From b9d460c9245541b13de2369e79688f8e0acc0c3d Mon Sep 17 00:00:00 2001 From: Lorenzo Bianconi Date: Wed, 1 Feb 2023 11:24:22 +0100 Subject: [PATCH] bpf: devmap: check XDP features in __xdp_enqueue routine Check if the destination device implements ndo_xdp_xmit callback relying on NETDEV_XDP_ACT_NDO_XMIT flags. Moreover, check if the destination device supports XDP non-linear frame in __xdp_enqueue and is_valid_dst routines. This patch allows to perform XDP_REDIRECT on non-linear XDP buffers. Acked-by: Jesper Dangaard Brouer Co-developed-by: Kumar Kartikeya Dwivedi Signed-off-by: Kumar Kartikeya Dwivedi Signed-off-by: Lorenzo Bianconi Link: https://lore.kernel.org/r/26a94c33520c0bfba021b3fbb2cb8c1e69bf53b8.1675245258.git.lorenzo@kernel.org Signed-off-by: Alexei Starovoitov --- kernel/bpf/devmap.c | 16 +++++++++++++--- net/core/filter.c | 13 +++++-------- 2 files changed, 18 insertions(+), 11 deletions(-) diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c index d01e4c55b376..2675fefc6cb6 100644 --- a/kernel/bpf/devmap.c +++ b/kernel/bpf/devmap.c @@ -474,7 +474,11 @@ static inline int __xdp_enqueue(struct net_device *dev, struct xdp_frame *xdpf, { int err; - if (!dev->netdev_ops->ndo_xdp_xmit) + if (!(dev->xdp_features & NETDEV_XDP_ACT_NDO_XMIT)) + return -EOPNOTSUPP; + + if (unlikely(!(dev->xdp_features & NETDEV_XDP_ACT_NDO_XMIT_SG) && + xdp_frame_has_frags(xdpf))) return -EOPNOTSUPP; err = xdp_ok_fwd_dev(dev, xdp_get_frame_len(xdpf)); @@ -532,8 +536,14 @@ int dev_map_enqueue(struct bpf_dtab_netdev *dst, struct xdp_frame *xdpf, static bool is_valid_dst(struct bpf_dtab_netdev *obj, struct xdp_frame *xdpf) { - if (!obj || - !obj->dev->netdev_ops->ndo_xdp_xmit) + if (!obj) + return false; + + if (!(obj->dev->xdp_features & NETDEV_XDP_ACT_NDO_XMIT)) + return false; + + if (unlikely(!(obj->dev->xdp_features & NETDEV_XDP_ACT_NDO_XMIT_SG) && + xdp_frame_has_frags(xdpf))) return false; if (xdp_ok_fwd_dev(obj->dev, xdp_get_frame_len(xdpf))) diff --git a/net/core/filter.c b/net/core/filter.c index 0039cf16713e..2ce06a72a5ba 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -4318,16 +4318,13 @@ int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp, struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); enum bpf_map_type map_type = ri->map_type; - /* XDP_REDIRECT is not fully supported yet for xdp frags since - * not all XDP capable drivers can map non-linear xdp_frame in - * ndo_xdp_xmit. - */ - if (unlikely(xdp_buff_has_frags(xdp) && - map_type != BPF_MAP_TYPE_CPUMAP)) - return -EOPNOTSUPP; + if (map_type == BPF_MAP_TYPE_XSKMAP) { + /* XDP_REDIRECT is not supported AF_XDP yet. */ + if (unlikely(xdp_buff_has_frags(xdp))) + return -EOPNOTSUPP; - if (map_type == BPF_MAP_TYPE_XSKMAP) return __xdp_do_redirect_xsk(ri, dev, xdp, xdp_prog); + } return __xdp_do_redirect_frame(ri, dev, xdp_convert_buff_to_frame(xdp), xdp_prog); -- 2.25.1