From patchwork Fri May 1 14:16:52 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nayna Jain X-Patchwork-Id: 11522607 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9FF89912 for ; Fri, 1 May 2020 14:17:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 920AC20757 for ; Fri, 1 May 2020 14:17:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728886AbgEAORP (ORCPT ); Fri, 1 May 2020 10:17:15 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:36650 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728840AbgEAORO (ORCPT ); Fri, 1 May 2020 10:17:14 -0400 Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 041EDOVo167060; Fri, 1 May 2020 10:17:02 -0400 Received: from ppma03ams.nl.ibm.com (62.31.33a9.ip4.static.sl-reverse.com [169.51.49.98]) by mx0b-001b2d01.pphosted.com with ESMTP id 30r825ts9b-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 01 May 2020 10:17:01 -0400 Received: from pps.filterd (ppma03ams.nl.ibm.com [127.0.0.1]) by ppma03ams.nl.ibm.com (8.16.0.27/8.16.0.27) with SMTP id 041EG4uh013887; Fri, 1 May 2020 14:17:00 GMT Received: from b06cxnps4074.portsmouth.uk.ibm.com (d06relay11.portsmouth.uk.ibm.com [9.149.109.196]) by ppma03ams.nl.ibm.com with ESMTP id 30mcu5vu75-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 01 May 2020 14:17:00 +0000 Received: from d06av26.portsmouth.uk.ibm.com (d06av26.portsmouth.uk.ibm.com [9.149.105.62]) by b06cxnps4074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 041EGvQp57016532 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 1 May 2020 14:16:57 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 50247AE045; Fri, 1 May 2020 14:16:57 +0000 (GMT) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id CA5C9AE053; Fri, 1 May 2020 14:16:55 +0000 (GMT) Received: from swastik.ibm.com (unknown [9.65.217.16]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTP; Fri, 1 May 2020 14:16:55 +0000 (GMT) From: Nayna Jain To: linux-integrity@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Cc: linux-kernel@vger.kernel.org, Mimi Zohar , Michael Ellerman , Nayna Jain Subject: [PATCH v2] powerpc/ima: fix secure boot rules in ima arch policy Date: Fri, 1 May 2020 10:16:52 -0400 Message-Id: <1588342612-14532-1-git-send-email-nayna@linux.ibm.com> X-Mailer: git-send-email 1.8.3.1 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.676 definitions=2020-05-01_07:2020-04-30,2020-05-01 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxlogscore=999 spamscore=0 impostorscore=0 clxscore=1015 phishscore=0 lowpriorityscore=0 priorityscore=1501 malwarescore=0 suspectscore=0 bulkscore=0 mlxscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2005010107 Sender: linux-integrity-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org To prevent verifying the kernel module appended signature twice (finit_module), once by the module_sig_check() and again by IMA, powerpc secure boot rules define an IMA architecture specific policy rule only if CONFIG_MODULE_SIG_FORCE is not enabled. This, unfortunately, does not take into account the ability of enabling "sig_enforce" on the boot command line (module.sig_enforce=1). Including the IMA module appraise rule results in failing the finit_module syscall, unless the module signing public key is loaded onto the IMA keyring. This patch fixes secure boot policy rules to be based on CONFIG_MODULE_SIG instead. Fixes: 4238fad366a6 ("powerpc/ima: Add support to initialize ima policy rules") Signed-off-by: Nayna Jain Signed-off-by: Mimi Zohar --- v2: * Fixes the patch description to specify the problem more clearly as asked by Michael Ellerman. arch/powerpc/kernel/ima_arch.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/kernel/ima_arch.c b/arch/powerpc/kernel/ima_arch.c index e34116255ced..957abd592075 100644 --- a/arch/powerpc/kernel/ima_arch.c +++ b/arch/powerpc/kernel/ima_arch.c @@ -19,12 +19,12 @@ bool arch_ima_get_secureboot(void) * to be stored as an xattr or as an appended signature. * * To avoid duplicate signature verification as much as possible, the IMA - * policy rule for module appraisal is added only if CONFIG_MODULE_SIG_FORCE + * policy rule for module appraisal is added only if CONFIG_MODULE_SIG * is not enabled. */ static const char *const secure_rules[] = { "appraise func=KEXEC_KERNEL_CHECK appraise_flag=check_blacklist appraise_type=imasig|modsig", -#ifndef CONFIG_MODULE_SIG_FORCE +#ifndef CONFIG_MODULE_SIG "appraise func=MODULE_CHECK appraise_flag=check_blacklist appraise_type=imasig|modsig", #endif NULL @@ -50,7 +50,7 @@ static const char *const secure_and_trusted_rules[] = { "measure func=KEXEC_KERNEL_CHECK template=ima-modsig", "measure func=MODULE_CHECK template=ima-modsig", "appraise func=KEXEC_KERNEL_CHECK appraise_flag=check_blacklist appraise_type=imasig|modsig", -#ifndef CONFIG_MODULE_SIG_FORCE +#ifndef CONFIG_MODULE_SIG "appraise func=MODULE_CHECK appraise_flag=check_blacklist appraise_type=imasig|modsig", #endif NULL