l2tp: Add ppp device name to L2TP ppp session data

When dumping L2TP PPP sessions using /proc/net/pppol2tp, get the
assigned PPP device name from PPP using ppp_dev_name().

Signed-off-by: James Chapman <jchapman@katalix.com>
Reviewed-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 0 deletions

diff --git a/net/l2tp/l2tp_ppp.c b/net/l2tp/l2tp_ppp.c
index baac072761aa..3ad290dd830a 100644
--- a/net/l2tp/l2tp_ppp.c
+++ b/net/l2tp/l2tp_ppp.c
@@ -1465,6 +1465,7 @@ static void pppol2tp_seq_session_show(struct seq_file *m, void *v)
         struct l2tp_session *session = v;
         struct l2tp_tunnel *tunnel = session->tunnel;
         struct pppol2tp_session *ps = l2tp_session_priv(session);
+        struct pppox_sock *po = pppox_sk(ps->sock);
         u32 ip = 0;
         u16 port = 0;
 
@@ -1499,6 +1500,9 @@ static void pppol2tp_seq_session_show(struct seq_file *m, void *v)
                    (unsigned long long)session->stats.rx_packets,
                    (unsigned long long)session->stats.rx_bytes,
                    (unsigned long long)session->stats.rx_errors);
+
+        if (po)
+                seq_printf(m, "   interface %s\n", ppp_dev_name(&po->chan));
 }
 
 static int pppol2tp_seq_show(struct seq_file *m, void *v)