diff mbox

[v2,1/2] powerpc: bpf: Use correct mask while accessing the VLAN tag

Message ID 1403717697-3911-1-git-send-email-kda@linux-powerpc.org (mailing list archive)
State Not Applicable
Headers show

Commit Message

Denis Kirjanov June 25, 2014, 5:34 p.m. UTC 
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>
---
 arch/powerpc/net/bpf_jit_comp.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

Comments

David Miller June 27, 2014, 11:14 p.m. UTC | #1 
From: Denis Kirjanov <kda@linux-powerpc.org>
Date: Wed, 25 Jun 2014 21:34:56 +0400

> 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>

Applied.
diff mbox

Patch

diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
index 6dcdade..892167b 100644
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c
@@ -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;