From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1033000AbeEXLKy (ORCPT ); Thu, 24 May 2018 07:10:54 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:56788 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1033057AbeEXLKl (ORCPT ); Thu, 24 May 2018 07:10:41 -0400 From: Mimi Zohar To: linux-integrity@vger.kernel.org Cc: Mimi Zohar , linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, David Howells , "Luis R . Rodriguez" , Eric Biederman , kexec@lists.infradead.org, Andres Rodriguez , Greg Kroah-Hartman , Ard Biesheuvel , "Luis R . Rodriguez" , Kees Cook Subject: [PATCH v3 4/7] firmware: add call to LSM hook before firmware sysfs fallback Date: Thu, 24 May 2018 07:09:33 -0400 X-Mailer: git-send-email 2.7.5 In-Reply-To: <1527160176-29269-1-git-send-email-zohar@linux.vnet.ibm.com> References: <1527160176-29269-1-git-send-email-zohar@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 18052411-0008-0000-0000-000004FAA7C4 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18052411-0009-0000-0000-00001E8EAFD3 Message-Id: <1527160176-29269-5-git-send-email-zohar@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-05-24_03:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 impostorscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1709140000 definitions=main-1805240132 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add an LSM hook prior to allowing firmware sysfs fallback loading. Signed-off-by: Mimi Zohar Cc: Luis R. Rodriguez Cc: David Howells Cc: Kees Cook Changelog: - call security_kernel_read_blob() - rename the READING_FIRMWARE_FALLBACK kernel_read_file_id enumeration to READING_FIRMWARE_FALLBACK_SYSFS. --- drivers/base/firmware_loader/fallback.c | 7 +++++++ include/linux/fs.h | 1 + 2 files changed, 8 insertions(+) diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c index 358354148dec..ae102efcc9f0 100644 --- a/drivers/base/firmware_loader/fallback.c +++ b/drivers/base/firmware_loader/fallback.c @@ -651,6 +651,8 @@ static bool fw_force_sysfs_fallback(unsigned int opt_flags) static bool fw_run_sysfs_fallback(unsigned int opt_flags) { + int ret; + if (fw_fallback_config.ignore_sysfs_fallback) { pr_info_once("Ignoring firmware sysfs fallback due to sysctl knob\n"); return false; @@ -659,6 +661,11 @@ static bool fw_run_sysfs_fallback(unsigned int opt_flags) if ((opt_flags & FW_OPT_NOFALLBACK)) return false; + /* Also permit LSMs and IMA to fail firmware sysfs fallback */ + ret = security_kernel_read_data(NULL, READING_FIRMWARE_FALLBACK_SYSFS); + if (ret < 0) + return ret; + return fw_force_sysfs_fallback(opt_flags); } diff --git a/include/linux/fs.h b/include/linux/fs.h index 760d8da1b6c7..6e31d9207435 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2810,6 +2810,7 @@ extern int do_pipe_flags(int *, int); id(UNKNOWN, unknown) \ id(FIRMWARE, firmware) \ id(FIRMWARE_PREALLOC_BUFFER, firmware) \ + id(FIRMWARE_FALLBACK_SYSFS, firmware) \ id(MODULE, kernel-module) \ id(KEXEC_IMAGE, kexec-image) \ id(KEXEC_INITRAMFS, kexec-initramfs) \ -- 2.7.5