From d928be81b44dc3cad75d7a9f9fcbe99725dc7e56 Mon Sep 17 00:00:00 2001 From: Harald Welte Date: Thu, 15 Dec 2016 22:35:53 +0100 Subject: [PATCH] gtp: Fix initialization of Flags octet in GTPv1 header When generating a GTPv1 header in gtp1_push_header(), initialize the 'reserved' bit to zero. All 3GPP specifications for GTPv1 from Release 99 through Release 13 agree that a transmitter shall set this bit to zero, see e.g. Note 0 of Figure 2 in Section 6 of 3GPP TS 29.060 v13.5.0 Release 13, available from http://www.etsi.org/deliver/etsi_ts/129000_129099/129060/13.05.00_60/ts_129060v130500p.pdf Signed-off-by: Harald Welte Signed-off-by: Pablo Neira Ayuso Signed-off-by: David S. Miller --- drivers/net/gtp.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/gtp.c b/drivers/net/gtp.c index 6031d49..8b6810b 100644 --- a/drivers/net/gtp.c +++ b/drivers/net/gtp.c @@ -423,11 +423,11 @@ static inline void gtp1_push_header(struct sk_buff *skb, struct pdp_ctx *pctx) /* Bits 8 7 6 5 4 3 2 1 * +--+--+--+--+--+--+--+--+ - * |version |PT| 1| E| S|PN| + * |version |PT| 0| E| S|PN| * +--+--+--+--+--+--+--+--+ * 0 0 1 1 1 0 0 0 */ - gtp1->flags = 0x38; /* v1, GTP-non-prime. */ + gtp1->flags = 0x30; /* v1, GTP-non-prime. */ gtp1->type = GTP_TPDU; gtp1->length = htons(payload_len); gtp1->tid = htonl(pctx->u.v1.o_tei); -- 2.7.4