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=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 7F4F8C11F69 for ; Tue, 13 Jul 2021 05:31:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5F368601FE for ; Tue, 13 Jul 2021 05:31:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230374AbhGMFed (ORCPT ); Tue, 13 Jul 2021 01:34:33 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:63084 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S231998AbhGMFe2 (ORCPT ); Tue, 13 Jul 2021 01:34:28 -0400 Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.43/8.16.0.43) with SMTP id 16D541WM107407; Tue, 13 Jul 2021 01:31:23 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding; s=pp1; bh=Kwi7foOKwhU8NgG5vG7fgNdpivTmYOH87NzNnOWfJT4=; b=Le9FIaAPo8eDCNq8REyGHhF3xmUll/1dd2wHc0ckZenz22KDc0PLyjztRYzc75/3E54p lV66uWpmh4hE3aOmcjZE3Au/QBIQLKhr6FF+TnyKmC3cVLOjG5k5wo7/r/j1R/tZO5Wz 1SjqGrXm50OKcNC1ATnP5m1aV66ay2FhroaT0W7UXEo4ddI97sP9i6NiOsSyt+lkQefA op4pOVrVJt3Vu4XKyn2bYT/PItdQQgfeg4WVflItjmMycnIIPbO9X+7zs7uMAv5upXoZ +SZxAxVQj4NZJ/WqTWpNOZjWbALJQQIvFD6ogWC3i9BudCnLFrjenc5xc3/OLEYw845O 9A== Received: from pps.reinject (localhost [127.0.0.1]) by mx0b-001b2d01.pphosted.com with ESMTP id 39qs117ra4-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 13 Jul 2021 01:31:22 -0400 Received: from m0098419.ppops.net (m0098419.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.43/8.16.0.43) with SMTP id 16D54Jio108705; Tue, 13 Jul 2021 01:31:22 -0400 Received: from ppma01wdc.us.ibm.com (fd.55.37a9.ip4.static.sl-reverse.com [169.55.85.253]) by mx0b-001b2d01.pphosted.com with ESMTP id 39qs117r9s-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 13 Jul 2021 01:31:22 -0400 Received: from pps.filterd (ppma01wdc.us.ibm.com [127.0.0.1]) by ppma01wdc.us.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 16D5RUY2010788; Tue, 13 Jul 2021 05:31:21 GMT Received: from b03cxnp08026.gho.boulder.ibm.com (b03cxnp08026.gho.boulder.ibm.com [9.17.130.18]) by ppma01wdc.us.ibm.com with ESMTP id 39q36ayrf5-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 13 Jul 2021 05:31:21 +0000 Received: from b03ledav005.gho.boulder.ibm.com (b03ledav005.gho.boulder.ibm.com [9.17.130.236]) by b03cxnp08026.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 16D5VKhp28246524 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 13 Jul 2021 05:31:20 GMT Received: from b03ledav005.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 488D9BE04F; Tue, 13 Jul 2021 05:31:20 +0000 (GMT) Received: from b03ledav005.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id F1B46BE053; Tue, 13 Jul 2021 05:31:19 +0000 (GMT) Received: from oc8246131445.ibm.com (unknown [9.163.19.100]) by b03ledav005.gho.boulder.ibm.com (Postfix) with SMTP; Tue, 13 Jul 2021 05:31:19 +0000 (GMT) Received: from oc8246131445.ibm.com (localhost.localdomain [127.0.0.1]) by oc8246131445.ibm.com (Postfix) with ESMTP id 4A441BC0C34; Tue, 13 Jul 2021 00:31:15 -0500 (CDT) From: "Christopher M. Riedl" To: linuxppc-dev@lists.ozlabs.org Cc: tglx@linutronix.de, x86@kernel.org, linux-hardening@vger.kernel.org, keescook@chromium.org, npiggin@gmail.com, dja@axtens.net, peterz@infradead.org Subject: [PATCH v5 8/8] lkdtm/powerpc: Fix code patching hijack test Date: Tue, 13 Jul 2021 00:31:13 -0500 Message-Id: <20210713053113.4632-9-cmr@linux.ibm.com> X-Mailer: git-send-email 2.26.1 In-Reply-To: <20210713053113.4632-1-cmr@linux.ibm.com> References: <20210713053113.4632-1-cmr@linux.ibm.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-TM-AS-GCONF: 00 X-Proofpoint-GUID: cHCthgBcM9xp9Mt9bos8xwQ5FL3n-jCp X-Proofpoint-ORIG-GUID: HDbwSKEE2EoyOQh_byeJIz2jcHRRf7Jr X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.391,18.0.790 definitions=2021-07-13_03:2021-07-13,2021-07-12 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 phishscore=0 adultscore=0 suspectscore=0 impostorscore=0 clxscore=1015 lowpriorityscore=0 bulkscore=0 malwarescore=0 priorityscore=1501 mlxlogscore=999 mlxscore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2104190000 definitions=main-2107130022 Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org Code patching on powerpc with a STRICT_KERNEL_RWX uses a userspace address in a temporary mm on Radix now. Use __put_user() to avoid write failures due to KUAP when attempting a "hijack" on the patching address. __put_user() also works with the non-userspace, vmalloc-based patching address on non-Radix MMUs. Signed-off-by: Christopher M. Riedl --- drivers/misc/lkdtm/perms.c | 9 --------- 1 file changed, 9 deletions(-) diff --git a/drivers/misc/lkdtm/perms.c b/drivers/misc/lkdtm/perms.c index 41e87e5f9cc86..da6a34a0a49fb 100644 --- a/drivers/misc/lkdtm/perms.c +++ b/drivers/misc/lkdtm/perms.c @@ -262,16 +262,7 @@ static inline u32 lkdtm_read_patch_site(void) /* Returns True if the write succeeds */ static inline bool lkdtm_try_write(u32 data, u32 *addr) { -#ifdef CONFIG_PPC - __put_kernel_nofault(addr, &data, u32, err); - return true; - -err: - return false; -#endif -#ifdef CONFIG_X86_64 return !__put_user(data, addr); -#endif } =20 static int lkdtm_patching_cpu(void *data) --=20 2.26.1