From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753610AbeDLWmO (ORCPT ); Thu, 12 Apr 2018 18:42:14 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:53900 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753478AbeDLWmL (ORCPT ); Thu, 12 Apr 2018 18:42:11 -0400 From: Mimi Zohar To: David Howells Cc: Matthew Garrett , Mimi Zohar , linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, Eric Biederman , kexec@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH 2/3] kexec: call LSM hook for kexec_load syscall Date: Thu, 12 Apr 2018 18:41:50 -0400 X-Mailer: git-send-email 2.7.5 In-Reply-To: <1523572911-16363-1-git-send-email-zohar@linux.vnet.ibm.com> References: <1523572911-16363-1-git-send-email-zohar@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 18041222-0008-0000-0000-000004E9F1DF X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18041222-0009-0000-0000-00001E7DFCF3 Message-Id: <1523572911-16363-3-git-send-email-zohar@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-04-12_13:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 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-1804120213 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Allow LSMs and IMA to differentiate between the kexec_load and kexec_file_load syscalls by adding an "unnecessary" call to security_kernel_read_file() in kexec_load. This would be similar to the existing init_module syscall calling security_kernel_read_file(). Signed-off-by: Mimi Zohar --- kernel/kexec.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/kernel/kexec.c b/kernel/kexec.c index aed8fb2564b3..d1386cfc6796 100644 --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include #include @@ -195,11 +196,21 @@ static int do_kexec_load(unsigned long entry, unsigned long nr_segments, static inline int kexec_load_check(unsigned long nr_segments, unsigned long flags) { + int result; + /* We only trust the superuser with rebooting the system. */ if (!capable(CAP_SYS_BOOT) || kexec_load_disabled) return -EPERM; /* + * Allow LSMs and IMA to differentiate between kexec_load and + * kexec_file_load syscalls. + */ + result = security_kernel_read_file(NULL, READING_KEXEC_IMAGE); + if (result < 0) + return result; + + /* * Verify we have a legal set of flags * This leaves us room for future extensions. */ -- 2.7.5