From patchwork Thu Jul 15 19:32:19 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Thomas Huth X-Patchwork-Id: 1505885 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=Ek5xTo5W; dkim-atps=neutral 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 ozlabs.org (Postfix) with ESMTPS id 4GQkzz23R6z9sS8 for ; Fri, 16 Jul 2021 05:33:03 +1000 (AEST) Received: from localhost ([::1]:55354 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m476T-0001GV-22 for incoming@patchwork.ozlabs.org; Thu, 15 Jul 2021 15:33:01 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:54556) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m4766-0001GD-1S for qemu-devel@nongnu.org; Thu, 15 Jul 2021 15:32:38 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:21965) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m4762-0001GR-7V for qemu-devel@nongnu.org; Thu, 15 Jul 2021 15:32:36 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1626377552; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=vSMFXMNlRRFbjnDQFCNp0/FfqBco0cZ6Rr6PL72tMek=; b=Ek5xTo5WxWS0wxWFS0EJFFjTf8Ptwav2NUgLfQZuVbov6+wYzpyH7fu2yUkFRWp7zZMzBV i/nIYHcae1UFP/m3KDcMX9O2fotXMBh3RkBc88z+iQrwZkRGiXs0nt6PSCnEguMciCYn+5 MmFmmYSGQ2sNr6RGFwGY3GY/QXifKv4= 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-192-hRXmonejN4-6dziP69Qfjg-1; Thu, 15 Jul 2021 15:32:29 -0400 X-MC-Unique: hRXmonejN4-6dziP69Qfjg-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 81832100CA96; Thu, 15 Jul 2021 19:32:23 +0000 (UTC) Received: from thuth.com (ovpn-113-128.ams2.redhat.com [10.36.113.128]) by smtp.corp.redhat.com (Postfix) with ESMTP id 53FBF752A8; Thu, 15 Jul 2021 19:32:22 +0000 (UTC) From: Thomas Huth To: qemu-devel@nongnu.org, Jason Wang , Dmitry Fleytman Subject: [PATCH] hw/net/net_tx_pkt: Fix crash detected by fuzzer Date: Thu, 15 Jul 2021 21:32:19 +0200 Message-Id: <20210715193219.1132571-1-thuth@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=thuth@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=170.10.133.124; envelope-from=thuth@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.698, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no 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: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" QEMU currently crashes when it's started like this: cat << EOF | ./qemu-system-i386 -device vmxnet3 -nodefaults -qtest stdio outl 0xcf8 0x80001014 outl 0xcfc 0xe0001000 outl 0xcf8 0x80001018 outl 0xcf8 0x80001004 outw 0xcfc 0x7 outl 0xcf8 0x80001083 write 0x0 0x1 0xe1 write 0x1 0x1 0xfe write 0x2 0x1 0xbe write 0x3 0x1 0xba writeq 0xe0001020 0xefefff5ecafe0000 writeq 0xe0001020 0xffff5e5ccafe0002 EOF It hits this assertion: qemu-system-i386: ../qemu/hw/net/net_tx_pkt.c:453: net_tx_pkt_reset: Assertion `pkt->raw' failed. This happens because net_tx_pkt_init() is called with max_frags == 0 and thus the allocation p->raw = g_new(struct iovec, max_frags); results in a NULL pointer that cause the assert(pkt->raw); in net_tx_pkt_reset() to fail later. To fix this issue we can check that max_raw_frags was not zero before asserting that pkt->raw is a non-NULL pointer. Buglink: https://bugs.launchpad.net/qemu/+bug/1890157 Signed-off-by: Thomas Huth Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Pankaj Gupta --- hw/net/net_tx_pkt.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/hw/net/net_tx_pkt.c b/hw/net/net_tx_pkt.c index 1f9aa59eca..1cb1125d9f 100644 --- a/hw/net/net_tx_pkt.c +++ b/hw/net/net_tx_pkt.c @@ -450,11 +450,13 @@ void net_tx_pkt_reset(struct NetTxPkt *pkt) pkt->payload_len = 0; pkt->payload_frags = 0; - assert(pkt->raw); - for (i = 0; i < pkt->raw_frags; i++) { - assert(pkt->raw[i].iov_base); - pci_dma_unmap(pkt->pci_dev, pkt->raw[i].iov_base, pkt->raw[i].iov_len, - DMA_DIRECTION_TO_DEVICE, 0); + if (pkt->max_raw_frags > 0) { + assert(pkt->raw); + for (i = 0; i < pkt->raw_frags; i++) { + assert(pkt->raw[i].iov_base); + pci_dma_unmap(pkt->pci_dev, pkt->raw[i].iov_base, + pkt->raw[i].iov_len, DMA_DIRECTION_TO_DEVICE, 0); + } } pkt->raw_frags = 0;