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 C89CF25F7AA for ; Tue, 8 Apr 2025 02:58:37 +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=1744081123; cv=none; b=V5LjJpBRAq9ECduwaJl8VWKGOpirT/xHCszhom+1BSAb2Ni+gCtO6bB+PYtrnPOFpnzUcWuRLqCZmjT9lefrvtdhbgOIUPUW8B1bwe6f2anB+B10uWmSuFu62+/1UkNP/gnYKVdqfML/q5+cuMQDU7HoTHK0xlvKx3UiRZicYLk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744081123; c=relaxed/simple; bh=7JUffUBNK5M/+Y/oT2ouv6ujQQPH6yKbolK49qymFSs=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=mb6vv9zlEzWgPDzoQGXHSPewzf/sY4U8o+VgVs+YIC0mPpSeIvlxSr6C1d2YFdyfkQ1EcAuf/D/EHGUIjqRR18r/r7v7Zjls4UCWGuPGFeSgC1mw6CBQKHJn4xER7H3rsMiFRhAEYsAFr0rnVxDAy98cu4oSJmkC7O6SY7C1oeA= 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=VeGSOw4f; 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="VeGSOw4f" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1744081116; 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=kaJaXSVbP57MvATcjgNBp7/OlnZPTiwF4HxV8S9Zb0k=; b=VeGSOw4fYH+Bie3vm8tKjUxXMMuk7RH8puzMjIopOmjvld3yWYdZEj0QIDLaJvOD/2Thib IeXmv9GibdHYz8HcHX3l9fkDLCiCBJC+I+7AaVdCEEnQsAL6o1ABzJ+euj0zY8qFTqSNLN /8cH/hb0ZasqhHAxyCWQlPWhcIlez/8= 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-615-mIpEH9ViNumXuntP7aeqvQ-1; Mon, 07 Apr 2025 22:58:32 -0400 X-MC-Unique: mIpEH9ViNumXuntP7aeqvQ-1 X-Mimecast-MFC-AGG-ID: mIpEH9ViNumXuntP7aeqvQ_1744081110 Received: from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111]) (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 869991955DC6; Tue, 8 Apr 2025 02:58:29 +0000 (UTC) Received: from localhost (unknown [10.72.112.61]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 982FB1801752; Tue, 8 Apr 2025 02:58:26 +0000 (UTC) Date: Tue, 8 Apr 2025 10:58:21 +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 2/9] ima: define and call ima_alloc_kexec_file_buf() Message-ID: References: <20250402124725.5601-1-chenste@linux.microsoft.com> <20250402124725.5601-3-chenste@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-kernel@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: <20250402124725.5601-3-chenste@linux.microsoft.com> X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 On 04/02/25 at 05:47am, steven chen wrote: > In the current implementation, the ima_dump_measurement_list() API is > called during the kexec "load" phase, where a buffer is allocated and > the measurement records are copied. Due to this, new events added after > kexec load but before kexec execute are not carried over to the new kernel > during kexec operation > > To allow the buffer allocation and population to be separated into distinct > steps, make the function local seq_file "ima_kexec_file" to a file variable. > > Carrying the IMA measurement list across kexec requires allocating a > buffer and copying the measurement records. Separate allocating the > buffer and copying the measurement records into separate functions in > order to allocate the buffer at kexec 'load' and copy the measurements > at kexec 'execute'. > > Signed-off-by: Tushar Sugandhi > Signed-off-by: steven chen > --- > security/integrity/ima/ima_kexec.c | 46 +++++++++++++++++++++++------- > 1 file changed, 35 insertions(+), 11 deletions(-) LGTM, Acked-by: Baoquan He > > diff --git a/security/integrity/ima/ima_kexec.c b/security/integrity/ima/ima_kexec.c > index 650beb74346c..b12ac3619b8f 100644 > --- a/security/integrity/ima/ima_kexec.c > +++ b/security/integrity/ima/ima_kexec.c > @@ -15,26 +15,46 @@ > #include "ima.h" > > #ifdef CONFIG_IMA_KEXEC > +static struct seq_file ima_kexec_file; > + > +static void ima_free_kexec_file_buf(struct seq_file *sf) > +{ > + vfree(sf->buf); > + sf->buf = NULL; > + sf->size = 0; > + sf->read_pos = 0; > + sf->count = 0; > +} > + > +static int ima_alloc_kexec_file_buf(size_t segment_size) > +{ > + ima_free_kexec_file_buf(&ima_kexec_file); > + > + /* segment size can't change between kexec load and execute */ > + ima_kexec_file.buf = vmalloc(segment_size); > + if (!ima_kexec_file.buf) > + return -ENOMEM; > + > + ima_kexec_file.size = segment_size; > + ima_kexec_file.read_pos = 0; > + ima_kexec_file.count = sizeof(struct ima_kexec_hdr); /* reserved space */ > + > + return 0; > +} > + > 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 ima_kexec_hdr khdr; > int ret = 0; > > /* segment size can't change between kexec load and execute */ > - ima_kexec_file.buf = vmalloc(segment_size); > if (!ima_kexec_file.buf) { > - ret = -ENOMEM; > - goto out; > + pr_err("Kexec file buf not allocated\n"); > + return -EINVAL; > } > > - 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 */ > @@ -71,8 +91,6 @@ static int ima_dump_measurement_list(unsigned long *buffer_size, void **buffer, > *buffer_size = ima_kexec_file.count; > *buffer = ima_kexec_file.buf; > out: > - if (ret == -EINVAL) > - vfree(ima_kexec_file.buf); > return ret; > } > > @@ -111,6 +129,12 @@ void ima_add_kexec_buffer(struct kimage *image) > return; > } > > + ret = ima_alloc_kexec_file_buf(kexec_segment_size); > + if (ret < 0) { > + pr_err("Not enough memory for the kexec measurement buffer.\n"); > + return; > + } > + > ima_dump_measurement_list(&kexec_buffer_size, &kexec_buffer, > kexec_segment_size); > if (!kexec_buffer) { > -- > 2.25.1 >