powerpc: bpf: Use correct mask while accessing the VLAN tag

To get a full tag (and not just a VID) we should access the TCI
except the VLAN_TAG_PRESENT field (which means that 802.1q header
is present). Also ensure that the VLAN_TAG_PRESENT stay on its place

Signed-off-by: Denis Kirjanov <kda@linux-powerpc.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Denis Kirjanov 2014-06-25 21:34:56 +04:00 committed by David S. Miller
parent e940f5d6ba
commit 3fc60aa097
1 changed files with 3 additions and 1 deletions

View File

@ -390,10 +390,12 @@ static int bpf_jit_build_body(struct sk_filter *fp, u32 *image,
case BPF_ANC | SKF_AD_VLAN_TAG:
case BPF_ANC | SKF_AD_VLAN_TAG_PRESENT:
BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_tci) != 2);
BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000);
PPC_LHZ_OFFS(r_A, r_skb, offsetof(struct sk_buff,
vlan_tci));
if (code == (BPF_ANC | SKF_AD_VLAN_TAG))
PPC_ANDI(r_A, r_A, VLAN_VID_MASK);
PPC_ANDI(r_A, r_A, ~VLAN_TAG_PRESENT);
else
PPC_ANDI(r_A, r_A, VLAN_TAG_PRESENT);
break;