29.12.2015 14:58, Sowmini Varadhan пишет: > On (12/29/15 13:54), Stas Sergeev wrote: >> >> ip route get 91.189.89.238 >> 91.189.89.238 via 192.168.0.1 dev eth0 src 192.168.10.202 >> cache <redirected> > : >> Now, 192.168.0.1 is also a valid gateway, but it is outside >> of the network mask for the eth0 interface: > : >> So my question is: why does linux allow an invalid redirect >> entries? Is it a problem with my setup, or some kernel bug, >> or some router setup problem? Where should I look into, to >> nail this down? > > Seems like the problem is in the router that is sending > the bad redirect. You would have to check into the configuration > and/or implementation of the router- it should not be sending > back a redirect in the above case (different netmasks) even > if the ingress and egress physical interfaces are the same. Router on 192.168.8.1 is just a PC with ubuntu, w/o any special software. I'd be very surprised if it does so. As I understand, linux would accept such ICMP redirect only from the router, or could someone else also send them?
But what worries me more, is the question: Should the linux kernel really silently accept those, breaking the routing in a completely unexpected ways? Isn't it a bug? The sanity check against netmask looks trivial, so why it is not there? -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html