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=-4.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLACK,URIBL_BLOCKED autolearn=no 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 F150AC433DF for ; Tue, 26 May 2020 20:45:08 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B3241207CB for ; Tue, 26 May 2020 20:45:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="bhmJG+xl" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B3241207CB Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:43812 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jdgRf-0006AJ-UG for qemu-devel@archiver.kernel.org; Tue, 26 May 2020 16:45:07 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:36246) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jdgQT-0005AC-8J for qemu-devel@nongnu.org; Tue, 26 May 2020 16:43:53 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:31003 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1jdgQR-0007Rt-RP for qemu-devel@nongnu.org; Tue, 26 May 2020 16:43:52 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1590525829; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=MqwAiWPvkyWeTuHOgcPlU8vd9VeflHy8pmTYV2+LUFg=; b=bhmJG+xlLplIdXLGzMPJ7WWYwWNHVzcXzPoEOYoeXx6eUFlgo4Oq8kfCP076/+z+ZJ1K5Y vj6ask0n+NgwIadm4tH2papRGKGhcXf+YkDe3hOgEK9f89H1ZM335uMFtANZv8gmSzRFLV XY/7K0WXxaoDNU5IcZIyovlDR5/Kzeo= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-28-mdOunh_FOOKYqNqQXAbX2A-1; Tue, 26 May 2020 16:43:45 -0400 X-MC-Unique: mdOunh_FOOKYqNqQXAbX2A-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A3AFF18017E5; Tue, 26 May 2020 20:43:44 +0000 (UTC) Received: from x1.home (ovpn-114-203.phx2.redhat.com [10.3.114.203]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1DD5310013D7; Tue, 26 May 2020 20:43:44 +0000 (UTC) Date: Tue, 26 May 2020 14:43:43 -0600 From: Alex Williamson To: Leonardo Bras Subject: Re: [RESEND PATCH 1/1] vfio/nvlink: Remove exec permission to avoid SELinux AVCs Message-ID: <20200526144343.7c6c6def@x1.home> In-Reply-To: <8f5ae1658103b71b09555d3ab499edaf3f36a15d.camel@gmail.com> References: <8f5ae1658103b71b09555d3ab499edaf3f36a15d.camel@gmail.com> Organization: Red Hat MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=205.139.110.120; envelope-from=alex.williamson@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/05/26 15:25:01 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001 autolearn=_AUTOLEARN X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Alexey Kardashevskiy , dgibson@redhat.com, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Mon, 18 May 2020 12:05:24 -0300 Leonardo Bras wrote: > If SELinux is setup without 'execmem' permission for qemu, all mmap > with (PROT_WRITE | PROT_EXEC) will fail and print a warning in > SELinux log. > > If "nvlink2-mr" memory allocation fails (fist diff), it will cause > guest NUMA nodes to not be correctly configured (V100 memory will > not be visible for guest, nor its NUMA nodes). > > Not having 'execmem' permission is intesting for virtual machines to > avoid buffer-overflow based attacks, and it's adopted in distros > like RHEL. > > So, removing the PROT_EXEC flag seems the right thing to do. > > Browsing some other code that mmaps memory for usage with > memory_region_init_ram_device_ptr, I could notice it's usual to > not have PROT_EXEC (only PROT_READ | PROT_WRITE), so it should be > no problem around this. > > Signed-off-by: Leonardo Bras > Reviewed-by: Alexey Kardashevskiy > > --- Seems David Gibson might be in a position to send a pull request including this before I can, so: Acked-by: Alex Williamson > - Alexey's review is here: https://lists.nongnu.org/archive/html/qemu-devel/2020-05/msg00006.html > > hw/vfio/pci-quirks.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/hw/vfio/pci-quirks.c b/hw/vfio/pci-quirks.c > index 2d348f8237..124d4f57e1 100644 > --- a/hw/vfio/pci-quirks.c > +++ b/hw/vfio/pci-quirks.c > @@ -1620,7 +1620,7 @@ int vfio_pci_nvidia_v100_ram_init(VFIOPCIDevice *vdev, Error **errp) > } > cap = (void *) hdr; > > - p = mmap(NULL, nv2reg->size, PROT_READ | PROT_WRITE | PROT_EXEC, > + p = mmap(NULL, nv2reg->size, PROT_READ | PROT_WRITE, > MAP_SHARED, vdev->vbasedev.fd, nv2reg->offset); > if (p == MAP_FAILED) { > ret = -errno; > @@ -1680,7 +1680,7 @@ int vfio_pci_nvlink2_init(VFIOPCIDevice *vdev, Error **errp) > > /* Some NVLink bridges may not have assigned ATSD */ > if (atsdreg->size) { > - p = mmap(NULL, atsdreg->size, PROT_READ | PROT_WRITE | PROT_EXEC, > + p = mmap(NULL, atsdreg->size, PROT_READ | PROT_WRITE, > MAP_SHARED, vdev->vbasedev.fd, atsdreg->offset); > if (p == MAP_FAILED) { > ret = -errno; >