVgBFpMi4M7s727J g+H8KCzW6oYV08Yr42eueCpMJs9I5zj8AW4I0BgZVbkiyU8b4OQ7NHqadsH7glN6GO GZCCYorECD94/GDTs5bgSKpyiXcCjIFjIkRJLeftSfBv8SIkw+JJkNv8tie11jL1d0 GT9pw4Y8AAMYA== X-Nifty-SrcIP: [133.32.177.133] From: Masahiro Yamada To: linux-kbuild@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Masahiro Yamada , Michal Marek , Nick Desaulniers Subject: [PATCH 3/5] modpost: simplify mod->name allocation Date: Tue, 24 May 2022 01:46:24 +0900 Message-Id: <20220523164626.858340-3-masahiroy@kernel.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220523164626.858340-1-masahiroy@kernel.org> References: <20220523164626.858340-1-masahiroy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org mod->name is set to the ELF filename with the suffix ".o" stripped. The current code calls strdup() and free() to manipulate the string, but a simpler approach is to pass new_module() with the name length subtracted by 2. Also, check if the passed filename ends with ".o" before stripping it. The current code blindly chops the suffix tmp[strlen(tmp) - 2] = '\0' but it will cause buffer under-run if strlen(tmp) < 2; Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers --- scripts/mod/modpost.c | 25 ++++++++++++------------- 1 file changed, 12 insertions(+), 13 deletions(-) diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 843c64eebe8b..77c315dea1a3 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -172,11 +172,11 @@ static struct module *find_module(const char *modname) return NULL; } -static struct module *new_module(const char *modname) +static struct module *new_module(const char *name, size_t namelen) { struct module *mod; - mod = NOFAIL(malloc(sizeof(*mod) + strlen(modname) + 1)); + mod = NOFAIL(malloc(sizeof(*mod) + namelen + 1)); memset(mod, 0, sizeof(*mod)); INIT_LIST_HEAD(&mod->exported_symbols); @@ -184,8 +184,9 @@ static struct module *new_module(const char *modname) INIT_LIST_HEAD(&mod->missing_namespaces); INIT_LIST_HEAD(&mod->imported_namespaces); - strcpy(mod->name, modname); - mod->is_vmlinux = (strcmp(modname, "vmlinux") == 0); + memcpy(mod->name, name, namelen); + mod->name[namelen] = '\0'; + mod->is_vmlinux = (strcmp(mod->name, "vmlinux") == 0); /* * Set mod->is_gpl_compatible to true by default. If MODULE_LICENSE() @@ -2022,16 +2023,14 @@ static void read_symbols(const char *modname) if (!parse_elf(&info, modname)) return; - { - char *tmp; - - /* strip trailing .o */ - tmp = NOFAIL(strdup(modname)); - tmp[strlen(tmp) - 2] = '\0'; - mod = new_module(tmp); - free(tmp); + if (!strends(modname, ".o")) { + error("%s: filename must be suffixed with .o\n", modname); + return; } + /* strip trailing .o */ + mod = new_module(modname, strlen(modname) - strlen(".o")); + if (!mod->is_vmlinux) { license = get_modinfo(&info, "license"); if (!license) @@ -2493,7 +2492,7 @@ static void read_dump(const char *fname) mod = find_module(modname); if (!mod) { - mod = new_module(modname); + mod = new_module(modname, strlen(modname)); mod->from_dump = true; } s = sym_add_exported(symname, mod, gpl_only);