Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932180AbcDLGvV (ORCPT ); Tue, 12 Apr 2016 02:51:21 -0400 Received: from mx2.suse.de ([195.135.220.15]:60102 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752756AbcDLGvU (ORCPT ); Tue, 12 Apr 2016 02:51:20 -0400 Date: Tue, 12 Apr 2016 08:50:25 +0200 From: Libor Pechacek To: Rusty Russell Cc: linux-kernel@vger.kernel.org Subject: [PATCH] module: Issue warnings when tainting kernel Message-ID: <20160412064737.GA5549@fm.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1806 Lines: 49 While most of the locations where a kernel taint bit is set are accompanied with a warning message, there are two which set their bits silently. If the tainting module gets unloaded later on, it is almost impossible to tell what was the reason for setting the flag. Signed-off-by: Libor Pechacek --- kernel/module.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/kernel/module.c b/kernel/module.c index 041200ca4a2d..e2d83d77a0e9 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -2812,8 +2812,12 @@ static int check_modinfo(struct module *mod, struct load_info *info, int flags) return -ENOEXEC; } - if (!get_modinfo(info, "intree")) + if (!get_modinfo(info, "intree")) { + if (!test_taint(TAINT_OOT_MODULE)) + pr_warn("%s: loading out-of-tree module taints kernel.\n", + mod->name); add_taint_module(mod, TAINT_OOT_MODULE, LOCKDEP_STILL_OK); + } if (get_modinfo(info, "staging")) { add_taint_module(mod, TAINT_CRAP, LOCKDEP_STILL_OK); @@ -2978,6 +2982,8 @@ static int move_module(struct module *mod, struct load_info *info) static int check_module_license_and_versions(struct module *mod) { + int prev_taint = test_taint(TAINT_PROPRIETARY_MODULE); + /* * ndiswrapper is under GPL by itself, but loads proprietary modules. * Don't use add_taint_module(), as it would prevent ndiswrapper from @@ -2996,6 +3002,9 @@ static int check_module_license_and_versions(struct module *mod) add_taint_module(mod, TAINT_PROPRIETARY_MODULE, LOCKDEP_NOW_UNRELIABLE); + if (!prev_taint && test_taint(TAINT_PROPRIETARY_MODULE)) + pr_warn("%s: module license taints kernel.\n", mod->name); + #ifdef CONFIG_MODVERSIONS if ((mod->num_syms && !mod->crcs) || (mod->num_gpl_syms && !mod->gpl_crcs) -- 1.7.12.4