If VLAN_TAG_PRESENT is not zero, then return 1 as expected by
classic BPF. Otherwise return 0.
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
Cc: Daniel Borkmann <dborkman@xxxxxxxxxx>
Cc: Alexei Starovoitov <ast@xxxxxxxxxxxx>
Cc: netdev@xxxxxxxxxxxxxxx
Signed-off-by: Markos Chandras <markos.chandras@xxxxxxxxxx>
---
arch/mips/net/bpf_jit.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/arch/mips/net/bpf_jit.c b/arch/mips/net/bpf_jit.c
index a4d1b76e7373..d852bb6d3fe3 100644
--- a/arch/mips/net/bpf_jit.c
+++ b/arch/mips/net/bpf_jit.c
@@ -1316,10 +1316,13 @@ jmp_cmp:
vlan_tci) != 2);
off = offsetof(struct sk_buff, vlan_tci);
emit_half_load(r_s0, r_skb, off, ctx);
- if (code == (BPF_ANC | SKF_AD_VLAN_TAG))
+ if (code == (BPF_ANC | SKF_AD_VLAN_TAG)) {
emit_andi(r_A, r_s0, (u16)~VLAN_TAG_PRESENT, ctx);
- else
+ } else {
emit_andi(r_A, r_s0, VLAN_TAG_PRESENT, ctx);
+ /* return 1 if present */
+ emit_sltu(r_A, r_zero, r_A, ctx);
+ }
break;
case BPF_ANC | SKF_AD_PKTTYPE:
ctx->flags |= SEEN_SKB;
--
2.0.0
