bpf: add own ctx rewriter on ifindex for clsact progs

When fetching ifindex, we don't need to test dev for being NULL since
we're always guaranteed to have a valid dev for clsact programs. Thus,
avoid this test in fast path.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Daniel Borkmann 2016-09-09 02:45:30 +02:00 committed by David S. Miller
parent f035a51536
commit 374fb54eea

View File

@ -2634,10 +2634,10 @@ void bpf_warn_invalid_xdp_action(u32 act)
}
EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action);
static u32 bpf_net_convert_ctx_access(enum bpf_access_type type, int dst_reg,
int src_reg, int ctx_off,
struct bpf_insn *insn_buf,
struct bpf_prog *prog)
static u32 sk_filter_convert_ctx_access(enum bpf_access_type type, int dst_reg,
int src_reg, int ctx_off,
struct bpf_insn *insn_buf,
struct bpf_prog *prog)
{
struct bpf_insn *insn = insn_buf;
@ -2785,6 +2785,31 @@ static u32 bpf_net_convert_ctx_access(enum bpf_access_type type, int dst_reg,
return insn - insn_buf;
}
static u32 tc_cls_act_convert_ctx_access(enum bpf_access_type type, int dst_reg,
int src_reg, int ctx_off,
struct bpf_insn *insn_buf,
struct bpf_prog *prog)
{
struct bpf_insn *insn = insn_buf;
switch (ctx_off) {
case offsetof(struct __sk_buff, ifindex):
BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, ifindex) != 4);
*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
dst_reg, src_reg,
offsetof(struct sk_buff, dev));
*insn++ = BPF_LDX_MEM(BPF_W, dst_reg, dst_reg,
offsetof(struct net_device, ifindex));
break;
default:
return sk_filter_convert_ctx_access(type, dst_reg, src_reg,
ctx_off, insn_buf, prog);
}
return insn - insn_buf;
}
static u32 xdp_convert_ctx_access(enum bpf_access_type type, int dst_reg,
int src_reg, int ctx_off,
struct bpf_insn *insn_buf,
@ -2811,13 +2836,13 @@ static u32 xdp_convert_ctx_access(enum bpf_access_type type, int dst_reg,
static const struct bpf_verifier_ops sk_filter_ops = {
.get_func_proto = sk_filter_func_proto,
.is_valid_access = sk_filter_is_valid_access,
.convert_ctx_access = bpf_net_convert_ctx_access,
.convert_ctx_access = sk_filter_convert_ctx_access,
};
static const struct bpf_verifier_ops tc_cls_act_ops = {
.get_func_proto = tc_cls_act_func_proto,
.is_valid_access = tc_cls_act_is_valid_access,
.convert_ctx_access = bpf_net_convert_ctx_access,
.convert_ctx_access = tc_cls_act_convert_ctx_access,
};
static const struct bpf_verifier_ops xdp_ops = {