From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44033) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YYT9q-0007P8-L6 for qemu-devel@nongnu.org; Thu, 19 Mar 2015 01:38:15 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YYT9p-0006FV-SO for qemu-devel@nongnu.org; Thu, 19 Mar 2015 01:38:14 -0400 Received: from mx1.redhat.com ([209.132.183.28]:38670) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YYT9p-0006FQ-NG for qemu-devel@nongnu.org; Thu, 19 Mar 2015 01:38:13 -0400 Date: Thu, 19 Mar 2015 13:26:22 +0800 From: Jason Wang Message-Id: <1426742782.5002.6@smtp.corp.redhat.com> In-Reply-To: <20150318140232-mutt-send-email-mst@redhat.com> References: <1426671309-13645-1-git-send-email-jasowang@redhat.com> <1426671309-13645-8-git-send-email-jasowang@redhat.com> <20150318140232-mutt-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Subject: Re: [Qemu-devel] [PATCH V4 07/19] virtio-net: validate backend queue numbers against bus limitation List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Michael S. Tsirkin" Cc: cornelia.huck@de.ibm.com, qemu-devel@nongnu.org On Wed, Mar 18, 2015 at 9:05 PM, Michael S. Tsirkin wrote: > On Wed, Mar 18, 2015 at 05:34:57PM +0800, Jason Wang wrote: >> We don't validate the backend queue numbers against bus limitation, >> this will easily crash qemu if it exceeds the limitation. Fixing >> this >> by doing the validation and fail early. >> >> Cc: Michael S. Tsirkin >> Signed-off-by: Jason Wang > > Bugfix? needed in 2.3? Yes, a bugfix for the host only support more than 8 tuntap queues. Not sure it was necessary to 2.3. > > >> --- >> hw/net/virtio-net.c | 7 +++++++ >> 1 file changed, 7 insertions(+) >> >> diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c >> index 27adcc5..59f76bc 100644 >> --- a/hw/net/virtio-net.c >> +++ b/hw/net/virtio-net.c >> @@ -1588,6 +1588,13 @@ static void >> virtio_net_device_realize(DeviceState *dev, Error **errp) >> virtio_init(vdev, "virtio-net", VIRTIO_ID_NET, n->config_size); >> >> n->max_queues = MAX(n->nic_conf.peers.queues, 1); >> + if (n->max_queues * 2 + 1 > VIRTIO_PCI_QUEUE_MAX) { > > We have this * 2 + 1 logic in several other places in this file too. > Pls wrap it up in a helper. Ok. > > >> + error_setg(errp, "Invalid number of queues (= %" PRIu32 >> "), " >> + "must be a postive integer less than %d.", >> + n->max_queues, (VIRTIO_PCI_QUEUE_MAX - 1) / 2); >> + virtio_cleanup(vdev); >> + return; >> + } >> n->vqs = g_malloc0(sizeof(VirtIONetQueue) * n->max_queues); >> n->vqs[0].rx_vq = virtio_add_queue(vdev, 256, >> virtio_net_handle_rx); >> n->curr_queues = 1; >> -- >> 2.1.0