Re: [PATCH net v2] ipv6: remove null_entry before adding default route

On Mon, Jan 08, 2018 at 10:34:00AM -0800, Wei Wang wrote:

From: Wei Wang <redacted>

In the current code, when creating a new fib6 table, tb6_root.leaf gets
initialized to net->ipv6.ip6_null_entry.
If a default route is being added with rt->rt6i_metric = 0xffffffff,
fib6_add() will add this route after net->ipv6.ip6_null_entry. As
null_entry is shared, it could cause problem.

In order to fix it, set fn->leaf to NULL before calling
fib6_add_rt2node() when trying to add the first default route.
And reset fn->leaf to null_entry when adding fails or when deleting the
last default route.

Thanks for the fix!

Acked-by: Martin KaFai Lau <redacted>