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=-8.1 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_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 DE623C433DF for ; Wed, 3 Jun 2020 12:52:58 +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 A9E69206C3 for ; Wed, 3 Jun 2020 12:52:58 +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="cUvkn6rM" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A9E69206C3 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]:59564 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jgSt7-0001Rf-V9 for qemu-devel@archiver.kernel.org; Wed, 03 Jun 2020 08:52:57 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:50784) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jgSsZ-00012A-3z for qemu-devel@nongnu.org; Wed, 03 Jun 2020 08:52:23 -0400 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:37034 helo=us-smtp-delivery-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 1jgSsX-00011A-LT for qemu-devel@nongnu.org; Wed, 03 Jun 2020 08:52:22 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591188740; h=from:from:reply-to: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=5IMmT8xbZRf01blFOlI9a0IzwNEj/ImOo7hOJQmMZto=; b=cUvkn6rMFQawY8OtgmwdD0VoMxZ/Jig7iqqNFFjvp3VR/5M+putc1VqX/FcS+m+yEWYbPA psMvxRn6/uCX0brcZjc1zVbsfTUdP94R2AACQjvBL/jfEOVh5Z0WqnKbe5OK0oMyLhIUCw ENCMcLBlINgH7KHWx9czR0+yRVpEcOc= 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-423-dpqpQAzKNKSmNMwlggMpow-1; Wed, 03 Jun 2020 08:52:07 -0400 X-MC-Unique: dpqpQAzKNKSmNMwlggMpow-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 35B471404; Wed, 3 Jun 2020 12:52:06 +0000 (UTC) Received: from redhat.com (unknown [10.36.110.59]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 4ECC1707BA; Wed, 3 Jun 2020 12:52:01 +0000 (UTC) Date: Wed, 3 Jun 2020 13:51:58 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: P J P Subject: Re: [PATCH] pci: check address before reading configuration bytes Message-ID: <20200603125158.GG2892653@redhat.com> References: <20200603124041.1137464-1-ppandit@redhat.com> MIME-Version: 1.0 In-Reply-To: <20200603124041.1137464-1-ppandit@redhat.com> User-Agent: Mutt/1.13.4 (2020-02-15) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Received-SPF: pass client-ip=207.211.31.81; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/06/03 01:12:11 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -10 X-Spam_score: -1.1 X-Spam_bar: - X-Spam_report: (-1.1 / 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, FROM_EXCESS_BASE64=0.979, 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: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Cc: Prasad J Pandit , "Michael S . Tsirkin" , Yi Ren , QEMU Developers , Ren Ding , Hanqing Zhao Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Wed, Jun 03, 2020 at 06:10:41PM +0530, P J P wrote: > From: Prasad J Pandit > > While reading PCI configuration bytes, a guest may send an > address towards the end of the configuration space. It may lead > to an OOB access issue. Add check to ensure 'address + len' is > within PCI configuration space. A malicious guest triggering an OOB access in the host QEMU sounds like a significant security flaw. Do we have a CVE assigned for this ? > > Reported-by: Ren Ding > Reported-by: Hanqing Zhao > Reported-by: Yi Ren > Signed-off-by: Prasad J Pandit > --- > hw/pci/pci.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/hw/pci/pci.c b/hw/pci/pci.c > index 70c66965f5..4429fa9401 100644 > --- a/hw/pci/pci.c > +++ b/hw/pci/pci.c > @@ -1385,7 +1385,9 @@ uint32_t pci_default_read_config(PCIDevice *d, > ranges_overlap(address, len, d->exp.exp_cap + PCI_EXP_LNKSTA, 2)) { > pcie_sync_bridge_lnk(d); > } > - memcpy(&val, d->config + address, len); > + if (address + len <= pci_config_size(d)) { > + memcpy(&val, d->config + address, len); > + } > return le32_to_cpu(val); > } > > -- > 2.26.2 > > Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|