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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id ACFD8C369AB for ; Fri, 18 Apr 2025 08:41:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=oGpLEGpFPjLHr2TI5L2WF5TxWp0RKlr+m9WjaH1iqOo=; b=nNiLPUl2VcQBLOklkPxBe+tMph pL2dbw6QMDYGMhoPzCCnky5V2dMSWv/kr0IvYcLlKEpvmrwESRu66JWZh4kaZEjaixv5MSOV7crxJ vE1eCWfsfzrdvl91LfuBUNivZUW3w7PsmlNwjiF+0A1PRz1SZqbro/fr1xjIwgGnPeRpSS/jGNQCk PCCjUfVqedtVaQHULBSVEbo67Q1lR3mo//KK2phxmtt9LlRBWyz4fKIV1jG5mJlU+41H6EgO6fv0y WXLD7dl9RtdTOYkMvBAjrX1+mmW1bJW6OVfDwZQvPpJX7Punwb8qveBLionQS++MvMnr8uR31Dig/ G7Sufz3Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1u5hHa-0000000FeJw-16ps; Fri, 18 Apr 2025 08:41:10 +0000 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1u5gsN-0000000Farv-3DJr for kexec@lists.infradead.org; Fri, 18 Apr 2025 08:15:09 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1744964106; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=oGpLEGpFPjLHr2TI5L2WF5TxWp0RKlr+m9WjaH1iqOo=; b=b291f50HF/sBX37qNLkEe8WmzSR7j3XdtIeN11A4C08c2n7g1IgsdX4G20p9mHwPgAY6rR 1lu6SZFuEEl6gGXYS2RWrPQJMxAtldbQ/b/T3W5pFidNwsP4woAf9361/FcUBHcIxF3iTa 7rs1tL9iSV1Z1pVSLxeUm7mU36yne98= Received: from mx-prod-mc-04.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-586-SJ0K13ASMYa3gF71ua8eWQ-1; Fri, 18 Apr 2025 04:15:04 -0400 X-MC-Unique: SJ0K13ASMYa3gF71ua8eWQ-1 X-Mimecast-MFC-AGG-ID: SJ0K13ASMYa3gF71ua8eWQ_1744964102 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 4C8E819560AB; Fri, 18 Apr 2025 08:15:01 +0000 (UTC) Received: from localhost (unknown [10.72.112.33]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id EB5B519560A3; Fri, 18 Apr 2025 08:14:58 +0000 (UTC) Date: Fri, 18 Apr 2025 16:14:54 +0800 From: Baoquan He To: steven chen Cc: zohar@linux.ibm.com, stefanb@linux.ibm.com, roberto.sassu@huaweicloud.com, roberto.sassu@huawei.com, eric.snowberg@oracle.com, ebiederm@xmission.com, paul@paul-moore.com, code@tyhicks.com, bauermann@kolabnow.com, linux-integrity@vger.kernel.org, kexec@lists.infradead.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, madvenka@linux.microsoft.com, nramas@linux.microsoft.com, James.Bottomley@hansenpartnership.com, vgoyal@redhat.com, dyoung@redhat.com Subject: Re: [PATCH v12 8/9] ima: make the kexec extra memory configurable Message-ID: References: <20250416021028.1403-1-chenste@linux.microsoft.com> <20250416021028.1403-9-chenste@linux.microsoft.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250416021028.1403-9-chenste@linux.microsoft.com> X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250418_011507_878537_BAA231E3 X-CRM114-Status: GOOD ( 25.33 ) X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "kexec" Errors-To: kexec-bounces+kexec=archiver.kernel.org@lists.infradead.org On 04/15/25 at 07:10pm, steven chen wrote: > From: Steven Chen > > The extra memory allocated for carrying the IMA measurement list across > kexec is hard-coded as half a PAGE. Make it configurable. > > Define a Kconfig option, IMA_KEXEC_EXTRA_MEMORY_KB, to configure the > extra memory (in kb) to be allocated for IMA measurements added during > kexec soft reboot. Ensure the default value of the option is set such > that extra half a page of memory for additional measurements is allocated > for the additional measurements. > > Update ima_add_kexec_buffer() function to allocate memory based on the > Kconfig option value, rather than the currently hard-coded one. > > Suggested-by: Stefan Berger > Signed-off-by: Tushar Sugandhi ^^^^^^^^^^^^^^^^ > Signed-off-by: Steven Chen > --- > security/integrity/ima/Kconfig | 11 +++++++++++ > security/integrity/ima/ima_kexec.c | 16 +++++++++++----- > 2 files changed, 22 insertions(+), 5 deletions(-) The contributor's tag need be updated too, otherwise, Acked-by: Baoquan He > > diff --git a/security/integrity/ima/Kconfig b/security/integrity/ima/Kconfig > index 475c32615006..976e75f9b9ba 100644 > --- a/security/integrity/ima/Kconfig > +++ b/security/integrity/ima/Kconfig > @@ -321,4 +321,15 @@ config IMA_DISABLE_HTABLE > help > This option disables htable to allow measurement of duplicate records. > > +config IMA_KEXEC_EXTRA_MEMORY_KB > + int "Extra memory for IMA measurements added during kexec soft reboot" > + range 0 40 > + depends on IMA_KEXEC > + default 0 > + help > + IMA_KEXEC_EXTRA_MEMORY_KB determines the extra memory to be > + allocated (in kb) for IMA measurements added during kexec soft reboot. > + If set to the default value of 0, an extra half page of memory for those > + additional measurements will be allocated. > + > endif > diff --git a/security/integrity/ima/ima_kexec.c b/security/integrity/ima/ima_kexec.c > index ed867734ee70..d1c9d369ba08 100644 > --- a/security/integrity/ima/ima_kexec.c > +++ b/security/integrity/ima/ima_kexec.c > @@ -118,6 +118,7 @@ void ima_add_kexec_buffer(struct kimage *image) > .buf_min = 0, .buf_max = ULONG_MAX, > .top_down = true }; > unsigned long binary_runtime_size; > + unsigned long extra_memory; > > /* use more understandable variable names than defined in kbuf */ > size_t kexec_buffer_size = 0; > @@ -125,15 +126,20 @@ void ima_add_kexec_buffer(struct kimage *image) > int ret; > > /* > - * Reserve an extra half page of memory for additional measurements > - * added during the kexec load. > + * Reserve extra memory for measurements added during kexec. > */ > - binary_runtime_size = ima_get_binary_runtime_size(); > + if (CONFIG_IMA_KEXEC_EXTRA_MEMORY_KB <= 0) > + extra_memory = PAGE_SIZE / 2; > + else > + extra_memory = CONFIG_IMA_KEXEC_EXTRA_MEMORY_KB * 1024; > + > + binary_runtime_size = ima_get_binary_runtime_size() + extra_memory; > + > if (binary_runtime_size >= ULONG_MAX - PAGE_SIZE) > kexec_segment_size = ULONG_MAX; > else > - kexec_segment_size = ALIGN(ima_get_binary_runtime_size() + > - PAGE_SIZE / 2, PAGE_SIZE); > + kexec_segment_size = ALIGN(binary_runtime_size, PAGE_SIZE); > + > if ((kexec_segment_size == ULONG_MAX) || > ((kexec_segment_size >> PAGE_SHIFT) > totalram_pages() / 2)) { > pr_err("Binary measurement list too large.\n"); > -- > 2.43.0 >