From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b="AO22bOAm" Received: from mx0b-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4037E197; Tue, 21 Nov 2023 17:18:42 -0800 (PST) Received: from pps.filterd (m0353724.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 3AM0GARr010991; Wed, 22 Nov 2023 01:18:19 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=message-id : subject : from : to : cc : date : in-reply-to : references : content-type : mime-version : content-transfer-encoding; s=pp1; bh=fnovNk6AHp/U+kSPAbJeVqRSf5N2j37dZWSMh8VhmEs=; b=AO22bOAmcpDFQBiARFxQ9s7TSfDOSrHL8qa5e1FIcyR6jytGUg8tfBausyPhSoA4g165 Qp1WFKkCNJAhJNcpp44te9bfNaSm5JnNPmflfTiLEUijsgAP325wx5/hYk9Wxambm/4n 0mLY1t5FdZ4qomLAeq6KbU5HMu+2A5KJYnJiFwYAmusya7PhQzhHXZtxD9KyseEPp+El 5HA/5wzEWxbM+xHvf5PhYfhf3YKy3rZ+JcZ4jRhNo+83cyhIj+jUyqiHB6DhGC5dehxA 6eC9yYUx/MxLUzAuPfES2ReK3D6pIKU+fcHsbgp4PjnawoJDWoD1/MNCMzHmF1trIjhh 3w== Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3uh6xy970d-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 22 Nov 2023 01:18:19 +0000 Received: from m0353724.ppops.net (m0353724.ppops.net [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 3AM1B7Ku003858; Wed, 22 Nov 2023 01:18:18 GMT Received: from ppma22.wdc07v.mail.ibm.com (5c.69.3da9.ip4.static.sl-reverse.com [169.61.105.92]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3uh6xy9702-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 22 Nov 2023 01:18:18 +0000 Received: from pps.filterd (ppma22.wdc07v.mail.ibm.com [127.0.0.1]) by ppma22.wdc07v.mail.ibm.com (8.17.1.19/8.17.1.19) with ESMTP id 3AM1DMYB022360; Wed, 22 Nov 2023 01:18:17 GMT Received: from smtprelay02.dal12v.mail.ibm.com ([172.16.1.4]) by ppma22.wdc07v.mail.ibm.com (PPS) with ESMTPS id 3uf7yymt98-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 22 Nov 2023 01:18:17 +0000 Received: from smtpav06.wdc07v.mail.ibm.com (smtpav06.wdc07v.mail.ibm.com [10.39.53.233]) by smtprelay02.dal12v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 3AM1IG7N33161728 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 22 Nov 2023 01:18:17 GMT Received: from smtpav06.wdc07v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id B8FFB58054; Wed, 22 Nov 2023 01:18:16 +0000 (GMT) Received: from smtpav06.wdc07v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id DA9AF5803F; Wed, 22 Nov 2023 01:18:14 +0000 (GMT) Received: from li-f45666cc-3089-11b2-a85c-c57d1a57929f.ibm.com (unknown [9.61.87.103]) by smtpav06.wdc07v.mail.ibm.com (Postfix) with ESMTP; Wed, 22 Nov 2023 01:18:14 +0000 (GMT) Message-ID: <09adb80a9317062a7139527eb0cbd45bb7d78b4f.camel@linux.ibm.com> Subject: Re: [RFC V2] IMA Log Snapshotting Design Proposal From: Mimi Zohar To: Tushar Sugandhi , Paul Moore Cc: linux-integrity@vger.kernel.org, peterhuewe@gmx.de, Jarkko Sakkinen , jgg@ziepe.ca, Ken Goldman , bhe@redhat.com, vgoyal@redhat.com, Dave Young , "kexec@lists.infradead.org" , jmorris@namei.org, serge@hallyn.com, James Bottomley , linux-security-module@vger.kernel.org, Tyler Hicks , Lakshmi Ramasubramanian , Sush Shringarputale Date: Tue, 21 Nov 2023 20:18:14 -0500 In-Reply-To: References: <6c0c32d5-e636-2a0e-5bdf-538c904ceea3@linux.microsoft.com> <8bff2bf1a4629aacec7b6311d77f233cb75b2f8a.camel@linux.ibm.com> Content-Type: text/plain; charset="ISO-8859-15" X-Mailer: Evolution 3.28.5 (3.28.5-22.el8) Precedence: bulk X-Mailing-List: linux-security-module@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: cINbTcskzZy0QxIrZQAVWvcTkZpauqXr X-Proofpoint-GUID: wIOEghWbEitrioMbjd5cWPJ6cHOPa2P_ X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.987,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-11-21_16,2023-11-21_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 impostorscore=0 mlxscore=0 mlxlogscore=999 suspectscore=0 lowpriorityscore=0 phishscore=0 adultscore=0 spamscore=0 bulkscore=0 malwarescore=0 priorityscore=1501 clxscore=1011 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2311060000 definitions=main-2311220006 On Tue, 2023-11-21 at 17:01 -0800, Tushar Sugandhi wrote: > Hi Mimi, > To address your concern about pausing the measurements - > We are not proposing to pause the measurements for the entire duration > of UM <--> Kernel interaction while taking a snapshot. > > We are simply proposing to pause the measurements when we get the TPM > PCR quotes to add them to "snapshot_aggregate". (which should be a very > small time window). IMA already has this mechanism when two separate > modules try to add entry to IMA log - by using > mutex_lock(&ima_extend_list_mutex); in ima_add_template_entry. > > > We plan to use this existing locking functionality. > Hope this addresses your concern about pausing extending the measurement > list. Each TPM PCR read is a separate TPM command. Have you done any performance anlaysis to see how long it actually takes to calculate the "snapshot_aggregate" with a physical TPM? The "snapshot_aggregate" is a new critical-data and should be upstreamed independently of this patch set. -- thanks, Mimi