From patchwork Thu Apr 12 22:41:50 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mimi Zohar X-Patchwork-Id: 10339305 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id CBC8D600D0 for ; Thu, 12 Apr 2018 22:42:56 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D4FB428468 for ; Thu, 12 Apr 2018 22:42:56 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C9D9A284CE; Thu, 12 Apr 2018 22:42:56 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 66CB828468 for ; Thu, 12 Apr 2018 22:42:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753562AbeDLWmO (ORCPT ); Thu, 12 Apr 2018 18:42:14 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:50502 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753525AbeDLWmL (ORCPT ); Thu, 12 Apr 2018 18:42:11 -0400 Received: from pps.filterd (m0098393.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w3CMekdh130003 for ; Thu, 12 Apr 2018 18:42:11 -0400 Received: from e06smtp12.uk.ibm.com (e06smtp12.uk.ibm.com [195.75.94.108]) by mx0a-001b2d01.pphosted.com with ESMTP id 2hacny96j1-1 (version=TLSv1.2 cipher=AES256-SHA256 bits=256 verify=NOT) for ; Thu, 12 Apr 2018 18:42:10 -0400 Received: from localhost by e06smtp12.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Thu, 12 Apr 2018 23:42:06 +0100 Received: from d06av26.portsmouth.uk.ibm.com (d06av26.portsmouth.uk.ibm.com [9.149.105.62]) by b06cxnps4076.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id w3CMg5o955902378; Thu, 12 Apr 2018 22:42:05 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 8CD5AAE056; Thu, 12 Apr 2018 23:32:00 +0100 (BST) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 7C34DAE045; Thu, 12 Apr 2018 23:31:59 +0100 (BST) Received: from localhost.ibm.com (unknown [9.80.84.218]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTP; Thu, 12 Apr 2018 23:31:59 +0100 (BST) 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: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: X-Virus-Scanned: ClamAV using ClamSMTP 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. */