From cc5b5d3565048ae57d14e5674a5fb085b2ab0193 Mon Sep 17 00:00:00 2001 From: Krzysztof Kazimierczak Date: Thu, 10 Jan 2019 20:29:02 +0100 Subject: xsk: Check if a queue exists during umem setup MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In the xdp_umem_assign_dev() path, the xsk code does not check if a queue for which umem is to be created exists. It leads to a situation where umem is not assigned to any Tx/Rx queue of a netdevice, without notifying the stack about an error. This affects both XDP_SKB and XDP_DRV modes - in case of XDP_DRV_ZC, queue index is checked by the driver. This patch fixes xsk code, so that in both XDP_SKB and XDP_DRV mode of AF_XDP, an error is returned when requested queue index exceedes an existing maximum. Fixes: c9b47cc1fabca ("xsk: fix bug when trying to use both copy and zero-copy on one queue id") Reported-by: Jakub Spizewski Signed-off-by: Krzysztof Kazimierczak Acked-by: Björn Töpel Signed-off-by: Daniel Borkmann --- net/xdp/xdp_umem.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) (limited to 'net/xdp') diff --git a/net/xdp/xdp_umem.c b/net/xdp/xdp_umem.c index a264cf2accd0..d4de871e7d4d 100644 --- a/net/xdp/xdp_umem.c +++ b/net/xdp/xdp_umem.c @@ -41,13 +41,20 @@ void xdp_del_sk_umem(struct xdp_umem *umem, struct xdp_sock *xs) * not know if the device has more tx queues than rx, or the opposite. * This might also change during run time. */ -static void xdp_reg_umem_at_qid(struct net_device *dev, struct xdp_umem *umem, - u16 queue_id) +static int xdp_reg_umem_at_qid(struct net_device *dev, struct xdp_umem *umem, + u16 queue_id) { + if (queue_id >= max_t(unsigned int, + dev->real_num_rx_queues, + dev->real_num_tx_queues)) + return -EINVAL; + if (queue_id < dev->real_num_rx_queues) dev->_rx[queue_id].umem = umem; if (queue_id < dev->real_num_tx_queues) dev->_tx[queue_id].umem = umem; + + return 0; } struct xdp_umem *xdp_get_umem_from_qid(struct net_device *dev, @@ -88,7 +95,10 @@ int xdp_umem_assign_dev(struct xdp_umem *umem, struct net_device *dev, goto out_rtnl_unlock; } - xdp_reg_umem_at_qid(dev, umem, queue_id); + err = xdp_reg_umem_at_qid(dev, umem, queue_id); + if (err) + goto out_rtnl_unlock; + umem->dev = dev; umem->queue_id = queue_id; if (force_copy) -- cgit v1.2.3-59-g8ed1b