From 2632b09ea3e8de57f754b25f64bfbf87e71f47ff Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Mon, 20 Nov 2017 15:21:55 -0800 Subject: [PATCH] net: xdp: don't allow device-bound programs in driver mode Currently device-bound programs are not able to run on the host to save resources (host JIT is not invoked). Don't allow XDP programs to be attached without the HW_MODE flag. In theory if program is already translated for device offload the driver should choose to offload it instead of loading it in the driver. However, offloading translated program may still fail resulting in device-bound program being run on the host. Prevent this by refusing to attach device bound programs if XDP_FLAGS_HW_MODE is not set. Signed-off-by: Jakub Kicinski Reviewed-by: Quentin Monnet Acked-by: Alexei Starovoitov Acked-by: Daniel Borkmann Signed-off-by: Daniel Borkmann --- net/core/dev.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/net/core/dev.c b/net/core/dev.c index 09525a27319c7..5e2ba133fba7e 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -7143,6 +7143,13 @@ int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack, bpf_op == ops->ndo_bpf); if (IS_ERR(prog)) return PTR_ERR(prog); + + if (!(flags & XDP_FLAGS_HW_MODE) && + bpf_prog_is_dev_bound(prog->aux)) { + NL_SET_ERR_MSG(extack, "using device-bound program without HW_MODE flag is not supported"); + bpf_prog_put(prog); + return -EINVAL; + } } err = dev_xdp_install(dev, bpf_op, extack, flags, prog); -- 2.39.5