From patchwork Mon Feb 24 06:42:17 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Longpeng(Mike)" X-Patchwork-Id: 11399419 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3C40B14D5 for ; Mon, 24 Feb 2020 06:43:28 +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 1D1B220661 for ; Mon, 24 Feb 2020 06:43:28 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1D1B220661 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Received: from localhost ([::1]:60524 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j67Sh-00080w-Ah for patchwork-qemu-devel@patchwork.kernel.org; Mon, 24 Feb 2020 01:43:27 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:47384) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j67SA-000793-10 for qemu-devel@nongnu.org; Mon, 24 Feb 2020 01:42:54 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1j67S9-0008W6-0f for qemu-devel@nongnu.org; Mon, 24 Feb 2020 01:42:53 -0500 Received: from szxga07-in.huawei.com ([45.249.212.35]:56948 helo=huawei.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1j67S8-0008V3-Lp for qemu-devel@nongnu.org; Mon, 24 Feb 2020 01:42:52 -0500 Received: from DGGEMS405-HUB.china.huawei.com (unknown [172.30.72.60]) by Forcepoint Email with ESMTP id 8754A4B616F13571ED7D; Mon, 24 Feb 2020 14:42:50 +0800 (CST) Received: from DESKTOP-27KDQMV.china.huawei.com (10.173.228.124) by DGGEMS405-HUB.china.huawei.com (10.3.19.205) with Microsoft SMTP Server id 14.3.439.0; Mon, 24 Feb 2020 14:42:39 +0800 From: "Longpeng(Mike)" To: , Subject: [PATCH RESEND 1/3] vfio/pci: fix a null pointer reference in vfio_rom_read Date: Mon, 24 Feb 2020 14:42:17 +0800 Message-ID: <20200224064219.1434-2-longpeng2@huawei.com> X-Mailer: git-send-email 2.25.0.windows.1 In-Reply-To: <20200224064219.1434-1-longpeng2@huawei.com> References: <20200224064219.1434-1-longpeng2@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.173.228.124] X-CFilter-Loop: Reflected X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 45.249.212.35 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: longpeng2@huawei.com, arei.gonglei@huawei.com, huangzhichao@huawei.com, qemu-devel@nongnu.org, weifuqiang@huawei.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" From: Longpeng vfio_pci_load_rom() maybe failed and then the vdev->rom is NULL in some situation (though I've not encountered yet), maybe we should avoid the VM abort. Signed-off-by: Longpeng Reviewed-by: Laszlo Ersek --- hw/vfio/pci.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c index 5e75a95..ed798ae 100644 --- a/hw/vfio/pci.c +++ b/hw/vfio/pci.c @@ -768,7 +768,7 @@ static void vfio_update_msi(VFIOPCIDevice *vdev) } } -static void vfio_pci_load_rom(VFIOPCIDevice *vdev) +static bool vfio_pci_load_rom(VFIOPCIDevice *vdev) { struct vfio_region_info *reg_info; uint64_t size; @@ -778,7 +778,7 @@ static void vfio_pci_load_rom(VFIOPCIDevice *vdev) if (vfio_get_region_info(&vdev->vbasedev, VFIO_PCI_ROM_REGION_INDEX, ®_info)) { error_report("vfio: Error getting ROM info: %m"); - return; + return false; } trace_vfio_pci_load_rom(vdev->vbasedev.name, (unsigned long)reg_info->size, @@ -797,7 +797,7 @@ static void vfio_pci_load_rom(VFIOPCIDevice *vdev) error_printf("Device option ROM contents are probably invalid " "(check dmesg).\nSkip option ROM probe with rombar=0, " "or load from file with romfile=\n"); - return; + return false; } vdev->rom = g_malloc(size); @@ -849,6 +849,8 @@ static void vfio_pci_load_rom(VFIOPCIDevice *vdev) data[6] = -csum; } } + + return true; } static uint64_t vfio_rom_read(void *opaque, hwaddr addr, unsigned size) @@ -863,8 +865,9 @@ static uint64_t vfio_rom_read(void *opaque, hwaddr addr, unsigned size) uint64_t data = 0; /* Load the ROM lazily when the guest tries to read it */ - if (unlikely(!vdev->rom && !vdev->rom_read_failed)) { - vfio_pci_load_rom(vdev); + if (unlikely(!vdev->rom && !vdev->rom_read_failed) && + !vfio_pci_load_rom(vdev)) { + return 0; } memcpy(&val, vdev->rom + addr,