Merge: ipv4: Don't reset ->flowi4_scope in ip_rt_fix_tos().

MR: https://gitlab.com/redhat/centos-stream/src/kernel/centos-stream-9/-/merge_requests/5284

JIRA: https://issues.redhat.com/browse/RHEL-59754

RHEL-57748 backported `ec20b2830093 ("ipv4: Set scope explicitly in ip_route_output().")`, which will set `ip_route_output` tos to 0. This breaks bonding arp monitoring as later in `ip_rt_fix_tos` the scope is reset to RT_SCOPE_UNIVERSE since `tos` is 0. The backported patch 16a2826 ("ipv4: Don't reset ->flowi4_scope in ip_rt_fix_tos().") fixed this issue as the scope will not set to RT_SCOPE_UNIVERSE.

Signed-off-by: Hangbin Liu <haliu@redhat.com>

Approved-by: Guillaume Nault <gnault@redhat.com>
Approved-by: Florian Westphal <fwestpha@redhat.com>
Approved-by: Ivan Vecera <ivecera@redhat.com>
Approved-by: CKI KWF Bot <cki-ci-bot+kwf-gitlab-com@redhat.com>

Merged-by: Rado Vrbovsky <rvrbovsk@redhat.com>

Author: emmil

net/ipv4/route.c

@@ -512,8 +512,8 @@ static void ip_rt_fix_tos(struct flowi4 *fl4)
 	__u8 tos = RT_FL_TOS(fl4);
 
 	fl4->flowi4_tos = tos & IPTOS_RT_MASK;
-	fl4->flowi4_scope = tos & RTO_ONLINK ?
-			    RT_SCOPE_LINK : RT_SCOPE_UNIVERSE;
+	if (tos & RTO_ONLINK)
+		fl4->flowi4_scope = RT_SCOPE_LINK;
 }
 
 static void __build_flow_key(const struct net *net, struct flowi4 *fl4,