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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_2 autolearn=unavailable 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 11A92C2D0D2 for ; Tue, 24 Dec 2019 20:35:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E324A2075E for ; Tue, 24 Dec 2019 20:35:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726203AbfLXUf0 (ORCPT ); Tue, 24 Dec 2019 15:35:26 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:9552 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726214AbfLXUf0 (ORCPT ); Tue, 24 Dec 2019 15:35:26 -0500 Received: from pps.filterd (m0098421.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id xBOKR32J048959 for ; Tue, 24 Dec 2019 15:35:24 -0500 Received: from e06smtp04.uk.ibm.com (e06smtp04.uk.ibm.com [195.75.94.100]) by mx0a-001b2d01.pphosted.com with ESMTP id 2x21wcrrc8-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Tue, 24 Dec 2019 15:35:24 -0500 Received: from localhost by e06smtp04.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Tue, 24 Dec 2019 20:35:17 -0000 Received: from d06av25.portsmouth.uk.ibm.com (d06av25.portsmouth.uk.ibm.com [9.149.105.61]) by b06cxnps4076.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id xBOKZGoE32571470 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 24 Dec 2019 20:35:17 GMT Received: from d06av25.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id D684D11C04A; Tue, 24 Dec 2019 20:35:16 +0000 (GMT) Received: from d06av25.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 93B5F11C04C; Tue, 24 Dec 2019 20:35:15 +0000 (GMT) Received: from localhost.localdomain (unknown [9.80.204.221]) by d06av25.portsmouth.uk.ibm.com (Postfix) with ESMTP; Tue, 24 Dec 2019 20:35:15 +0000 (GMT) Subject: Re: [PATCH v2] IMA: Defined timer to free queued keys From: Mimi Zohar To: Lakshmi Ramasubramanian , James.Bottomley@HansenPartnership.com, linux-integrity@vger.kernel.org Cc: eric.snowberg@oracle.com, dhowells@redhat.com, mathew.j.martineau@linux.intel.com, matthewgarrett@google.com, sashal@kernel.org, jamorris@linux.microsoft.com, linux-kernel@vger.kernel.org, keyrings@vger.kernel.org In-Reply-To: <20191224180114.2772-1-nramas@linux.microsoft.com> References: <20191224180114.2772-1-nramas@linux.microsoft.com> Content-Type: text/plain; charset="UTF-8" Date: Tue, 24 Dec 2019 15:35:04 -0500 Mime-Version: 1.0 X-Mailer: Evolution 3.20.5 (3.20.5-1.fc24) Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 x-cbid: 19122420-0016-0000-0000-000002D7E582 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19122420-0017-0000-0000-0000333A3BA6 Message-Id: <1577219704.4487.2.camel@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.95,18.0.572 definitions=2019-12-24_06:2019-12-24,2019-12-24 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 phishscore=0 spamscore=0 clxscore=1015 malwarescore=0 mlxlogscore=999 impostorscore=0 adultscore=0 mlxscore=0 suspectscore=2 priorityscore=1501 bulkscore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1910280000 definitions=main-1912240180 Sender: linux-integrity-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org On Tue, 2019-12-24 at 10:01 -0800, Lakshmi Ramasubramanian wrote: > keys queued for measurement should be freed if a custom IMA policy > was not loaded. Otherwise, the keys will remain queued forever > consuming kernel memory. > > This patch defines a timer to handle the above scenario. The timer > is setup to expire 5 minutes after IMA initialization is completed. > > If a custom IMA policy is loaded before the timer expires, the timer > is removed and any queued keys are processed for measurement. > But if a custom policy was not loaded, on timer expiration > queued keys are just freed. > > Signed-off-by: Lakshmi Ramasubramanian Thanks.  This patch is now queued in next-integrity-testing. Mimi > --- > security/integrity/ima/ima.h | 2 + > security/integrity/ima/ima_asymmetric_keys.c | 42 ++++++++++++++++++-- > security/integrity/ima/ima_init.c | 8 +++- > 3 files changed, 48 insertions(+), 4 deletions(-) > > diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h > index 97f8a4078483..c483215a9ee5 100644 > --- a/security/integrity/ima/ima.h > +++ b/security/integrity/ima/ima.h > @@ -216,8 +216,10 @@ struct ima_key_entry { > char *keyring_name; > }; > void ima_process_queued_keys(void); > +void ima_init_key_queue(void); > #else > static inline void ima_process_queued_keys(void) {} > +static inline void ima_init_key_queue(void) {} > #endif /* CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE */ > > /* LIM API function definitions */ > diff --git a/security/integrity/ima/ima_asymmetric_keys.c b/security/integrity/ima/ima_asymmetric_keys.c > index 4124f10ff0c2..9ea2233c911a 100644 > --- a/security/integrity/ima/ima_asymmetric_keys.c > +++ b/security/integrity/ima/ima_asymmetric_keys.c > @@ -11,6 +11,7 @@ > > #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt > > +#include > #include > #include "ima.h" > > @@ -26,6 +27,36 @@ static bool ima_process_keys; > static DEFINE_MUTEX(ima_keys_mutex); > static LIST_HEAD(ima_keys); > > +/* > + * If custom IMA policy is not loaded then keys queued up > + * for measurement should be freed. This timer is used > + * for handling this scenario. > + */ > +static long ima_key_queue_timeout = 300000; /* 5 Minutes */ > +static struct timer_list ima_key_queue_timer; > +static bool timer_expired; > + > +/* > + * This timer callback function frees keys that may still be > + * queued up in case custom IMA policy was not loaded. > + */ > +static void ima_timer_handler(struct timer_list *timer) > +{ > + timer_expired = true; > + ima_process_queued_keys(); > +} > + > +/* > + * This function sets up a timer to free queued keys in case > + * custom IMA policy was never loaded. > + */ > +void ima_init_key_queue(void) > +{ > + timer_setup(&ima_key_queue_timer, ima_timer_handler, 0); > + mod_timer(&ima_key_queue_timer, > + jiffies + msecs_to_jiffies(ima_key_queue_timeout)); > +} > + > static void ima_free_key_entry(struct ima_key_entry *entry) > { > if (entry) { > @@ -120,10 +151,15 @@ void ima_process_queued_keys(void) > if (!process) > return; > > + del_timer(&ima_key_queue_timer); > + > list_for_each_entry_safe(entry, tmp, &ima_keys, list) { > - process_buffer_measurement(entry->payload, entry->payload_len, > - entry->keyring_name, KEY_CHECK, 0, > - entry->keyring_name); > + if (!timer_expired) > + process_buffer_measurement(entry->payload, > + entry->payload_len, > + entry->keyring_name, > + KEY_CHECK, 0, > + entry->keyring_name); > list_del(&entry->list); > ima_free_key_entry(entry); > } > diff --git a/security/integrity/ima/ima_init.c b/security/integrity/ima/ima_init.c > index 5d55ade5f3b9..195cb4079b2b 100644 > --- a/security/integrity/ima/ima_init.c > +++ b/security/integrity/ima/ima_init.c > @@ -131,5 +131,11 @@ int __init ima_init(void) > > ima_init_policy(); > > - return ima_fs_init(); > + rc = ima_fs_init(); > + if (rc != 0) > + return rc; > + > + ima_init_key_queue(); > + > + return rc; > }