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=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 A744EC76188 for ; Fri, 19 Jul 2019 12:28:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8A8A820873 for ; Fri, 19 Jul 2019 12:28:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728388AbfGSM2q (ORCPT ); Fri, 19 Jul 2019 08:28:46 -0400 Received: from mx2.suse.de ([195.135.220.15]:49126 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727637AbfGSM2o (ORCPT ); Fri, 19 Jul 2019 08:28:44 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id DFDCAAECD; Fri, 19 Jul 2019 12:28:42 +0000 (UTC) From: Miroslav Benes To: jikos@kernel.org, jpoimboe@redhat.com, pmladek@suse.com Cc: joe.lawrence@redhat.com, live-patching@vger.kernel.org, linux-kernel@vger.kernel.org, Miroslav Benes Subject: [PATCH 1/2] livepatch: Nullify obj->mod in klp_module_coming()'s error path Date: Fri, 19 Jul 2019 14:28:39 +0200 Message-Id: <20190719122840.15353-2-mbenes@suse.cz> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190719122840.15353-1-mbenes@suse.cz> References: <20190719122840.15353-1-mbenes@suse.cz> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org klp_module_coming() is called for every module appearing in the system. It sets obj->mod to a patched module for klp_object obj. Unfortunately it leaves it set even if an error happens later in the function and the patched module is not allowed to be loaded. klp_is_object_loaded() uses obj->mod variable and could currently give a wrong return value. The bug is probably harmless as of now. Signed-off-by: Miroslav Benes Reviewed-by: Petr Mladek --- kernel/livepatch/core.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index c4ce08f43bd6..ab4a4606d19b 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -1175,6 +1175,7 @@ int klp_module_coming(struct module *mod) pr_warn("patch '%s' failed for module '%s', refusing to load module '%s'\n", patch->mod->name, obj->mod->name, obj->mod->name); mod->klp_alive = false; + obj->mod = NULL; klp_cleanup_module_patches_limited(mod, patch); mutex_unlock(&klp_mutex); -- 2.22.0