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| author |   Martin KaFai Lau <kafai@fb.com> | 2016-12-07 15:53:11 -0800 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2016-12-08 14:25:13 -0500 |
| commit | 17bedab2723145d17b14084430743549e6943d03 (patch) | |
| tree | 6a1517e36c1be543f591b5ff7fcd7e816dcc906a /kernel/bpf | |
| parent | Merge branch 'lan7801-mac-only' (diff) | |
| download | linux-dev-17bedab2723145d17b14084430743549e6943d03.tar.xz linux-dev-17bedab2723145d17b14084430743549e6943d03.zip | |
bpf: xdp: Allow head adjustment in XDP prog
This patch allows XDP prog to extend/remove the packet
data at the head (like adding or removing header). It is
done by adding a new XDP helper bpf_xdp_adjust_head().
It also renames bpf_helper_changes_skb_data() to
bpf_helper_changes_pkt_data() to better reflect
that XDP prog does not work on skb.
This patch adds one "xdp_adjust_head" bit to bpf_prog for the
XDP-capable driver to check if the XDP prog requires
bpf_xdp_adjust_head() support. The driver can then decide
to error out during XDP_SETUP_PROG.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'kernel/bpf')
| -rw-r--r-- | kernel/bpf/core.c | 2 | ||||
| -rw-r--r-- | kernel/bpf/syscall.c | 2 | ||||
| -rw-r--r-- | kernel/bpf/verifier.c | 2 |
3 files changed, 4 insertions, 2 deletions
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index bdcc9f4ba767..83e0d153b0b4 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -1143,7 +1143,7 @@ struct bpf_prog * __weak bpf_int_jit_compile(struct bpf_prog *prog) return prog; } -bool __weak bpf_helper_changes_skb_data(void *func) +bool __weak bpf_helper_changes_pkt_data(void *func) { return false; } diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 88f609f1c0c3..4819ec9d95f6 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -579,6 +579,8 @@ static void fixup_bpf_calls(struct bpf_prog *prog) prog->dst_needed = 1; if (insn->imm == BPF_FUNC_get_prandom_u32) bpf_user_rnd_init_once(); + if (insn->imm == BPF_FUNC_xdp_adjust_head) + prog->xdp_adjust_head = 1; if (insn->imm == BPF_FUNC_tail_call) { /* mark bpf_tail_call as different opcode * to avoid conditional branch in diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 5b14f85f45c6..d28f9a3380a9 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -1216,7 +1216,7 @@ static int check_call(struct bpf_verifier_env *env, int func_id) return -EINVAL; } - changes_data = bpf_helper_changes_skb_data(fn->func); + changes_data = bpf_helper_changes_pkt_data(fn->func); memset(&meta, 0, sizeof(meta)); meta.pkt_access = fn->pkt_access; |