From patchwork Thu Sep 1 11:00:51 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Prasad Pandit X-Patchwork-Id: 9308837 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 9416C607D6 for ; Thu, 1 Sep 2016 11:01:39 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8527B292EC for ; Thu, 1 Sep 2016 11:01:39 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 77E44292F7; Thu, 1 Sep 2016 11:01:39 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id D878E292EC for ; Thu, 1 Sep 2016 11:01:34 +0000 (UTC) Received: from localhost ([::1]:36241 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bfPkT-0002lS-5L for patchwork-qemu-devel@patchwork.kernel.org; Thu, 01 Sep 2016 07:01:33 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53748) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bfPk0-0002fi-1P for qemu-devel@nongnu.org; Thu, 01 Sep 2016 07:01:08 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bfPju-0004yO-S6 for qemu-devel@nongnu.org; Thu, 01 Sep 2016 07:01:03 -0400 Received: from mx1.redhat.com ([209.132.183.28]:41948) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bfPju-0004y5-Jm for qemu-devel@nongnu.org; Thu, 01 Sep 2016 07:00:58 -0400 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id A9A4143A3B; Thu, 1 Sep 2016 11:00:57 +0000 (UTC) Received: from javelin.localdomain (vpn1-6-107.ams2.redhat.com [10.36.6.107]) by int-mx14.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u81B0qnp012644 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Thu, 1 Sep 2016 07:00:54 -0400 From: P J P To: Qemu Developers Date: Thu, 1 Sep 2016 16:30:51 +0530 Message-Id: <1472727651-18938-1-git-send-email-ppandit@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.27 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Thu, 01 Sep 2016 11:00:57 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v3] scsi: check page count while initialising descriptor rings X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Dmitry Fleytman , Paolo Bonzini , Tom Victor , Prasad J Pandit , Li Qiang Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP From: Prasad J Pandit Vmware Paravirtual SCSI emulation uses command descriptors to process SCSI commands. These descriptors come with their ring buffers. A guest could set the page count for these rings to an arbitrary value, leading to infinite loop or OOB access. Add check to avoid it. Reported-by: Tom Victor Reported-by: Li Qiang Signed-off-by: Prasad J Pandit Reviewed-by: Dmitry Fleytman --- hw/scsi/vmw_pvscsi.c | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-) Update per review -> https://lists.gnu.org/archive/html/qemu-devel/2016-09/msg00019.html diff --git a/hw/scsi/vmw_pvscsi.c b/hw/scsi/vmw_pvscsi.c index 5116f4a..4245c15 100644 --- a/hw/scsi/vmw_pvscsi.c +++ b/hw/scsi/vmw_pvscsi.c @@ -152,7 +152,7 @@ pvscsi_log2(uint32_t input) return log; } -static int +static void pvscsi_ring_init_data(PVSCSIRingInfo *m, PVSCSICmdDescSetupRings *ri) { int i; @@ -160,10 +160,6 @@ pvscsi_ring_init_data(PVSCSIRingInfo *m, PVSCSICmdDescSetupRings *ri) uint32_t req_ring_size, cmp_ring_size; m->rs_pa = ri->ringsStatePPN << VMW_PAGE_SHIFT; - if ((ri->reqRingNumPages > PVSCSI_SETUP_RINGS_MAX_NUM_PAGES) - || (ri->cmpRingNumPages > PVSCSI_SETUP_RINGS_MAX_NUM_PAGES)) { - return -1; - } req_ring_size = ri->reqRingNumPages * PVSCSI_MAX_NUM_REQ_ENTRIES_PER_PAGE; cmp_ring_size = ri->cmpRingNumPages * PVSCSI_MAX_NUM_CMP_ENTRIES_PER_PAGE; txr_len_log2 = pvscsi_log2(req_ring_size - 1); @@ -195,8 +191,6 @@ pvscsi_ring_init_data(PVSCSIRingInfo *m, PVSCSICmdDescSetupRings *ri) /* Flush ring state page changes */ smp_wmb(); - - return 0; } static int @@ -746,7 +740,7 @@ pvscsi_dbg_dump_tx_rings_config(PVSCSICmdDescSetupRings *rc) trace_pvscsi_tx_rings_num_pages("Confirm Ring", rc->cmpRingNumPages); for (i = 0; i < rc->cmpRingNumPages; i++) { - trace_pvscsi_tx_rings_ppn("Confirm Ring", rc->reqRingPPNs[i]); + trace_pvscsi_tx_rings_ppn("Confirm Ring", rc->cmpRingPPNs[i]); } } @@ -779,10 +773,15 @@ pvscsi_on_cmd_setup_rings(PVSCSIState *s) trace_pvscsi_on_cmd_arrived("PVSCSI_CMD_SETUP_RINGS"); + if (!rc->reqRingNumPages + || rc->reqRingNumPages > PVSCSI_SETUP_RINGS_MAX_NUM_PAGES + || !rc->cmpRingNumPages + || rc->cmpRingNumPages > PVSCSI_SETUP_RINGS_MAX_NUM_PAGES) { + return PVSCSI_COMMAND_PROCESSING_FAILED; + } + pvscsi_dbg_dump_tx_rings_config(rc); - if (pvscsi_ring_init_data(&s->rings, rc) < 0) { - return PVSCSI_COMMAND_PROCESSING_FAILED; - } + pvscsi_ring_init_data(&s->rings, rc); s->rings_info_valid = TRUE; return PVSCSI_COMMAND_PROCESSING_SUCCEEDED;