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 X-Spam-Level: X-Spam-Status: No, score=-10.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7C3FFC433FC for ; Tue, 14 Jul 2020 19:12:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 545C2221ED for ; Tue, 14 Jul 2020 19:12:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594753933; bh=lHoFsJHhdG2dbnh2ce7yjRas4/oHkqce+YQiHAMMOGo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=LztuZNtWeLTzVxdaGLaOSQn4l/nJv3CpxeUhNbSL2Nh5GdiDXb7Jbs5GY/N+5Lil+ M6BLlMyze0Gt4DawaG4RalRFHHdU10bEHTabmA4qrf2k8WDyB9b0hRU6JjGdTUIpHV iY0ibazxOXMV87NhewqnsGBmvbxI8kddl7xwYQDI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730474AbgGNTML (ORCPT ); Tue, 14 Jul 2020 15:12:11 -0400 Received: from mail.kernel.org ([198.145.29.99]:42730 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729738AbgGNSrf (ORCPT ); Tue, 14 Jul 2020 14:47:35 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 788DB22AAE; Tue, 14 Jul 2020 18:47:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594752455; bh=lHoFsJHhdG2dbnh2ce7yjRas4/oHkqce+YQiHAMMOGo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bODN6zQpyX9qAwvAUsXaFLcpd040evA0KX1PTpTIW34ePsD+VSlh+46Yco7zCwXYz 8FBQ6lXpDhahAcu/1RQFkMLJYIEJ6rghfV08UtjjM713fi9LMGmkeiVBJ5PdXnywVp /dn5+5+wJwXkdfO4ofa9kTCW/8SSy+XdwwmLdu3w= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jessica Yu , Kees Cook Subject: [PATCH 4.19 48/58] module: Refactor section attr into bin attribute Date: Tue, 14 Jul 2020 20:44:21 +0200 Message-Id: <20200714184058.548988651@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714184056.149119318@linuxfoundation.org> References: <20200714184056.149119318@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Kees Cook commit ed66f991bb19d94cae5d38f77de81f96aac7813f upstream. In order to gain access to the open file's f_cred for kallsym visibility permission checks, refactor the module section attributes to use the bin_attribute instead of attribute interface. Additionally removes the redundant "name" struct member. Cc: stable@vger.kernel.org Reviewed-by: Greg Kroah-Hartman Tested-by: Jessica Yu Acked-by: Jessica Yu Signed-off-by: Kees Cook Signed-off-by: Greg Kroah-Hartman --- kernel/module.c | 45 ++++++++++++++++++++++++--------------------- 1 file changed, 24 insertions(+), 21 deletions(-) --- a/kernel/module.c +++ b/kernel/module.c @@ -1451,8 +1451,7 @@ static inline bool sect_empty(const Elf_ } struct module_sect_attr { - struct module_attribute mattr; - char *name; + struct bin_attribute battr; unsigned long address; }; @@ -1462,11 +1461,16 @@ struct module_sect_attrs { struct module_sect_attr attrs[0]; }; -static ssize_t module_sect_show(struct module_attribute *mattr, - struct module_kobject *mk, char *buf) +static ssize_t module_sect_read(struct file *file, struct kobject *kobj, + struct bin_attribute *battr, + char *buf, loff_t pos, size_t count) { struct module_sect_attr *sattr = - container_of(mattr, struct module_sect_attr, mattr); + container_of(battr, struct module_sect_attr, battr); + + if (pos != 0) + return -EINVAL; + return sprintf(buf, "0x%px\n", kptr_restrict < 2 ? (void *)sattr->address : NULL); } @@ -1476,7 +1480,7 @@ static void free_sect_attrs(struct modul unsigned int section; for (section = 0; section < sect_attrs->nsections; section++) - kfree(sect_attrs->attrs[section].name); + kfree(sect_attrs->attrs[section].battr.attr.name); kfree(sect_attrs); } @@ -1485,42 +1489,41 @@ static void add_sect_attrs(struct module unsigned int nloaded = 0, i, size[2]; struct module_sect_attrs *sect_attrs; struct module_sect_attr *sattr; - struct attribute **gattr; + struct bin_attribute **gattr; /* Count loaded sections and allocate structures */ for (i = 0; i < info->hdr->e_shnum; i++) if (!sect_empty(&info->sechdrs[i])) nloaded++; size[0] = ALIGN(struct_size(sect_attrs, attrs, nloaded), - sizeof(sect_attrs->grp.attrs[0])); - size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]); + sizeof(sect_attrs->grp.bin_attrs[0])); + size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.bin_attrs[0]); sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL); if (sect_attrs == NULL) return; /* Setup section attributes. */ sect_attrs->grp.name = "sections"; - sect_attrs->grp.attrs = (void *)sect_attrs + size[0]; + sect_attrs->grp.bin_attrs = (void *)sect_attrs + size[0]; sect_attrs->nsections = 0; sattr = §_attrs->attrs[0]; - gattr = §_attrs->grp.attrs[0]; + gattr = §_attrs->grp.bin_attrs[0]; for (i = 0; i < info->hdr->e_shnum; i++) { Elf_Shdr *sec = &info->sechdrs[i]; if (sect_empty(sec)) continue; + sysfs_bin_attr_init(&sattr->battr); sattr->address = sec->sh_addr; - sattr->name = kstrdup(info->secstrings + sec->sh_name, - GFP_KERNEL); - if (sattr->name == NULL) + sattr->battr.attr.name = + kstrdup(info->secstrings + sec->sh_name, GFP_KERNEL); + if (sattr->battr.attr.name == NULL) goto out; sect_attrs->nsections++; - sysfs_attr_init(&sattr->mattr.attr); - sattr->mattr.show = module_sect_show; - sattr->mattr.store = NULL; - sattr->mattr.attr.name = sattr->name; - sattr->mattr.attr.mode = S_IRUSR; - *(gattr++) = &(sattr++)->mattr.attr; + sattr->battr.read = module_sect_read; + sattr->battr.size = 3 /* "0x", "\n" */ + (BITS_PER_LONG / 4); + sattr->battr.attr.mode = 0400; + *(gattr++) = &(sattr++)->battr; } *gattr = NULL; @@ -1610,7 +1613,7 @@ static void add_notes_attrs(struct modul continue; if (info->sechdrs[i].sh_type == SHT_NOTE) { sysfs_bin_attr_init(nattr); - nattr->attr.name = mod->sect_attrs->attrs[loaded].name; + nattr->attr.name = mod->sect_attrs->attrs[loaded].battr.attr.name; nattr->attr.mode = S_IRUGO; nattr->size = info->sechdrs[i].sh_size; nattr->private = (void *) info->sechdrs[i].sh_addr;