From 8357db75267554aa83a1bd5324124e3cf38c13d0 Mon Sep 17 00:00:00 2001 From: Shmulik Ladkani Date: Fri, 21 Oct 2016 00:18:08 +0300 Subject: [PATCH] net/sched: em_meta: Fix 'meta vlan' to correctly recognize zero VID frames commit d65f2fa680d6f91438461df54c83a331b3a631c9 upstream. META_COLLECTOR int_vlan_tag() assumes that if the accel tag (vlan_tci) is zero, then no vlan accel tag is present. This is incorrect for zero VID vlan accel packets, making the following match fail: tc filter add ... basic match 'meta(vlan mask 0xfff eq 0)' ... Apparently 'int_vlan_tag' was implemented prior VLAN_TAG_PRESENT was introduced in 05423b2 "vlan: allow null VLAN ID to be used" (and at time introduced, the 'vlan_tx_tag_get' call in em_meta was not adapted). Fix, testing skb_vlan_tag_present instead of testing skb_vlan_tag_get's value. Fixes: 05423b2413 ("vlan: allow null VLAN ID to be used") Fixes: 1a31f2042e ("netsched: Allow meta match on vlan tag on receive") Signed-off-by: Shmulik Ladkani Cc: Eric Dumazet Cc: Stephen Hemminger Signed-off-by: David S. Miller [bwh: Backported to 3.2: s/skb_vlan_tag/vlan_tx_tag/] Signed-off-by: Ben Hutchings --- net/sched/em_meta.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/net/sched/em_meta.c b/net/sched/em_meta.c index 1363bf14e61b..892f66ac7a89 100644 --- a/net/sched/em_meta.c +++ b/net/sched/em_meta.c @@ -176,11 +176,12 @@ META_COLLECTOR(int_vlan_tag) { unsigned short tag; - tag = vlan_tx_tag_get(skb); - if (!tag && __vlan_get_tag(skb, &tag)) - *err = -1; - else + if (vlan_tx_tag_present(skb)) + dst->value = vlan_tx_tag_get(skb); + else if (!__vlan_get_tag(skb, &tag)) dst->value = tag; + else + *err = -1; } -- 2.39.2