From c041778c966c92c964033f1cdfee60a9f2b5e465 Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Wed, 29 Jun 2016 10:36:39 +0200 Subject: [PATCH] cfg80211: fix proto in ieee80211_data_to_8023 for frames without LLC header The PDU length of incoming LLC frames is set to the total skb payload size in __ieee80211_data_to_8023() of net/wireless/util.c which incorrectly includes the length of the IEEE 802.11 header. The resulting LLC frame header has a too large PDU length, causing the llc_fixup_skb() function of net/llc/llc_input.c to reject the incoming skb, effectively breaking STP. Solve the problem by properly substracting the IEEE 802.11 frame header size from the PDU length, allowing the LLC processor to pick up the incoming control messages. Special thanks to Gerry Rozema for tracking down the regression and proposing a suitable patch. Fixes: 2d1c304cb2d5 ("cfg80211: add function for 802.3 conversion with separate output buffer") Cc: stable@vger.kernel.org Reported-by: Gerry Rozema Signed-off-by: Felix Fietkau Signed-off-by: Johannes Berg --- net/wireless/util.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/wireless/util.c b/net/wireless/util.c index 4e809e978b7d..2443ee30ba5b 100644 --- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -509,7 +509,7 @@ static int __ieee80211_data_to_8023(struct sk_buff *skb, struct ethhdr *ehdr, * replace EtherType */ hdrlen += ETH_ALEN + 2; else - tmp.h_proto = htons(skb->len); + tmp.h_proto = htons(skb->len - hdrlen); pskb_pull(skb, hdrlen); -- 2.20.1