diff -drupN a/net/sctp/socket.c b/net/sctp/socket.c
--- a/net/sctp/socket.c	2018-08-06 17:23:04.000000000 +0300
+++ b/net/sctp/socket.c	2022-06-12 05:28:14.000000000 +0300
@@ -4785,6 +4785,10 @@ int sctp_do_peeloff(struct sock *sk, sct
 	if (!net_eq(current->nsproxy->net_ns, sock_net(sk)))
 		return -EINVAL;
 
+	/* Do not peel off from one netns to another one. */
+	if (!net_eq(current->nsproxy->net_ns, sock_net(sk)))
+		return -EINVAL;
+
 	if (!asoc)
 		return -EINVAL;