From 01d76b5317003e019ace561a9b775f51aafdfdc4 Mon Sep 17 00:00:00 2001 From: Ilya Maximets Date: Fri, 7 Jun 2019 20:27:32 +0300 Subject: [PATCH] xdp: check device pointer before clearing We should not call 'ndo_bpf()' or 'dev_put()' with NULL argument. Fixes: c9b47cc1fabc ("xsk: fix bug when trying to use both copy and zero-copy on one queue id") Signed-off-by: Ilya Maximets Acked-by: Jonathan Lemon Signed-off-by: Daniel Borkmann --- net/xdp/xdp_umem.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/net/xdp/xdp_umem.c b/net/xdp/xdp_umem.c index 2b18223..9c6de4f 100644 --- a/net/xdp/xdp_umem.c +++ b/net/xdp/xdp_umem.c @@ -143,6 +143,9 @@ static void xdp_umem_clear_dev(struct xdp_umem *umem) struct netdev_bpf bpf; int err; + if (!umem->dev) + return; + if (umem->zc) { bpf.command = XDP_SETUP_XSK_UMEM; bpf.xsk.umem = NULL; @@ -156,11 +159,9 @@ static void xdp_umem_clear_dev(struct xdp_umem *umem) WARN(1, "failed to disable umem!\n"); } - if (umem->dev) { - rtnl_lock(); - xdp_clear_umem_at_qid(umem->dev, umem->queue_id); - rtnl_unlock(); - } + rtnl_lock(); + xdp_clear_umem_at_qid(umem->dev, umem->queue_id); + rtnl_unlock(); if (umem->zc) { dev_put(umem->dev); -- 2.7.4