dccp: do not leak jiffies on the wire

BugLink: https://bugs.launchpad.net/bugs/1852110

[ Upstream commit 3d1e5039 ]

For some reason I missed the case of DCCP passive
flows in my previous patch.

Fixes: a904a069 ("inet: stop leaking jiffies on the wire")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Thiemo Nagel <tnagel@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Connor Kuehl <connor.kuehl@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

net/dccp/ipv4.c

@@ -417,7 +417,7 @@ struct sock *dccp_v4_request_recv_sock(const struct sock *sk,
 	RCU_INIT_POINTER(newinet->inet_opt, rcu_dereference(ireq->ireq_opt));
 	newinet->mc_index  = inet_iif(skb);
 	newinet->mc_ttl	   = ip_hdr(skb)->ttl;
-	newinet->inet_id   = jiffies;
+	newinet->inet_id   = prandom_u32();
 
 	if (dst == NULL && (dst = inet_csk_route_child_sock(sk, newsk, req)) == NULL)
 		goto put_and_exit;