PPC: bpf_jit_comp: add SKF_AD_HATYPE instruction

Add BPF extension SKF_AD_HATYPE to ppc JIT to check
the hw type of the interface

Before:
[   57.723666] test_bpf: #20 LD_HATYPE
[   57.723675] BPF filter opcode 0020 (@0) unsupported
[   57.724168] 48 48 PASS

After:
[  103.053184] test_bpf: #20 LD_HATYPE 7 6 PASS

CC: Alexei Starovoitov<alexei.starovoitov@gmail.com>
CC: Daniel Borkmann<dborkman@redhat.com>
CC: Philippe Bergheaud<felix@linux.vnet.ibm.com>
Signed-off-by: Denis Kirjanov <kda@linux-powerpc.org>
v2: address Alexei's comments
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
index d110e28..d3fa80d 100644 (file)
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c
@@ -361,6 +361,11 @@ static int bpf_jit_build_body(struct bpf_prog *fp, u32 *image,
                                                            protocol));
                        break;
                case BPF_ANC | SKF_AD_IFINDEX:
+               case BPF_ANC | SKF_AD_HATYPE:
+                       BUILD_BUG_ON(FIELD_SIZEOF(struct net_device,
+                                               ifindex) != 4);
+                       BUILD_BUG_ON(FIELD_SIZEOF(struct net_device,
+                                               type) != 2);
                        PPC_LD_OFFS(r_scratch1, r_skb, offsetof(struct sk_buff,
                                                                dev));
                        PPC_CMPDI(r_scratch1, 0);
@@ -368,14 +373,18 @@ static int bpf_jit_build_body(struct bpf_prog *fp, u32 *image,
                                PPC_BCC(COND_EQ, addrs[ctx->pc_ret0]);
                        } else {
                                /* Exit, returning 0; first pass hits here. */
-                               PPC_BCC_SHORT(COND_NE, (ctx->idx*4)+12);
+                               PPC_BCC_SHORT(COND_NE, ctx->idx * 4 + 12);
                                PPC_LI(r_ret, 0);
                                PPC_JMP(exit_addr);
                        }
-                       BUILD_BUG_ON(FIELD_SIZEOF(struct net_device,
-                                                 ifindex) != 4);
-                       PPC_LWZ_OFFS(r_A, r_scratch1,
+                       if (code == (BPF_ANC | SKF_AD_IFINDEX)) {
+                               PPC_LWZ_OFFS(r_A, r_scratch1,
                                     offsetof(struct net_device, ifindex));
+                       } else {
+                               PPC_LHZ_OFFS(r_A, r_scratch1,
+                                    offsetof(struct net_device, type));
+                       }
+
                        break;
                case BPF_ANC | SKF_AD_MARK:
                        BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, mark) != 4);