From 07b0188adf7298bf80a9890d3e90f27e973623d3 Mon Sep 17 00:00:00 2001 From: Alexander Aring Date: Fri, 19 Feb 2016 09:59:11 +0100 Subject: mac802154: fix mac header length check I got report about that sometimes the WARN_ON occurs there which should never happen. I came to the conclusion that the mac header is there but inside the headroom of skb. The skb->len information doesn't contain the information about the headroom length and skb->len is lesser than two. We check now if the skb_mac_header pointer is set and the room between mac header pointer and tail pointer. Signed-off-by: Alexander Aring Signed-off-by: Marcel Holtmann --- include/net/mac802154.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'include/net/mac802154.h') diff --git a/include/net/mac802154.h b/include/net/mac802154.h index da574bbdc333..2e3cdd2048d2 100644 --- a/include/net/mac802154.h +++ b/include/net/mac802154.h @@ -247,8 +247,9 @@ struct ieee802154_ops { */ static inline __le16 ieee802154_get_fc_from_skb(const struct sk_buff *skb) { - /* return some invalid fc on failure */ - if (unlikely(skb->len < 2)) { + /* check if we can fc at skb_mac_header of sk buffer */ + if (unlikely(!skb_mac_header_was_set(skb) || + (skb_tail_pointer(skb) - skb_mac_header(skb)) < 2)) { WARN_ON(1); return cpu_to_le16(0); } -- cgit v1.2.3-59-g8ed1b