Hi Andreas, On Tue, Jan 24, 2017 at 06:24:02PM +0100, Andreas Schultz wrote: > enable userspace to send error replies for invalid tunnels > > Signed-off-by: Andreas Schultz <aschu...@tpip.net> > --- > drivers/net/gtp.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/drivers/net/gtp.c b/drivers/net/gtp.c > index 912721e..c607333 100644 > --- a/drivers/net/gtp.c > +++ b/drivers/net/gtp.c > @@ -198,12 +198,12 @@ static int gtp0_udp_encap_recv(struct gtp_dev *gtp, > struct sk_buff *skb, > pctx = gtp0_pdp_find(gtp, be64_to_cpu(gtp0->tid)); > if (!pctx) { > netdev_dbg(gtp->dev, "No PDP ctx to decap skb=%p\n", skb); > - return -1; > + return 1; > } > > if (!gtp_check_src_ms(skb, pctx, hdrlen)) { > netdev_dbg(gtp->dev, "No PDP ctx for this MS\n"); > - return -1; > + return 1;
So userspace gets the packet that we cannot forward. I guess your userspace codebase performs this sanity checks again so you can send the appropriate error reply? > } > > /* Get rid of the GTP + UDP headers. */ > @@ -247,12 +247,12 @@ static int gtp1u_udp_encap_recv(struct gtp_dev *gtp, > struct sk_buff *skb, > pctx = gtp1_pdp_find(gtp, ntohl(gtp1->tid)); > if (!pctx) { > netdev_dbg(gtp->dev, "No PDP ctx to decap skb=%p\n", skb); > - return -1; > + return 1; > } > > if (!gtp_check_src_ms(skb, pctx, hdrlen)) { > netdev_dbg(gtp->dev, "No PDP ctx for this MS\n"); > - return -1; > + return 1; > } > > /* Get rid of the GTP + UDP headers. */ > -- > 2.10.2 >