Netlink: Handle alien routes with unsorted nexthops

Nest requires that nexthops are sorted, the kernel protocol have to
ensure that for alien routes.

1 files changed, 4 insertions, 0 deletions

diff --git a/sysdep/linux/netlink.c b/sysdep/linux/netlink.c
index 5a0b4d0c..6e3fe488 100644
--- a/sysdep/linux/netlink.c
+++ b/sysdep/linux/netlink.c
@@ -725,6 +725,10 @@ nl_parse_multipath(struct nl_parse_state *s, struct krt_proto *p, struct rtattr
       nh = RTNH_NEXT(nh);
     }
 
+  /* Ensure nexthops are sorted to satisfy nest invariant */
+  if (!nexthop_is_sorted(first))
+    first = nexthop_sort(first);
+
   return first;
 }