| Message ID | 20130808224440.GJ14001@order.stressinduktion.org |
|---|---|
| State | RFC, archived |
| Delegated to: | David Miller |
| Headers | show |
On Fri, 2013-08-09 at 00:44 +0200, Hannes Frederic Sowa wrote: > On Thu, Aug 01, 2013 at 12:05:22PM +0200, Steffen Klassert wrote: > > On Thu, Aug 01, 2013 at 10:11:50AM +0200, Hannes Frederic Sowa wrote: > > > > > > If you have not yet done so, I would try to find a solution over the weekend. > > > > > > > I have not yet done so, please go ahead. > > Ok, this patch should do the trick. In xfrm6 error path we now generate > a plain icmpv6 packet back to us in this specific case vi0oss reported. I > wonder if we should suppress these. > > Btw. is the memset(IPCB, 0) actually needed in the ipv4 output path? > > [PATCH RFC] net: orphan socket when skb traverses tunnel interface > > When a local generated packet traverses a tunnel the socket has to be > orphaned from the skb. Otherwise lower layer, like xfrm, try to report > errors directly to this socket. If, because of a transitioning tunnel, > the address family changes we deliver an invalid error or panic in the > error reporting functions. > > Also add a call to secpath_reset() in the ipv6 tunnel xmit path. It > seems like it was just forgotten. > > Reported-by: <vi0oss@gmail.com> > Cc: Steffen Klassert <steffen.klassert@secunet.com> > Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> > --- Doing so breaks flow control. A single socket can flood and fill the Qdisc, even a friendly one like a local TCP flow (see TCP Small Queues) Can't we make the error reporting more robust instead ? -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, Aug 08, 2013 at 03:57:57PM -0700, Eric Dumazet wrote: > On Fri, 2013-08-09 at 00:44 +0200, Hannes Frederic Sowa wrote: > > On Thu, Aug 01, 2013 at 12:05:22PM +0200, Steffen Klassert wrote: > > > On Thu, Aug 01, 2013 at 10:11:50AM +0200, Hannes Frederic Sowa wrote: > > > > > > > > If you have not yet done so, I would try to find a solution over the weekend. > > > > > > > > > > I have not yet done so, please go ahead. > > > > Ok, this patch should do the trick. In xfrm6 error path we now generate > > a plain icmpv6 packet back to us in this specific case vi0oss reported. I > > wonder if we should suppress these. > > > > Btw. is the memset(IPCB, 0) actually needed in the ipv4 output path? > > > > [PATCH RFC] net: orphan socket when skb traverses tunnel interface > > > > When a local generated packet traverses a tunnel the socket has to be > > orphaned from the skb. Otherwise lower layer, like xfrm, try to report > > errors directly to this socket. If, because of a transitioning tunnel, > > the address family changes we deliver an invalid error or panic in the > > error reporting functions. > > > > Also add a call to secpath_reset() in the ipv6 tunnel xmit path. It > > seems like it was just forgotten. > > > > Reported-by: <vi0oss@gmail.com> > > Cc: Steffen Klassert <steffen.klassert@secunet.com> > > Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> > > --- > > Doing so breaks flow control. > > A single socket can flood and fill the Qdisc, even a friendly one like a > local TCP flow (see TCP Small Queues) > > Can't we make the error reporting more robust instead ? Hm, I thought so. My other patch (some mails above in this thread) checks for a switch in address family and does prohibit the panic, but generates wrong error reports back to the socket if the address family does not switch (which maybe get ignored). I will check if the skb->encapsulated bit could help. Actually I don't know what the correct behaviour for error reporting should be in the end, maybe: dispatch packet back to tunnel interface, let tunnel interface decapsulate the inner packet and use this inner header to inform the original socket about the error. Thanks, Hannes -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/include/net/ip6_tunnel.h b/include/net/ip6_tunnel.h index 4da5de1..92770de 100644 --- a/include/net/ip6_tunnel.h +++ b/include/net/ip6_tunnel.h @@ -6,6 +6,8 @@ #include <linux/if_tunnel.h> #include <linux/ip6_tunnel.h> +#include <net/xfrm.h> + #define IP6TUNNEL_ERR_TIMEO (30*HZ) /* capable of sending packets */ @@ -74,7 +76,10 @@ static inline void ip6tunnel_xmit(struct sk_buff *skb, struct net_device *dev) struct net_device_stats *stats = &dev->stats; int pkt_len, err; + skb_orphan(skb); nf_reset(skb); + secpath_reset(skb); + skb->rxhash = 0; pkt_len = skb->len; err = ip6_local_out(skb); diff --git a/net/ipv4/ip_tunnel_core.c b/net/ipv4/ip_tunnel_core.c index 7167b08..8a1a378 100644 --- a/net/ipv4/ip_tunnel_core.c +++ b/net/ipv4/ip_tunnel_core.c @@ -55,6 +55,7 @@ int iptunnel_xmit(struct net *net, struct rtable *rt, struct iphdr *iph; int err; + skb_orphan(skb); nf_reset(skb); secpath_reset(skb); skb->rxhash = 0;