From nobody Mon May 6 21:04:35 2024 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1570735029; cv=none; d=zoho.com; s=zohoarc; b=V+MRn81TGVrFz7fG2XkoxMPgpqkGK1CwYQOVX5LbVRgpvvV1iKrN10bVXRojWegEbVq5gS48aO7GI8Uce74y5w0QTcR+P5xst1p3fEASpydN7Ogr+D4wyN8IvXLdHVN5TPzjS9jqsdiNUFaX/HPK72TObHx95o1/ok/GIwNnyBQ= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1570735029; h=Content-Type:Content-Transfer-Encoding:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To; bh=ul0bPI/F+/OXRASP/F8pWG/G5mqxagozjP3BLSd1AR4=; b=kXDSsUY738RExNuciAVj8p8W6H6rYVCpyF2Sj3Th9iEpOMlGHIj2DshOQHluW6X4vxFVHeuWj9jWLrY5dOz5DNmxhlhzrZNibJKCFtLu4Tqqr3yq7FwwJPRL+GuidOcDMu8sp7f3Y8allQJN235eOgkvvJ6jOt4Ncya/N/QN9KI= ARC-Authentication-Results: i=1; mx.zoho.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1570735029194594.1724581233524; Thu, 10 Oct 2019 12:17:09 -0700 (PDT) Received: from localhost ([::1]:43390 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iIdvq-00023l-3h for importer@patchew.org; Thu, 10 Oct 2019 15:17:02 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:34095) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iIdu3-00015z-Ln for qemu-devel@nongnu.org; Thu, 10 Oct 2019 15:15:12 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iIdu2-00019g-G5 for qemu-devel@nongnu.org; Thu, 10 Oct 2019 15:15:11 -0400 Received: from mx1.redhat.com ([209.132.183.28]:60116) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iIdu2-00019W-Ab for qemu-devel@nongnu.org; Thu, 10 Oct 2019 15:15:10 -0400 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 mx1.redhat.com (Postfix) with ESMTPS id 8154430013A1 for ; Thu, 10 Oct 2019 19:15:09 +0000 (UTC) Received: from gimli.home (ovpn-118-102.phx2.redhat.com [10.3.118.102]) by smtp.corp.redhat.com (Postfix) with ESMTP id 46478100EBD6; Thu, 10 Oct 2019 19:15:05 +0000 (UTC) Subject: [PULL 1/1] hw/vfio/pci: fix double free in vfio_msi_disable From: Alex Williamson To: qemu-devel@nongnu.org Date: Thu, 10 Oct 2019 13:15:04 -0600 Message-ID: <157073488735.23153.15612488542845648378.stgit@gimli.home> In-Reply-To: <157073476983.23153.13333563650903948665.stgit@gimli.home> References: <157073476983.23153.13333563650903948665.stgit@gimli.home> User-Agent: StGit/0.19-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.42]); Thu, 10 Oct 2019 19:15:09 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 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+importer=patchew.org@nongnu.org Sender: "Qemu-devel" From: Evgeny Yakovlev The following guest behaviour patter leads to double free in VFIO PCI: 1. Guest enables MSI interrupts vfio_msi_enable is called, but fails in vfio_enable_vectors. In our case this was because VFIO GPU device was in D3 state. Unhappy path in vfio_msi_enable will g_free(vdev->msi_vectors) but not set this pointer to NULL 2. Guest still sees MSI an enabled after that because emulated config write is done in vfio_pci_write_config unconditionally before calling vfio_msi_enable 3. Guest disables MSI interrupts vfio_msi_disable is called and tries to g_free(vdev->msi_vectors) in vfio_msi_disable_common =3D> double free Signed-off-by: Evgeny Yakovlev Signed-off-by: Alex Williamson --- hw/vfio/pci.c | 1 + 1 file changed, 1 insertion(+) diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c index c5e6fe61cb3e..12fac3980465 100644 --- a/hw/vfio/pci.c +++ b/hw/vfio/pci.c @@ -651,6 +651,7 @@ retry: } =20 g_free(vdev->msi_vectors); + vdev->msi_vectors =3D NULL; =20 if (ret > 0 && ret !=3D vdev->nr_vectors) { vdev->nr_vectors =3D ret;