On Mon, Oct 17, 2016 at 08:30 PM GMT, Eric Garver wrote: > 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 <e...@erig.me> > --- > 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 @@ bool __skb_flow_dissect(const struct sk_buff *skb, > 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; >
I was a bit confused that we check skb for VLAN tag again later in the same block but this time without a NULL check. However, this only happens when we get called from skb_flow_dissect() or skb_flow_dissect_flow_keys() variants, which take an skb and pass it to us. Feel free to add: Reviewed-by: Jakub Sitnicki <j...@redhat.com>