From 57b68ec2a7be9a7e9f8999850f8ee5baa49023e4 Mon Sep 17 00:00:00 2001 From: Colin Ian King Date: Fri, 13 Jan 2017 18:48:20 +0000 Subject: [PATCH] flow dissector: check if arp_eth is null rather than arp arp is being checked instead of arp_eth to see if the call to __skb_header_pointer failed. Fix this by checking arp_eth is null instead of arp. Also fix to use length hlen rather than hlen - sizeof(_arp); thanks to Eric Dumazet for spotting this latter issue. CoverityScan CID#1396428 ("Logically dead code") on 2nd arp comparison (which should be arp_eth instead). Fixes: commit 55733350e5e8b70c5 ("flow disector: ARP support") Signed-off-by: Colin Ian King Acked-by: Eric Dumazet Signed-off-by: David S. Miller --- net/core/flow_dissector.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index e3dffc7a4785..c35aae13c8d2 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -407,9 +407,9 @@ mpls: arp_eth = __skb_header_pointer(skb, nhoff + sizeof(_arp), sizeof(_arp_eth), data, - hlen - sizeof(_arp), + hlen, &_arp_eth); - if (!arp) + if (!arp_eth) goto out_bad; if (dissector_uses_key(flow_dissector,