From 509ca545d425512f83ca70093f6d836ec8ab5bd1 Mon Sep 17 00:00:00 2001 From: Jordan Rife Date: Thu, 18 Jun 2026 11:20:32 -0700 Subject: bpf: Support BPF_F_EGRESS with bpf_redirect_peer We have several use cases where a pod injects traffic into the datapath of another so that the traffic appears to have originated from that pod. One such use case is a synthetic flow generator which injects synthetic traffic into a pod's datapath to enable dynamic probing and debugging. Another is a transparent proxy where connections originating from one pod are redirected towards another which proxies that connection. The new connection is bound to the IP of the original pod using IP_TRANSPARENT and its traffic is injected into that pod's datapath and handled as if it had originated there. This can be used for mTLS, etc. We use bpf_redirect(BPF_F_INGRESS) to direct traffic leaving the proxy, flow generator, etc. towards the target pod, ensuring that eBPF programs that are meant to intercept traffic leaving that pod are executed. However, this doesn't work with netkit. With netkit, an ingress redirection from proxy to workload skips eBPF programs that are meant to intercept traffic leaving the pod, since they reside on the netkit peer device. One workaround is to attach the same program to both the netkit peer device and the TCX ingress hook for the netkit pair's primary interface, but a) This seems hacky and we need to be careful not to run the same program twice for the same skb in cases where we want to pass that traffic to the host stack. b) We're trying to keep the proxy redirection / traffic injection systems as modular and separated from Cilium as possible, the system that manages netkit setup and core eBPF programming. It would be handy if instead we could redirect traffic directly from one netkit peer device to another. This patch proposes an extension to bpf_redirect_peer to allow us to do just that. With this patch, the BPF_F_EGRESS flag tells bpf_redirect_peer to emit the skb in the egress direction of the target interface's peer device While the main use case is netkit, I suppose you could also use this mode with veth as well if, e.g., there were some eBPF programs attached to that side of the veth pair that needed to intercept traffic. +---------------------------------------------------------------------+ | +-------------------------+ 6. bpf_redirect_neigh(eth0) | | | pod (10.244.0.10) | ------------------------ | | | | | | | | | +--------+ | | +---------+ | | | | 1. packet -->| | | | | | | | | | leaves ^ | netkit |<===========|======| netkit | | | | | | | peer |=======(eBPF)=====>| primary | | | | | | | | | | | | | | | | | +--------+ | | +---------+ | | | | | | | 2. bpf_redirect v | | +-----------|-------------+ |___________________ +-------| | | | | eth0 | | | 5. bpf_redirect_peer(BPF_F_EGRESS) | +-------| | |________________________ | | | +-------------------------+ | | | | | proxy (10.244.0.11) | | | | | | IP_TRANSPARENT | | | | | | +--------+ | | +---------+ | | | | 3. packet <--| | | | | |<-- | | | enters | netkit |<===========|======| netkit | | | | [proxy] | peer |=======(eBPF)=====>| primary | | | | 4. packet -->| | | | | | | | leaves +--------+ | +---------+ | | | sip=10.244.0.10 | | | +-------------------------+ | +---------------------------------------------------------------------+ Using the proxy use case as an example, in step 5 we would redirect traffic leaving the proxy towards the pod's peer device using bpf_redirect_peer(BPF_F_EGRESS). As a bonus, since the skb doesn't have to go through the backlog queue it can take full advantage of netkit's performance benefits. I set up a test where outgoing iperf3 traffic is injected into the datapath of another pod using either bpf_redirect_peer(BPF_F_EGRESS) or bpf_redirect(BPF_F_INGRESS). I used Cilium's eBPF host routing mode which skips the host stack and uses BPF redirect helpers to do all the routing. (net.ipv4.tcp_congestion_control=cubic,mtu=1500,100GiB link,Cilium eBPF host routing mode) BASELINE [bpf_redirect(BPF_F_INGRESS)] 1. [iperf pod] ==bpf_redirect([pod b], BPF_F_INGRESS)==> [pod b] 2. [pod b] ==bpf_redirect_neigh([eth0])==> eth0 3. eth0 ==over network==> [host b] [ ID] Interval Transfer Bitrate Retr [ 5] 0.00-60.00 sec 231 GBytes 33.0 Gbits/sec 12060 sender [ 5] 0.00-60.00 sec 230 GBytes 33.0 Gbits/sec receiver TEST [bpf_redirect_peer(BPF_F_EGRESS)] 1. [iperf pod] ==bpf_redirect_peer([pod b], BPF_F_EGRESS)==> [pod b] 2. [pod b] ==bpf_redirect_neigh([eth0])==> eth0 3. eth0 ==over network==> [host b] [ ID] Interval Transfer Bitrate Retr [ 5] 0.00-60.00 sec 272 GBytes 38.9 Gbits/sec 0 sender [ 5] 0.00-60.00 sec 272 GBytes 38.9 Gbits/sec receiver In this test, using bpf_redirect_peer(BPF_F_EGRESS) for the hop from [iperf pod] to [pod b] led to ~18% more throughput compared to bpf_redirect(BPF_F_INGRESS). Signed-off-by: Jordan Rife Acked-by: Daniel Borkmann Acked-by: Paul Chaignon Reviewed-by: Jiayuan Chen Link: https://lore.kernel.org/r/20260618182035.43811-2-jordan@jrife.io Signed-off-by: Alexei Starovoitov --- tools/include/uapi/linux/bpf.h | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) (limited to 'tools/include/uapi') diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 89b36de5fdbb..c91b5a4bda03 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -5079,17 +5079,19 @@ union bpf_attr { * Description * Redirect the packet to another net device of index *ifindex*. * This helper is somewhat similar to **bpf_redirect**\ (), except - * that the redirection happens to the *ifindex*' peer device and - * the netns switch takes place from ingress to ingress without - * going through the CPU's backlog queue. + * that the redirection happens to the *ifindex*' peer device. If + * *flags* is 0, the netns switch takes place from ingress to + * ingress without going through the CPU's backlog queue. If the + * **BPF_F_EGRESS** flag is provided then redirection happens in + * the egress direction of the peer device. * * *skb*\ **->mark** and *skb*\ **->tstamp** are not cleared during * the netns switch. * - * The *flags* argument is reserved and must be 0. The helper is - * currently only supported for tc BPF program types at the - * ingress hook and for veth and netkit target device types. The - * peer device must reside in a different network namespace. + * If the *flags* argument is 0, the helper is currently only + * supported for tc BPF program types at the ingress hook and for + * veth and netkit target device types. The peer device must reside + * in a different network namespace. * Return * The helper returns **TC_ACT_REDIRECT** on success or * **TC_ACT_SHOT** on error. @@ -6336,9 +6338,10 @@ enum { /* Flags for bpf_redirect and bpf_redirect_map helpers */ enum { BPF_F_INGRESS = (1ULL << 0), /* used for skb path */ + BPF_F_EGRESS = (1ULL << 1), /* used for skb path */ BPF_F_BROADCAST = (1ULL << 3), /* used for XDP path */ BPF_F_EXCLUDE_INGRESS = (1ULL << 4), /* used for XDP path */ -#define BPF_F_REDIRECT_FLAGS (BPF_F_INGRESS | BPF_F_BROADCAST | BPF_F_EXCLUDE_INGRESS) +#define BPF_F_REDIRECT_FLAGS (BPF_F_INGRESS | BPF_F_EGRESS | BPF_F_BROADCAST | BPF_F_EXCLUDE_INGRESS) }; #define __bpf_md_ptr(type, name) \ -- cgit From 859055e07697c46f6964109981aa1cd23d6bde47 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Mon, 29 Jun 2026 23:22:06 +0200 Subject: bpf: Add tracing_multi link info support Adding BPF_OBJ_GET_INFO_BY_FD support for tracing_multi links. We expose following tracing_multi link data: - attach_type of the program - number of ids - array of BTF ids - array of its related kernel addresses - array of cookies The change follows the kprobe_multi and uprobe_multi link-info convention of optional output arrays with an in/out count, On top of standard tracing link data we also expose addresses, because they are useful info for user (especially when the attachment was done via pattern). This data is hidden when kallsyms does not allow exposing kernel pointer values. Assisted-by: Codex:GPT-5 Signed-off-by: Jiri Olsa Signed-off-by: Andrii Nakryiko Acked-by: Leon Hwang Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20260629212208.895962-2-jolsa@kernel.org --- include/uapi/linux/bpf.h | 9 +++++++ kernel/trace/bpf_trace.c | 55 ++++++++++++++++++++++++++++++++++++++++++ tools/include/uapi/linux/bpf.h | 9 +++++++ 3 files changed, 73 insertions(+) (limited to 'tools/include/uapi') diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index c91b5a4bda03..2f1d24fef857 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -6842,6 +6842,15 @@ struct bpf_link_info { __u32 flags; __u32 pid; } uprobe_multi; + struct { + __u32 attach_type; + __u32 count; /* in/out: tracing_multi target count */ + __u32 btf_obj_id; + __u32 :32; + __aligned_u64 ids; + __aligned_u64 addrs; + __aligned_u64 cookies; + } tracing_multi; struct { __u32 type; /* enum bpf_perf_event_type */ __u32 :32; diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 75495a5c3507..76ab51deaa6b 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -3700,6 +3700,60 @@ static void bpf_tracing_multi_link_dealloc(struct bpf_link *link) kvfree(tr_link); } +static int bpf_tracing_multi_link_fill_link_info(const struct bpf_link *link, + struct bpf_link_info *info) +{ + u64 __user *ucookies = u64_to_user_ptr(info->tracing_multi.cookies); + u64 __user *uaddrs = u64_to_user_ptr(info->tracing_multi.addrs); + u32 __user *uids = u64_to_user_ptr(info->tracing_multi.ids); + struct bpf_tracing_multi_link *tr_link; + u32 ucount = info->tracing_multi.count; + bool has_cookies, show_addrs; + int err = 0; + + if ((uids || ucookies || uaddrs) && !ucount) + return -EINVAL; + + tr_link = container_of(link, struct bpf_tracing_multi_link, link); + + info->tracing_multi.attach_type = tr_link->link.attach_type; + info->tracing_multi.count = tr_link->nodes_cnt; + info->tracing_multi.btf_obj_id = btf_obj_id(tr_link->link.prog->aux->attach_btf); + + if (!uids && !ucookies && !uaddrs) + return 0; + + if (ucount < tr_link->nodes_cnt) + err = -ENOSPC; + else + ucount = tr_link->nodes_cnt; + + has_cookies = !!tr_link->cookies; + show_addrs = kallsyms_show_value(current_cred()); + + for (int i = 0; i < ucount; i++) { + struct bpf_tracing_multi_node *mnode = &tr_link->nodes[i]; + u64 addr, cookie; + u32 id; + + bpf_trampoline_unpack_key(mnode->trampoline->key, NULL, &id); + + addr = show_addrs ? mnode->trampoline->ip : 0; + cookie = has_cookies ? tr_link->cookies[i] : 0; + + if (uids && put_user(id, uids + i)) + return -EFAULT; + if (uaddrs && put_user(addr, uaddrs + i)) + return -EFAULT; + if (ucookies && put_user(cookie, ucookies + i)) + return -EFAULT; + + cond_resched(); + } + + return err; +} + #ifdef CONFIG_PROC_FS static void bpf_tracing_multi_show_fdinfo(const struct bpf_link *link, struct seq_file *seq) @@ -3730,6 +3784,7 @@ static void bpf_tracing_multi_show_fdinfo(const struct bpf_link *link, static const struct bpf_link_ops bpf_tracing_multi_link_lops = { .release = bpf_tracing_multi_link_release, .dealloc_deferred = bpf_tracing_multi_link_dealloc, + .fill_link_info = bpf_tracing_multi_link_fill_link_info, #ifdef CONFIG_PROC_FS .show_fdinfo = bpf_tracing_multi_show_fdinfo, #endif diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index c91b5a4bda03..2f1d24fef857 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -6842,6 +6842,15 @@ struct bpf_link_info { __u32 flags; __u32 pid; } uprobe_multi; + struct { + __u32 attach_type; + __u32 count; /* in/out: tracing_multi target count */ + __u32 btf_obj_id; + __u32 :32; + __aligned_u64 ids; + __aligned_u64 addrs; + __aligned_u64 cookies; + } tracing_multi; struct { __u32 type; /* enum bpf_perf_event_type */ __u32 :32; -- cgit From 35dac1daeb3c8208515047d32f22c4a162e8de5f Mon Sep 17 00:00:00 2001 From: Avinash Duduskar Date: Mon, 13 Jul 2026 21:53:03 +0530 Subject: bpf: Add BPF_FIB_LOOKUP_VLAN flag to bpf_fib_lookup() helper MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit bpf_fib_lookup() returns the FIB-resolved egress ifindex straight from the fib result. When the egress is a VLAN device, the returned ifindex is the VLAN netdev's, which has no XDP xmit handler; XDP programs that want to forward the frame (e.g. xdp-forward) must instead target the underlying physical device and push the VLAN tag themselves. Today the program has no way to learn either the underlying ifindex or the VLAN tag without maintaining its own VLAN-to-ifindex map in userspace and refreshing it on netlink events. Add BPF_FIB_LOOKUP_VLAN. When the caller sets this flag and the fib result is a VLAN device whose immediate parent is a real (non-VLAN) device in the same network namespace, populate the existing output fields params->h_vlan_proto and params->h_vlan_TCI from the VLAN device and replace params->ifindex with the parent's ifindex. params->h_vlan_TCI carries the VID only, with PCP and DEI bits zero; a consumer wanting to set egress priority writes PCP itself. params->smac is the VLAN device's own address, which can differ from the parent's. Only the immediate parent is resolved, via vlan_dev_priv(dev)->real_dev and not vlan_dev_real_dev(), which walks to the bottom of a stack. When the immediate parent is not a real device in the same namespace, the lookup returns BPF_FIB_LKUP_RET_VLAN_FAILURE and leaves params->ifindex at the input. This covers a stacked VLAN (QinQ), where the immediate parent is itself a VLAN device and one h_vlan_proto/h_vlan_TCI pair cannot describe two tags, and a parent in another network namespace (a VLAN device can be moved while its parent stays), whose ifindex would be meaningless in the caller's namespace. A program that wants the VLAN device's own ifindex re-issues the lookup, with a re-initialized params, without BPF_FIB_LOOKUP_VLAN, so the unreducible case stays distinct from a physical egress. That distinction matters for XDP: a program cannot xmit on a VLAN device, so a success carrying the VLAN ifindex would make it redirect to a device with no ndo_xdp_xmit and drop the frame at xdp_do_flush(). The swap and the vlan fields are written only on the reduce path; other output fields keep their existing behaviour, so a frag-needed result still reports the route mtu in params->mtu_result. BPF_FIB_LOOKUP_VLAN is only useful to XDP, which cannot redirect to a VLAN device. A tc program can redirect to the VLAN device directly, so bpf_skb_fib_lookup() rejects the flag with -EINVAL; bpf_xdp_fib_lookup() accepts it. When the flag is not set, behaviour is unchanged: h_vlan_proto and h_vlan_TCI are zeroed and ifindex is left at the FIB result. The new block is compiled only under CONFIG_VLAN_8021Q since vlan_dev_priv() is not defined otherwise; without that config is_vlan_dev() is constant false and the flag is accepted but never acts. That is safe because no VLAN device can exist there, so every egress is already physical. This lets an XDP redirect target the physical device and learn the tag to push in a single lookup, which xdp-forward's optional VLAN mode (xdp-project/xdp-tools#504) wants from the kernel side. The helper's input semantics are unchanged; the reverse direction (supplying a tag as lookup input) is added in the following patch. Suggested-by: Toke Høiland-Jørgensen Signed-off-by: Avinash Duduskar Reviewed-by: Toke Høiland-Jørgensen Reviewed-by: Emil Tsalapatis Acked-by: David Ahern Link: https://lore.kernel.org/bpf/20260713162305.1237211-2-avinash.duduskar@gmail.com Signed-off-by: Kumar Kartikeya Dwivedi --- include/uapi/linux/bpf.h | 33 ++++++++++++++++++++++++++++++++- net/core/filter.c | 33 +++++++++++++++++++++++++++++---- tools/include/uapi/linux/bpf.h | 33 ++++++++++++++++++++++++++++++++- 3 files changed, 93 insertions(+), 6 deletions(-) (limited to 'tools/include/uapi') diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 2f1d24fef857..8b41c365ddf9 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -3532,6 +3532,31 @@ union bpf_attr { * Use the mark present in *params*->mark for the fib lookup. * This option should not be used with BPF_FIB_LOOKUP_DIRECT, * as it only has meaning for full lookups. + * **BPF_FIB_LOOKUP_VLAN** + * If the fib lookup resolves to a VLAN device whose + * parent is a real (non-VLAN) device, set + * *params*->h_vlan_proto and *params*->h_vlan_TCI from + * the VLAN device and replace *params*->ifindex with the + * parent's ifindex. *params*->h_vlan_TCI carries the VID + * only, with PCP and DEI bits zero; a consumer wanting to + * set egress priority writes PCP itself. *params*->smac is + * the VLAN device's own address, which can differ from the + * parent's. Only the immediate parent is resolved; if it + * is itself a VLAN device (QinQ) or in another namespace, + * the egress cannot be reduced to a physical device plus + * one tag and the lookup returns + * **BPF_FIB_LKUP_RET_VLAN_FAILURE** with *params*->ifindex + * left at the input. To obtain the VLAN device's own + * ifindex, repeat the lookup without + * **BPF_FIB_LOOKUP_VLAN**, re-initializing *params* + * first: output fields overwrite the inputs they share + * storage with. The swap and the vlan fields + * are written only on success; other output fields keep + * the helper's existing behaviour, so a frag-needed result + * still reports the route mtu in *params*->mtu_result. + * This flag is only valid for XDP programs; tc programs + * receive -EINVAL since they can redirect to the VLAN + * device directly. * * *ctx* is either **struct xdp_md** for XDP programs or * **struct sk_buff** tc cls_act programs. @@ -7339,6 +7364,7 @@ enum { BPF_FIB_LOOKUP_TBID = (1U << 3), BPF_FIB_LOOKUP_SRC = (1U << 4), BPF_FIB_LOOKUP_MARK = (1U << 5), + BPF_FIB_LOOKUP_VLAN = (1U << 6), }; enum { @@ -7352,6 +7378,7 @@ enum { BPF_FIB_LKUP_RET_NO_NEIGH, /* no neighbor entry for nh */ BPF_FIB_LKUP_RET_FRAG_NEEDED, /* fragmentation required to fwd */ BPF_FIB_LKUP_RET_NO_SRC_ADDR, /* failed to derive IP src addr */ + BPF_FIB_LKUP_RET_VLAN_FAILURE, /* VLAN egress, parent unresolvable */ }; struct bpf_fib_lookup { @@ -7405,7 +7432,11 @@ struct bpf_fib_lookup { union { struct { - /* output */ + /* + * output with BPF_FIB_LOOKUP_VLAN: set from the + * resolved egress VLAN device (see the flag); zeroed + * on other successful lookups. + */ __be16 h_vlan_proto; __be16 h_vlan_TCI; }; diff --git a/net/core/filter.c b/net/core/filter.c index 056deb9b3fc3..b8f2595ff582 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -6206,10 +6206,29 @@ static const struct bpf_func_proto bpf_skb_get_xfrm_state_proto = { #endif #if IS_ENABLED(CONFIG_INET) || IS_ENABLED(CONFIG_IPV6) -static int bpf_fib_set_fwd_params(struct bpf_fib_lookup *params, u32 mtu) +static int bpf_fib_set_fwd_params(struct net_device *dev, + struct bpf_fib_lookup *params, + u32 flags, u32 mtu, u32 in_ifindex) { params->h_vlan_TCI = 0; params->h_vlan_proto = 0; + +#if IS_ENABLED(CONFIG_VLAN_8021Q) + if ((flags & BPF_FIB_LOOKUP_VLAN) && is_vlan_dev(dev)) { + struct net_device *real_dev = vlan_dev_priv(dev)->real_dev; + + if (!is_vlan_dev(real_dev) && + net_eq(dev_net(real_dev), dev_net(dev))) { + params->h_vlan_proto = vlan_dev_vlan_proto(dev); + params->h_vlan_TCI = htons(vlan_dev_vlan_id(dev)); + params->ifindex = real_dev->ifindex; + } else { + params->ifindex = in_ifindex; + return BPF_FIB_LKUP_RET_VLAN_FAILURE; + } + } +#endif + if (mtu) params->mtu_result = mtu; /* union with tot_len */ @@ -6221,6 +6240,7 @@ static int bpf_fib_set_fwd_params(struct bpf_fib_lookup *params, u32 mtu) static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params, u32 flags, bool check_mtu) { + u32 in_ifindex = params->ifindex; struct neighbour *neigh = NULL; struct fib_nh_common *nhc; struct in_device *in_dev; @@ -6352,7 +6372,7 @@ static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params, memcpy(params->smac, dev->dev_addr, ETH_ALEN); set_fwd_params: - return bpf_fib_set_fwd_params(params, mtu); + return bpf_fib_set_fwd_params(dev, params, flags, mtu, in_ifindex); } #endif @@ -6362,6 +6382,7 @@ static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params, { struct in6_addr *src = (struct in6_addr *) params->ipv6_src; struct in6_addr *dst = (struct in6_addr *) params->ipv6_dst; + u32 in_ifindex = params->ifindex; struct fib6_result res = {}; struct neighbour *neigh; struct net_device *dev; @@ -6491,13 +6512,14 @@ static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params, memcpy(params->smac, dev->dev_addr, ETH_ALEN); set_fwd_params: - return bpf_fib_set_fwd_params(params, mtu); + return bpf_fib_set_fwd_params(dev, params, flags, mtu, in_ifindex); } #endif #define BPF_FIB_LOOKUP_MASK (BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_OUTPUT | \ BPF_FIB_LOOKUP_SKIP_NEIGH | BPF_FIB_LOOKUP_TBID | \ - BPF_FIB_LOOKUP_SRC | BPF_FIB_LOOKUP_MARK) + BPF_FIB_LOOKUP_SRC | BPF_FIB_LOOKUP_MARK | \ + BPF_FIB_LOOKUP_VLAN) BPF_CALL_4(bpf_xdp_fib_lookup, struct xdp_buff *, ctx, struct bpf_fib_lookup *, params, int, plen, u32, flags) @@ -6546,6 +6568,9 @@ BPF_CALL_4(bpf_skb_fib_lookup, struct sk_buff *, skb, if (flags & ~BPF_FIB_LOOKUP_MASK) return -EINVAL; + if (flags & BPF_FIB_LOOKUP_VLAN) + return -EINVAL; + if (params->tot_len) check_mtu = true; diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 2f1d24fef857..8b41c365ddf9 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -3532,6 +3532,31 @@ union bpf_attr { * Use the mark present in *params*->mark for the fib lookup. * This option should not be used with BPF_FIB_LOOKUP_DIRECT, * as it only has meaning for full lookups. + * **BPF_FIB_LOOKUP_VLAN** + * If the fib lookup resolves to a VLAN device whose + * parent is a real (non-VLAN) device, set + * *params*->h_vlan_proto and *params*->h_vlan_TCI from + * the VLAN device and replace *params*->ifindex with the + * parent's ifindex. *params*->h_vlan_TCI carries the VID + * only, with PCP and DEI bits zero; a consumer wanting to + * set egress priority writes PCP itself. *params*->smac is + * the VLAN device's own address, which can differ from the + * parent's. Only the immediate parent is resolved; if it + * is itself a VLAN device (QinQ) or in another namespace, + * the egress cannot be reduced to a physical device plus + * one tag and the lookup returns + * **BPF_FIB_LKUP_RET_VLAN_FAILURE** with *params*->ifindex + * left at the input. To obtain the VLAN device's own + * ifindex, repeat the lookup without + * **BPF_FIB_LOOKUP_VLAN**, re-initializing *params* + * first: output fields overwrite the inputs they share + * storage with. The swap and the vlan fields + * are written only on success; other output fields keep + * the helper's existing behaviour, so a frag-needed result + * still reports the route mtu in *params*->mtu_result. + * This flag is only valid for XDP programs; tc programs + * receive -EINVAL since they can redirect to the VLAN + * device directly. * * *ctx* is either **struct xdp_md** for XDP programs or * **struct sk_buff** tc cls_act programs. @@ -7339,6 +7364,7 @@ enum { BPF_FIB_LOOKUP_TBID = (1U << 3), BPF_FIB_LOOKUP_SRC = (1U << 4), BPF_FIB_LOOKUP_MARK = (1U << 5), + BPF_FIB_LOOKUP_VLAN = (1U << 6), }; enum { @@ -7352,6 +7378,7 @@ enum { BPF_FIB_LKUP_RET_NO_NEIGH, /* no neighbor entry for nh */ BPF_FIB_LKUP_RET_FRAG_NEEDED, /* fragmentation required to fwd */ BPF_FIB_LKUP_RET_NO_SRC_ADDR, /* failed to derive IP src addr */ + BPF_FIB_LKUP_RET_VLAN_FAILURE, /* VLAN egress, parent unresolvable */ }; struct bpf_fib_lookup { @@ -7405,7 +7432,11 @@ struct bpf_fib_lookup { union { struct { - /* output */ + /* + * output with BPF_FIB_LOOKUP_VLAN: set from the + * resolved egress VLAN device (see the flag); zeroed + * on other successful lookups. + */ __be16 h_vlan_proto; __be16 h_vlan_TCI; }; -- cgit From 217828aad80d091fa1d840587a3d9b6187ee170f Mon Sep 17 00:00:00 2001 From: Avinash Duduskar Date: Mon, 13 Jul 2026 21:53:04 +0530 Subject: bpf: Add BPF_FIB_LOOKUP_VLAN_INPUT flag to bpf_fib_lookup() helper MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit BPF_FIB_LOOKUP_VLAN resolves a VLAN egress. The reverse is also useful: an XDP program receiving a VLAN-tagged frame on a physical device wants the lookup to behave as if the packet had arrived on the corresponding VLAN subinterface, so iif-based policy routing and VRF table selection use the right ingress. Add BPF_FIB_LOOKUP_VLAN_INPUT. When set, params->h_vlan_proto and params->h_vlan_TCI are read as an input VLAN tag and the matching VLAN device of params->ifindex is resolved with __vlan_find_dev_deep_rcu(). The device must be up and in the same network namespace as params->ifindex (a VLAN device can be moved to another netns while registered on its parent; receive would deliver into that other namespace, which a lookup here cannot represent). If params->ifindex is itself a VLAN device, its inner (QinQ) subinterface is matched. For a bond or team, a tag on a port matches no device and returns NOT_FWDED; pass the master's ifindex. The lookup then runs with the resolved device as the ingress; params->ifindex itself is not modified on the input side. When the resolved device is enslaved to a VRF, both the full lookup (via the l3mdev rule) and BPF_FIB_LOOKUP_DIRECT (via l3mdev_fib_table_rcu()) select the VRF's table from the resolved ingress. That follows from feeding the resolved device to the flow as the ingress (fl4.flowi4_iif = dev->ifindex), which is what makes l3mdev resolve the VRF master from the subinterface rather than from params->ifindex. The two failure classes get different treatment on purpose. A h_vlan_proto other than 802.1Q/802.1ad is API misuse and returns -EINVAL, since it would otherwise reach the WARN in vlan_proto_idx() with a program-controlled value. An unmatched VID, a device that is down, or one in another namespace is a data outcome and returns BPF_FIB_LKUP_RET_NOT_FWDED, matching the DIRECT path when fib_get_table() finds no table and mirroring real ingress, where the receive path drops such frames. A VID of 0 (a priority tag) is looked up literally and normally fails the same way; receive instead processes such frames untagged, so callers should not set the flag for priority tags. Proceeding on the physical device for any of these would be fail-open for the policy-routing cases above. The h_vlan fields share a union with tbid, so the flag cannot be combined with BPF_FIB_LOOKUP_TBID. It describes ingress, so it also cannot be combined with BPF_FIB_LOOKUP_OUTPUT. Both combinations return -EINVAL; restricting now keeps a later relaxation backward compatible. Combining with BPF_FIB_LOOKUP_VLAN is allowed: the tag is consumed on the ingress side and the egress tag is written on success. Under !CONFIG_VLAN_8021Q the __vlan_find_dev_deep_rcu() stub returns NULL, so every lookup with a valid proto returns NOT_FWDED, which is correct since no VLAN device can exist. Suggested-by: Toke Høiland-Jørgensen Signed-off-by: Avinash Duduskar Reviewed-by: Toke Høiland-Jørgensen Reviewed-by: Emil Tsalapatis Link: https://lore.kernel.org/bpf/20260713162305.1237211-3-avinash.duduskar@gmail.com Signed-off-by: Kumar Kartikeya Dwivedi --- include/uapi/linux/bpf.h | 21 +++++++++++++- net/core/filter.c | 66 ++++++++++++++++++++++++++++++++++++++---- tools/include/uapi/linux/bpf.h | 21 +++++++++++++- 3 files changed, 101 insertions(+), 7 deletions(-) (limited to 'tools/include/uapi') diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 8b41c365ddf9..005038fbeea4 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -3557,6 +3557,22 @@ union bpf_attr { * This flag is only valid for XDP programs; tc programs * receive -EINVAL since they can redirect to the VLAN * device directly. + * **BPF_FIB_LOOKUP_VLAN_INPUT** + * Treat *params*->h_vlan_proto and *params*->h_vlan_TCI + * as an input VLAN tag and run the lookup as if ingress + * had happened on the VLAN subinterface carrying that tag + * on *params*->ifindex. The VID is the low 12 bits of + * *params*->h_vlan_TCI; *params*->h_vlan_proto must be + * ETH_P_8021Q or ETH_P_8021AD in network byte order, else + * **-EINVAL**. If *params*->ifindex is itself a VLAN + * device, its inner (QinQ) subinterface is matched; for a + * bond or team, pass the master's ifindex. An unmatched + * tag, a down device, or one in another namespace returns + * **BPF_FIB_LKUP_RET_NOT_FWDED**, mirroring real ingress. + * A VID of 0 is looked up literally, so do not set this + * flag for priority-tagged frames. Cannot be combined with + * **BPF_FIB_LOOKUP_TBID** or **BPF_FIB_LOOKUP_OUTPUT** + * (returns **-EINVAL**). * * *ctx* is either **struct xdp_md** for XDP programs or * **struct sk_buff** tc cls_act programs. @@ -7365,6 +7381,7 @@ enum { BPF_FIB_LOOKUP_SRC = (1U << 4), BPF_FIB_LOOKUP_MARK = (1U << 5), BPF_FIB_LOOKUP_VLAN = (1U << 6), + BPF_FIB_LOOKUP_VLAN_INPUT = (1U << 7), }; enum { @@ -7435,7 +7452,9 @@ struct bpf_fib_lookup { /* * output with BPF_FIB_LOOKUP_VLAN: set from the * resolved egress VLAN device (see the flag); zeroed - * on other successful lookups. + * on other successful lookups. input with + * BPF_FIB_LOOKUP_VLAN_INPUT: the VLAN tag to scope + * the lookup by. */ __be16 h_vlan_proto; __be16 h_vlan_TCI; diff --git a/net/core/filter.c b/net/core/filter.c index b8f2595ff582..0b7afdd0ae47 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -6234,6 +6234,25 @@ static int bpf_fib_set_fwd_params(struct net_device *dev, return 0; } + +static struct net_device *bpf_fib_vlan_input_dev(struct net_device *dev, + const struct bpf_fib_lookup *params) +{ + __be16 proto = params->h_vlan_proto; + struct net_device *vlan_dev; + u16 vid; + + if (proto != htons(ETH_P_8021Q) && proto != htons(ETH_P_8021AD)) + return ERR_PTR(-EINVAL); + + vid = ntohs(params->h_vlan_TCI) & VLAN_VID_MASK; + vlan_dev = __vlan_find_dev_deep_rcu(dev, proto, vid); + if (!vlan_dev || !(vlan_dev->flags & IFF_UP) || + !net_eq(dev_net(vlan_dev), dev_net(dev))) + return NULL; + + return vlan_dev; +} #endif #if IS_ENABLED(CONFIG_INET) @@ -6254,6 +6273,14 @@ static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params, if (unlikely(!dev)) return -ENODEV; + if (flags & BPF_FIB_LOOKUP_VLAN_INPUT) { + dev = bpf_fib_vlan_input_dev(dev, params); + if (IS_ERR(dev)) + return PTR_ERR(dev); + if (!dev) + return BPF_FIB_LKUP_RET_NOT_FWDED; + } + /* verify forwarding is enabled on this interface */ in_dev = __in_dev_get_rcu(dev); if (unlikely(!in_dev || !IN_DEV_FORWARD(in_dev))) @@ -6263,7 +6290,11 @@ static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params, fl4.flowi4_iif = 1; fl4.flowi4_oif = params->ifindex; } else { - fl4.flowi4_iif = params->ifindex; + /* + * dev->ifindex, not params->ifindex: VLAN_INPUT may have + * resolved dev to a subinterface above. + */ + fl4.flowi4_iif = dev->ifindex; fl4.flowi4_oif = 0; } fl4.flowi4_dscp = inet_dsfield_to_dscp(params->tos); @@ -6400,6 +6431,14 @@ static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params, if (unlikely(!dev)) return -ENODEV; + if (flags & BPF_FIB_LOOKUP_VLAN_INPUT) { + dev = bpf_fib_vlan_input_dev(dev, params); + if (IS_ERR(dev)) + return PTR_ERR(dev); + if (!dev) + return BPF_FIB_LKUP_RET_NOT_FWDED; + } + idev = __in6_dev_get_safely(dev); if (unlikely(!idev || !READ_ONCE(idev->cnf.forwarding))) return BPF_FIB_LKUP_RET_FWD_DISABLED; @@ -6408,7 +6447,12 @@ static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params, fl6.flowi6_iif = 1; oif = fl6.flowi6_oif = params->ifindex; } else { - oif = fl6.flowi6_iif = params->ifindex; + /* + * dev->ifindex, not params->ifindex: VLAN_INPUT may have + * resolved dev to a subinterface above. + */ + oif = dev->ifindex; + fl6.flowi6_iif = oif; fl6.flowi6_oif = 0; strict = RT6_LOOKUP_F_HAS_SADDR; } @@ -6519,7 +6563,19 @@ set_fwd_params: #define BPF_FIB_LOOKUP_MASK (BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_OUTPUT | \ BPF_FIB_LOOKUP_SKIP_NEIGH | BPF_FIB_LOOKUP_TBID | \ BPF_FIB_LOOKUP_SRC | BPF_FIB_LOOKUP_MARK | \ - BPF_FIB_LOOKUP_VLAN) + BPF_FIB_LOOKUP_VLAN | BPF_FIB_LOOKUP_VLAN_INPUT) + +static bool bpf_fib_lookup_flags_ok(u32 flags) +{ + if (flags & ~BPF_FIB_LOOKUP_MASK) + return false; + + if ((flags & BPF_FIB_LOOKUP_VLAN_INPUT) && + (flags & (BPF_FIB_LOOKUP_TBID | BPF_FIB_LOOKUP_OUTPUT))) + return false; + + return true; +} BPF_CALL_4(bpf_xdp_fib_lookup, struct xdp_buff *, ctx, struct bpf_fib_lookup *, params, int, plen, u32, flags) @@ -6527,7 +6583,7 @@ BPF_CALL_4(bpf_xdp_fib_lookup, struct xdp_buff *, ctx, if (plen < sizeof(*params)) return -EINVAL; - if (flags & ~BPF_FIB_LOOKUP_MASK) + if (!bpf_fib_lookup_flags_ok(flags)) return -EINVAL; switch (params->family) { @@ -6565,7 +6621,7 @@ BPF_CALL_4(bpf_skb_fib_lookup, struct sk_buff *, skb, if (plen < sizeof(*params)) return -EINVAL; - if (flags & ~BPF_FIB_LOOKUP_MASK) + if (!bpf_fib_lookup_flags_ok(flags)) return -EINVAL; if (flags & BPF_FIB_LOOKUP_VLAN) diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 8b41c365ddf9..005038fbeea4 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -3557,6 +3557,22 @@ union bpf_attr { * This flag is only valid for XDP programs; tc programs * receive -EINVAL since they can redirect to the VLAN * device directly. + * **BPF_FIB_LOOKUP_VLAN_INPUT** + * Treat *params*->h_vlan_proto and *params*->h_vlan_TCI + * as an input VLAN tag and run the lookup as if ingress + * had happened on the VLAN subinterface carrying that tag + * on *params*->ifindex. The VID is the low 12 bits of + * *params*->h_vlan_TCI; *params*->h_vlan_proto must be + * ETH_P_8021Q or ETH_P_8021AD in network byte order, else + * **-EINVAL**. If *params*->ifindex is itself a VLAN + * device, its inner (QinQ) subinterface is matched; for a + * bond or team, pass the master's ifindex. An unmatched + * tag, a down device, or one in another namespace returns + * **BPF_FIB_LKUP_RET_NOT_FWDED**, mirroring real ingress. + * A VID of 0 is looked up literally, so do not set this + * flag for priority-tagged frames. Cannot be combined with + * **BPF_FIB_LOOKUP_TBID** or **BPF_FIB_LOOKUP_OUTPUT** + * (returns **-EINVAL**). * * *ctx* is either **struct xdp_md** for XDP programs or * **struct sk_buff** tc cls_act programs. @@ -7365,6 +7381,7 @@ enum { BPF_FIB_LOOKUP_SRC = (1U << 4), BPF_FIB_LOOKUP_MARK = (1U << 5), BPF_FIB_LOOKUP_VLAN = (1U << 6), + BPF_FIB_LOOKUP_VLAN_INPUT = (1U << 7), }; enum { @@ -7435,7 +7452,9 @@ struct bpf_fib_lookup { /* * output with BPF_FIB_LOOKUP_VLAN: set from the * resolved egress VLAN device (see the flag); zeroed - * on other successful lookups. + * on other successful lookups. input with + * BPF_FIB_LOOKUP_VLAN_INPUT: the VLAN tag to scope + * the lookup by. */ __be16 h_vlan_proto; __be16 h_vlan_TCI; -- cgit From f68df52fbad0928f4686f734827e5fb6b20386ad Mon Sep 17 00:00:00 2001 From: Jianlin Shi Date: Mon, 13 Jul 2026 10:49:01 +0800 Subject: docs: bpf: Document BPF_RB_OVERWRITE_POS in bpf_ringbuf_query BPF_RB_OVERWRITE_POS is supported by bpf_ringbuf_query() but was missing from the helper documentation. Add it to the flags list in both the kernel UAPI header and its tools/ mirror. Signed-off-by: Jianlin Shi Acked-by: Xu Kuohai Link: https://lore.kernel.org/bpf/tencent_22134645443B75ED907D2A85A47AD554A709@qq.com Signed-off-by: Kumar Kartikeya Dwivedi --- include/uapi/linux/bpf.h | 1 + tools/include/uapi/linux/bpf.h | 1 + 2 files changed, 2 insertions(+) (limited to 'tools/include/uapi') diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 005038fbeea4..ffd96e8b920b 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -4735,6 +4735,7 @@ union bpf_attr { * * **BPF_RB_RING_SIZE**: The size of ring buffer. * * **BPF_RB_CONS_POS**: Consumer position (can wrap around). * * **BPF_RB_PROD_POS**: Producer(s) position (can wrap around). + * * **BPF_RB_OVERWRITE_POS**: Overwrite position (can wrap around). * * Data returned is just a momentary snapshot of actual values * and could be inaccurate, so this facility should be used to diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 005038fbeea4..ffd96e8b920b 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -4735,6 +4735,7 @@ union bpf_attr { * * **BPF_RB_RING_SIZE**: The size of ring buffer. * * **BPF_RB_CONS_POS**: Consumer position (can wrap around). * * **BPF_RB_PROD_POS**: Producer(s) position (can wrap around). + * * **BPF_RB_OVERWRITE_POS**: Overwrite position (can wrap around). * * Data returned is just a momentary snapshot of actual values * and could be inaccurate, so this facility should be used to -- cgit From 5e4bcad6171d4baf426e49a39580cdb79254ea36 Mon Sep 17 00:00:00 2001 From: Nick Hudson Date: Wed, 12 Aug 2026 09:31:10 +0100 Subject: bpf: Name the enum for BPF_FUNC_skb_adjust_room flags The existing anonymous enum for BPF_FUNC_skb_adjust_room flags is named to enum bpf_adj_room_flags to enable CO-RE (Compile Once - Run Everywhere) lookups in BPF programs. Co-developed-by: Max Tottenham Co-developed-by: Anna Glasgall Signed-off-by: Max Tottenham Signed-off-by: Anna Glasgall Signed-off-by: Nick Hudson Signed-off-by: Daniel Borkmann Reviewed-by: Willem de Bruijn Link: https://lore.kernel.org/bpf/20260812083115.73100-2-nhudson@akamai.com --- include/uapi/linux/bpf.h | 2 +- tools/include/uapi/linux/bpf.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'tools/include/uapi') diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index ffd96e8b920b..f6c9dc856858 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -6283,7 +6283,7 @@ enum { }; /* BPF_FUNC_skb_adjust_room flags. */ -enum { +enum bpf_adj_room_flags { BPF_F_ADJ_ROOM_FIXED_GSO = (1ULL << 0), BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 = (1ULL << 1), BPF_F_ADJ_ROOM_ENCAP_L3_IPV6 = (1ULL << 2), diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index ffd96e8b920b..f6c9dc856858 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -6283,7 +6283,7 @@ enum { }; /* BPF_FUNC_skb_adjust_room flags. */ -enum { +enum bpf_adj_room_flags { BPF_F_ADJ_ROOM_FIXED_GSO = (1ULL << 0), BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 = (1ULL << 1), BPF_F_ADJ_ROOM_ENCAP_L3_IPV6 = (1ULL << 2), -- cgit From da199070bc6209bf5db970f8f84c7db4210fe511 Mon Sep 17 00:00:00 2001 From: Nick Hudson Date: Wed, 12 Aug 2026 09:31:12 +0100 Subject: bpf: Add BPF_F_ADJ_ROOM_DECAP_* flags for tunnel decapsulation Add new bpf_skb_adjust_room() decapsulation flags: - BPF_F_ADJ_ROOM_DECAP_L4_GRE - BPF_F_ADJ_ROOM_DECAP_L4_UDP - BPF_F_ADJ_ROOM_DECAP_IPXIP4 - BPF_F_ADJ_ROOM_DECAP_IPXIP6 These flags let BPF programs describe which tunnel layer is being removed, so later changes can update tunnel-related GSO state accordingly during decapsulation. This patch only introduces the UAPI flag definitions and helper documentation. Co-developed-by: Max Tottenham Co-developed-by: Anna Glasgall Signed-off-by: Max Tottenham Signed-off-by: Anna Glasgall Signed-off-by: Nick Hudson Signed-off-by: Daniel Borkmann Reviewed-by: Willem de Bruijn Link: https://lore.kernel.org/bpf/20260812083115.73100-4-nhudson@akamai.com --- include/uapi/linux/bpf.h | 34 ++++++++++++++++++++++++++++++++-- tools/include/uapi/linux/bpf.h | 34 ++++++++++++++++++++++++++++++++-- 2 files changed, 64 insertions(+), 4 deletions(-) (limited to 'tools/include/uapi') diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index f6c9dc856858..732b35cc08d1 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -3038,8 +3038,34 @@ union bpf_attr { * * * **BPF_F_ADJ_ROOM_DECAP_L3_IPV4**, * **BPF_F_ADJ_ROOM_DECAP_L3_IPV6**: - * Indicate the new IP header version after decapsulating the outer - * IP header. Used when the inner and outer IP versions are different. + * Indicate the new IP header version after decapsulating the + * outer IP header. Used when the inner and outer IP versions + * are different. These flags only trigger a protocol change + * without clearing any tunnel-specific GSO flags. + * + * * **BPF_F_ADJ_ROOM_DECAP_L4_GRE**: + * Clear GRE tunnel GSO flags (SKB_GSO_GRE and SKB_GSO_GRE_CSUM) + * when decapsulating a GRE tunnel. + * + * * **BPF_F_ADJ_ROOM_DECAP_L4_UDP**: + * Clear UDP tunnel GSO flags (SKB_GSO_UDP_TUNNEL and + * SKB_GSO_UDP_TUNNEL_CSUM) when decapsulating a UDP tunnel. + * + * * **BPF_F_ADJ_ROOM_DECAP_IPXIP4**: + * Clear IPIP/SIT tunnel GSO flag (SKB_GSO_IPXIP4) when decapsulating + * a tunnel with an outer IPv4 header (IPv4-in-IPv4 or IPv6-in-IPv4). + * + * * **BPF_F_ADJ_ROOM_DECAP_IPXIP6**: + * Clear IPv6 encapsulation tunnel GSO flag (SKB_GSO_IPXIP6) when + * decapsulating a tunnel with an outer IPv6 header (IPv6-in-IPv6 + * or IPv4-in-IPv6). + * + * When using the decapsulation flags above, the skb->encapsulation + * flag is automatically cleared if all tunnel-specific GSO flags + * (SKB_GSO_UDP_TUNNEL, SKB_GSO_UDP_TUNNEL_CSUM, SKB_GSO_GRE, + * SKB_GSO_GRE_CSUM, SKB_GSO_IPXIP4, SKB_GSO_IPXIP6) have been + * removed from the packet. This handles cases where all tunnel + * layers have been decapsulated. * * A call to this helper is susceptible to change the underlying * packet buffer. Therefore, at load time, all checks on pointers @@ -6293,6 +6319,10 @@ enum bpf_adj_room_flags { BPF_F_ADJ_ROOM_ENCAP_L2_ETH = (1ULL << 6), BPF_F_ADJ_ROOM_DECAP_L3_IPV4 = (1ULL << 7), BPF_F_ADJ_ROOM_DECAP_L3_IPV6 = (1ULL << 8), + BPF_F_ADJ_ROOM_DECAP_L4_GRE = (1ULL << 9), + BPF_F_ADJ_ROOM_DECAP_L4_UDP = (1ULL << 10), + BPF_F_ADJ_ROOM_DECAP_IPXIP4 = (1ULL << 11), + BPF_F_ADJ_ROOM_DECAP_IPXIP6 = (1ULL << 12), }; enum { diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index f6c9dc856858..732b35cc08d1 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -3038,8 +3038,34 @@ union bpf_attr { * * * **BPF_F_ADJ_ROOM_DECAP_L3_IPV4**, * **BPF_F_ADJ_ROOM_DECAP_L3_IPV6**: - * Indicate the new IP header version after decapsulating the outer - * IP header. Used when the inner and outer IP versions are different. + * Indicate the new IP header version after decapsulating the + * outer IP header. Used when the inner and outer IP versions + * are different. These flags only trigger a protocol change + * without clearing any tunnel-specific GSO flags. + * + * * **BPF_F_ADJ_ROOM_DECAP_L4_GRE**: + * Clear GRE tunnel GSO flags (SKB_GSO_GRE and SKB_GSO_GRE_CSUM) + * when decapsulating a GRE tunnel. + * + * * **BPF_F_ADJ_ROOM_DECAP_L4_UDP**: + * Clear UDP tunnel GSO flags (SKB_GSO_UDP_TUNNEL and + * SKB_GSO_UDP_TUNNEL_CSUM) when decapsulating a UDP tunnel. + * + * * **BPF_F_ADJ_ROOM_DECAP_IPXIP4**: + * Clear IPIP/SIT tunnel GSO flag (SKB_GSO_IPXIP4) when decapsulating + * a tunnel with an outer IPv4 header (IPv4-in-IPv4 or IPv6-in-IPv4). + * + * * **BPF_F_ADJ_ROOM_DECAP_IPXIP6**: + * Clear IPv6 encapsulation tunnel GSO flag (SKB_GSO_IPXIP6) when + * decapsulating a tunnel with an outer IPv6 header (IPv6-in-IPv6 + * or IPv4-in-IPv6). + * + * When using the decapsulation flags above, the skb->encapsulation + * flag is automatically cleared if all tunnel-specific GSO flags + * (SKB_GSO_UDP_TUNNEL, SKB_GSO_UDP_TUNNEL_CSUM, SKB_GSO_GRE, + * SKB_GSO_GRE_CSUM, SKB_GSO_IPXIP4, SKB_GSO_IPXIP6) have been + * removed from the packet. This handles cases where all tunnel + * layers have been decapsulated. * * A call to this helper is susceptible to change the underlying * packet buffer. Therefore, at load time, all checks on pointers @@ -6293,6 +6319,10 @@ enum bpf_adj_room_flags { BPF_F_ADJ_ROOM_ENCAP_L2_ETH = (1ULL << 6), BPF_F_ADJ_ROOM_DECAP_L3_IPV4 = (1ULL << 7), BPF_F_ADJ_ROOM_DECAP_L3_IPV6 = (1ULL << 8), + BPF_F_ADJ_ROOM_DECAP_L4_GRE = (1ULL << 9), + BPF_F_ADJ_ROOM_DECAP_L4_UDP = (1ULL << 10), + BPF_F_ADJ_ROOM_DECAP_IPXIP4 = (1ULL << 11), + BPF_F_ADJ_ROOM_DECAP_IPXIP6 = (1ULL << 12), }; enum { -- cgit