Index: sys/netinet/in_proto.c
===================================================================
RCS file: /mount/openbsd/cvs/src/sys/netinet/in_proto.c,v
diff -u -p -u -p -r1.106 in_proto.c
--- sys/netinet/in_proto.c	13 Jul 2024 12:00:11 -0000	1.106
+++ sys/netinet/in_proto.c	22 Jul 2024 06:48:59 -0000
@@ -185,7 +185,7 @@ const struct protosw inetsw[] = {
   .pr_type	= SOCK_DGRAM,
   .pr_domain	= &inetdomain,
   .pr_protocol	= IPPROTO_UDP,
-  .pr_flags	= PR_ATOMIC|PR_ADDR|PR_SPLICE|PR_MPSOCKET,
+  .pr_flags	= PR_ATOMIC|PR_ADDR|PR_SPLICE|PR_MPINPUT|PR_MPSOCKET,
   .pr_input	= udp_input,
   .pr_ctlinput	= udp_ctlinput,
   .pr_ctloutput	= ip_ctloutput,
Index: sys/netinet6/in6_proto.c
===================================================================
RCS file: /mount/openbsd/cvs/src/sys/netinet6/in6_proto.c,v
diff -u -p -u -p -r1.116 in6_proto.c
--- sys/netinet6/in6_proto.c	19 Jul 2024 16:58:32 -0000	1.116
+++ sys/netinet6/in6_proto.c	22 Jul 2024 06:48:59 -0000
@@ -136,7 +136,7 @@ const struct protosw inet6sw[] = {
   .pr_type	= SOCK_DGRAM,
   .pr_domain	= &inet6domain,
   .pr_protocol	= IPPROTO_UDP,
-  .pr_flags	= PR_ATOMIC|PR_ADDR|PR_SPLICE|PR_MPSOCKET,
+  .pr_flags	= PR_ATOMIC|PR_ADDR|PR_SPLICE|PR_MPINPUT|PR_MPSOCKET,
   .pr_input	= udp_input,
   .pr_ctlinput	= udp6_ctlinput,
   .pr_ctloutput	= ip6_ctloutput,