[PATCH v5 bpf-next 6/8] bpf: devmap: check XDP features in __xdp_enqueue routine
From: Lorenzo Bianconi <lorenzo@kernel.org>
Date: 2023-02-01 10:25:41
Also in:
bpf, intel-wired-lan
Subsystem:
bpf [general] (safe dynamic programs and tools), bpf [networking] (tcx & tc bpf, sock_addr), networking [general], the rest, xdp (express data path) · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Martin KaFai Lau, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, David S. Miller, Jesper Dangaard Brouer, John Fastabend
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 <redacted> Co-developed-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> --- 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);
--
2.39.1