From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 721A51A9B3E for ; Tue, 8 Apr 2025 02:24:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744079052; cv=none; b=EeF6wVRnERM7E/ZadbbC4awA3UkPad3HWOHsC2VZ1QWY66gWvZNm0/eVp02YQOy25So4/Be38HKRV1TNidwlapk60Zy1I5SFJKc6hsV4NLe0LotTL+c9dFBckDScFsi6obLksxRzrbm3kbJI2XYiEnNyhfkOOzEXe7U06YsSMmM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744079052; c=relaxed/simple; bh=MdkpQCnMo49opJex7OZUG+NIbeQFZNJQY/fbJ6jtgho=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ZgCsII9RBqpR9dI3Z/WOKD/CT9LYIwjOImCCZTpsbkXU8ZW4JF6S2jE6prFt/SldXy95duUXvb8C7ZdDPEtBgsX3MY4PhS22j+VqTRMkJnTR1+0d3eq/xXFyaI9loQOM0B4Pt9YFZIFnumiKCfO8rwS2OEzelh2iP0SfZMq9l6o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=OD1W9KMo; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="OD1W9KMo" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1744079048; 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=K7shp0i8xV6W4sEMIfoyEtGIoaU0RHBOh45LNxxy8wY=; b=OD1W9KMoJbw9AcFui1abBTsTYzqPwPRubYygmae/7BLQsWikmQq/Lva1fG5YRuKNYwanfm CNuRe0C4wfaFP1+DPAdzN3NbyCy/UJpkOO37UHo3cFxsEe+X0ulJKV0yMl40HKyyejahLe QfgltisL8kztjW30SixWTeEiGAFMxSM= 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-475-fVNTxx_CPL6CJ9AhxUkyVA-1; Mon, 07 Apr 2025 22:24:04 -0400 X-MC-Unique: fVNTxx_CPL6CJ9AhxUkyVA-1 X-Mimecast-MFC-AGG-ID: fVNTxx_CPL6CJ9AhxUkyVA_1744079042 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (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 0CEC01956048; Tue, 8 Apr 2025 02:24:01 +0000 (UTC) Received: from localhost (unknown [10.72.112.61]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 71DE6180B48C; Tue, 8 Apr 2025 02:23:58 +0000 (UTC) Date: Tue, 8 Apr 2025 10:23:53 +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 v11 1/9] ima: rename variable the set_file "file" to "ima_kexec_file" Message-ID: References: <20250402124725.5601-1-chenste@linux.microsoft.com> <20250402124725.5601-2-chenste@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-security-module@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250402124725.5601-2-chenste@linux.microsoft.com> X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 On 04/02/25 at 05:47am, steven chen wrote: > The current kernel behavior is IMA measurements snapshot is taken at > kexec 'load' and not at kexec 'execute'. IMA log is then carried > over to the new kernel after kexec 'execute'. However, the time gap > between kexec load and kexec reboot can be very long. During this > time window, new events extended into TPM PCRs miss the chance > to be carried over to the second kernel. > > To address the above, the following approach is proposed: > - Allocate the necessary buffer during the kexec load phase. > - Populate this buffer with the IMA measurements during > the kexec execute phase. > > In the current implementation, a local variable "file" of type seq_file > is used in the API ima_dump_measurement_list() to store the IMA measurements > to be carried over across kexec system call. To make this buffer accessible > at kexec 'execute' time, rename it to "ima_kexec_file" before making it > a file variable to better reflect its purpose. > > Renaming the local variable "file" of type seq_file defined in the > ima_dump_measurement_list function to "ima_kexec_file" will improve code > readability and maintainability by making the variable's role more explicit. Seems it's clearer with below paragraph to replace the whole log: ===== Rename the local variable "file" of type seq_file defined in the ima_dump_measurement_list function to "ima_kexec_file" to improve code readability and maintainability by making the variable's role more explicit. ===== The code change looks good to me. > > Suggested-by: Mimi Zohar > Signed-off-by: steven chen > Reviewed-by: Stefan Berger If there's code change in patch content, the reviewing tag should be reset so that reviewing is taken again on the new change. > --- > security/integrity/ima/ima_kexec.c | 31 +++++++++++++++--------------- > 1 file changed, 16 insertions(+), 15 deletions(-) > > diff --git a/security/integrity/ima/ima_kexec.c b/security/integrity/ima/ima_kexec.c > index 9d45f4d26f73..650beb74346c 100644 > --- a/security/integrity/ima/ima_kexec.c > +++ b/security/integrity/ima/ima_kexec.c > @@ -18,30 +18,30 @@ > static int ima_dump_measurement_list(unsigned long *buffer_size, void **buffer, > unsigned long segment_size) > { > + struct seq_file ima_kexec_file; > struct ima_queue_entry *qe; > - struct seq_file file; > struct ima_kexec_hdr khdr; > int ret = 0; > > /* segment size can't change between kexec load and execute */ > - file.buf = vmalloc(segment_size); > - if (!file.buf) { > + ima_kexec_file.buf = vmalloc(segment_size); > + if (!ima_kexec_file.buf) { > ret = -ENOMEM; > goto out; > } > > - file.file = NULL; > - file.size = segment_size; > - file.read_pos = 0; > - file.count = sizeof(khdr); /* reserved space */ > + ima_kexec_file.file = NULL; > + ima_kexec_file.size = segment_size; > + ima_kexec_file.read_pos = 0; > + ima_kexec_file.count = sizeof(khdr); /* reserved space */ > > memset(&khdr, 0, sizeof(khdr)); > khdr.version = 1; > /* This is an append-only list, no need to hold the RCU read lock */ > list_for_each_entry_rcu(qe, &ima_measurements, later, true) { > - if (file.count < file.size) { > + if (ima_kexec_file.count < ima_kexec_file.size) { > khdr.count++; > - ima_measurements_show(&file, qe); > + ima_measurements_show(&ima_kexec_file, qe); > } else { > ret = -EINVAL; > break; > @@ -55,23 +55,24 @@ static int ima_dump_measurement_list(unsigned long *buffer_size, void **buffer, > * fill in reserved space with some buffer details > * (eg. version, buffer size, number of measurements) > */ > - khdr.buffer_size = file.count; > + khdr.buffer_size = ima_kexec_file.count; > if (ima_canonical_fmt) { > khdr.version = cpu_to_le16(khdr.version); > khdr.count = cpu_to_le64(khdr.count); > khdr.buffer_size = cpu_to_le64(khdr.buffer_size); > } > - memcpy(file.buf, &khdr, sizeof(khdr)); > + memcpy(ima_kexec_file.buf, &khdr, sizeof(khdr)); > > print_hex_dump_debug("ima dump: ", DUMP_PREFIX_NONE, 16, 1, > - file.buf, file.count < 100 ? file.count : 100, > + ima_kexec_file.buf, ima_kexec_file.count < 100 ? > + ima_kexec_file.count : 100, > true); > > - *buffer_size = file.count; > - *buffer = file.buf; > + *buffer_size = ima_kexec_file.count; > + *buffer = ima_kexec_file.buf; > out: > if (ret == -EINVAL) > - vfree(file.buf); > + vfree(ima_kexec_file.buf); > return ret; > } > > -- > 2.25.1 >