From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D6FC2C433EF for ; Mon, 13 Sep 2021 05:54:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B6B9260E76 for ; Mon, 13 Sep 2021 05:54:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237171AbhIMFzo (ORCPT ); Mon, 13 Sep 2021 01:55:44 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:52987 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230390AbhIMFzn (ORCPT ); Mon, 13 Sep 2021 01:55:43 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1631512468; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=JVcoRs6vCll2DBs4INaAB12noZulXuAcHA8wZRFtb1U=; b=QyJLW6ThrytGYLpwGIE2bg3F5cC0GRBwQwbTUZqA1rkjo3VLTYv4jDXIWkQ39IBZ1VecEZ onqWvr4LVYEnOJq4+dMSUnVYrUkrI7oZ2/cC/a5eINFh6525cJOaxmILXL0kb3zNJpAJCw ffajBQEV/psbWVBxQ/OO+e1dGUsSw9g= 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-491-OS7aoxwvNNiFl-nb5TlXsQ-1; Mon, 13 Sep 2021 01:54:23 -0400 X-MC-Unique: OS7aoxwvNNiFl-nb5TlXsQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 04001800FF3; Mon, 13 Sep 2021 05:54:22 +0000 (UTC) Received: from localhost.localdomain (ovpn-13-146.pek2.redhat.com [10.72.13.146]) by smtp.corp.redhat.com (Postfix) with ESMTP id 6AF7C5C23A; Mon, 13 Sep 2021 05:54:11 +0000 (UTC) From: Jason Wang To: mst@redhat.com, jasowang@redhat.com Cc: virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org, f.hetzelt@tu-berlin.de, david.kaplan@amd.com, konrad.wilk@oracle.com, Paolo Bonzini , Stefan Hajnoczi Subject: [PATCH 1/9] virtio-blk: validate num_queues during probe Date: Mon, 13 Sep 2021 13:53:45 +0800 Message-Id: <20210913055353.35219-2-jasowang@redhat.com> In-Reply-To: <20210913055353.35219-1-jasowang@redhat.com> References: <20210913055353.35219-1-jasowang@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If an untrusted device neogitates BLK_F_MQ but advertises a zero num_queues, the driver may end up trying to allocating zero size buffers where ZERO_SIZE_PTR is returned which may pass the checking against the NULL. This will lead unexpected results. Fixing this by using single queue if num_queues is zero. Cc: Paolo Bonzini Cc: Stefan Hajnoczi Signed-off-by: Jason Wang --- drivers/block/virtio_blk.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index e574fbf5e6df..f130d12df4b9 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -498,7 +498,8 @@ static int init_vq(struct virtio_blk *vblk) err = virtio_cread_feature(vdev, VIRTIO_BLK_F_MQ, struct virtio_blk_config, num_queues, &num_vqs); - if (err) + /* We need at least on virtqueue */ + if (err || !num_vqs) num_vqs = 1; num_vqs = min_t(unsigned int, nr_cpu_ids, num_vqs); -- 2.25.1