[PATCH net] Revert "ipv6: preserve insertion order for same-scope addresses"

[Fernando Fernandez Mancera <fmancera@suse.de>]

Chris Adams reported that preserving insertion order for same-scope
addresses is causing SSH connections to be dropped after stopping a VM
while running NetworkManager.

NetworkManager is caching the networking information from the system and
later operating with it. It relies on the order of IPv6 addresses to
configure routes for outgoing traffic. Revert to the previous ordering.

This reverts commit cb3de96eea66f5e4a580086c6a1be46e765f97f4.

Fixes: cb3de96eea66 ("ipv6: preserve insertion order for same-scope addresses")
Reported-by: Chris Adams <linux@cmadams.net>
Closes: https://lore.kernel.org/netdev/20260521135310.GC977@cmadams.net/
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
---
 net/ipv6/addrconf.c                  | 2 +-
 tools/testing/selftests/net/ioam6.sh | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 5476b6536eb7..bb84a78b80f6 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -1013,7 +1013,7 @@ ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
 	list_for_each(p, &idev->addr_list) {
 		struct inet6_ifaddr *ifa
 			= list_entry(p, struct inet6_ifaddr, if_list);
-		if (ifp_scope > ipv6_addr_src_scope(&ifa->addr))
+		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
 			break;
 	}
 
diff --git a/tools/testing/selftests/net/ioam6.sh b/tools/testing/selftests/net/ioam6.sh
index b2b99889942f..845c26dd01a9 100755
--- a/tools/testing/selftests/net/ioam6.sh
+++ b/tools/testing/selftests/net/ioam6.sh
@@ -273,8 +273,8 @@ setup()
   ip -netns $ioam_node_beta link set ioam-veth-betaR name veth1 &>/dev/null
   ip -netns $ioam_node_gamma link set ioam-veth-gamma name veth0 &>/dev/null
 
-  ip -netns $ioam_node_alpha addr add 2001:db8:1::2/64 dev veth0 &>/dev/null
   ip -netns $ioam_node_alpha addr add 2001:db8:1::50/64 dev veth0 &>/dev/null
+  ip -netns $ioam_node_alpha addr add 2001:db8:1::2/64 dev veth0 &>/dev/null
   ip -netns $ioam_node_alpha link set veth0 up &>/dev/null
   ip -netns $ioam_node_alpha link set lo up &>/dev/null
   ip -netns $ioam_node_alpha route add 2001:db8:2::/64 \
-- 
2.54.0