From 3805a938a6c24284863732fd45cec5a04609a224 Mon Sep 17 00:00:00 2001 From: Eric Garver Date: Mon, 17 Oct 2016 16:30:12 -0400 Subject: [PATCH] flow_dissector: Check skb for VLAN only if skb specified. Fixes a panic when calling eth_get_headlen(). Noticed on i40e driver. Fixes: d5709f7ab776 ("flow_dissector: For stripped vlan, get vlan info from skb->vlan_tci") Signed-off-by: Eric Garver Reviewed-by: Jakub Sitnicki Acked-by: Amir Vadai Signed-off-by: David S. Miller --- net/core/flow_dissector.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index 1a7b80f73376..44e6ba9d3a6b 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -247,12 +247,10 @@ ipv6: case htons(ETH_P_8021Q): { const struct vlan_hdr *vlan; - if (skb_vlan_tag_present(skb)) + if (skb && skb_vlan_tag_present(skb)) proto = skb->protocol; - if (!skb_vlan_tag_present(skb) || - proto == cpu_to_be16(ETH_P_8021Q) || - proto == cpu_to_be16(ETH_P_8021AD)) { + if (eth_type_vlan(proto)) { struct vlan_hdr _vlan; vlan = __skb_header_pointer(skb, nhoff, sizeof(_vlan), -- 2.20.1