From nobody Sun Feb 8 19:39:43 2026 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=1563802941; cv=none; d=zoho.com; s=zohoarc; b=jAg35k1LRYic8QM98BzqsCfIe+45TrucnWNFa9y0FszrSiMKxdb/hofPBQjS7ZJwOOUo+5iVr/ET0mgHBJ6OjdNuzYrdQdYYeCCEaMlDvIYCgH/RSUkWo3wqazhZaKZzVatYtlVQeaJRjKCIt6V17GQDyhyILo2/LGW5QzANKb4= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1563802941; h=Content-Transfer-Encoding:Cc: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:ARC-Authentication-Results; bh=netB7Ev/yCvL8eKNvzZQjL0qEn5Nfgl2GanLTMAIOZw=; b=K86ne98qoVzLXSes0u/ZFRAQxrfyvllwnQdqDwBxwmK6QB6ojiCl6lzxJPTb/x8ovSu3A2GEPm4WUYyUnhE2XFFV2vFvywiA5sNGGQpkZsl0bVFTL3LeeYQOHSnc6z7kxrJOX0N+CBUl5Tb5t0w/OosnkHPwGrMZR1kf/NYFRtA= 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 1563802941198651.3138871309654; Mon, 22 Jul 2019 06:42:21 -0700 (PDT) Received: from localhost ([::1]:33742 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hpYa3-0002L2-Mz for importer@patchew.org; Mon, 22 Jul 2019 09:42:19 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:54632) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hpYZ9-0007Xl-Dw for qemu-devel@nongnu.org; Mon, 22 Jul 2019 09:41:24 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hpYZ8-0005CY-9L for qemu-devel@nongnu.org; Mon, 22 Jul 2019 09:41:23 -0400 Received: from mx1.redhat.com ([209.132.183.28]:59772) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hpYZ8-0005Br-49; Mon, 22 Jul 2019 09:41:22 -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 68AE43082131; Mon, 22 Jul 2019 13:41:21 +0000 (UTC) Received: from t460s.redhat.com (ovpn-116-75.ams2.redhat.com [10.36.116.75]) by smtp.corp.redhat.com (Postfix) with ESMTP id B204E101F97D; Mon, 22 Jul 2019 13:41:19 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Date: Mon, 22 Jul 2019 15:41:03 +0200 Message-Id: <20190722134108.22151-2-david@redhat.com> In-Reply-To: <20190722134108.22151-1-david@redhat.com> References: <20190722134108.22151-1-david@redhat.com> MIME-Version: 1.0 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]); Mon, 22 Jul 2019 13:41:21 +0000 (UTC) Content-Transfer-Encoding: quoted-printable 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-for-4.1 v3 1/6] virtio-balloon: Fix wrong sign extension of PFNs 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: "Michael S . Tsirkin" , David Hildenbrand , qemu-stable@nongnu.org, Stefan Hajnoczi , Igor Mammedov , David Gibson Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Type: text/plain; charset="utf-8" If we directly cast from int to uint64_t, we will first sign-extend to an int64_t, which is wrong. We actually want to treat the PFNs like unsigned values. As far as I can see, this dates back to the initial virtio-balloon commit, but wasn't triggered as fairly big guests would be required. Cc: qemu-stable@nongnu.org Reported-by: Michael S. Tsirkin Signed-off-by: David Hildenbrand Reviewed-by: David Gibson --- hw/virtio/virtio-balloon.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c index e85d1c0d5c..515abf6553 100644 --- a/hw/virtio/virtio-balloon.c +++ b/hw/virtio/virtio-balloon.c @@ -343,8 +343,8 @@ static void virtio_balloon_handle_output(VirtIODevice *= vdev, VirtQueue *vq) } =20 while (iov_to_buf(elem->out_sg, elem->out_num, offset, &pfn, 4) = =3D=3D 4) { + unsigned int p =3D virtio_ldl_p(vdev, &pfn); hwaddr pa; - int p =3D virtio_ldl_p(vdev, &pfn); =20 pa =3D (hwaddr) p << VIRTIO_BALLOON_PFN_SHIFT; offset +=3D 4; --=20 2.21.0