4.13-stable review patch. If anyone has any objections, please let me know. ------------------ From: Guillaume Nault <g.nault@xxxxxxxxxxxx> [ Upstream commit f9e56baf03f9d36043a78f16e3e8b2cfd211e09e ] Use l2tp_tunnel_get() in pppol2tp_connect() to ensure the tunnel isn't going to disappear while processing the rest of the function. Fixes: fd558d186df2 ("l2tp: Split pppol2tp patch into separate l2tp and ppp parts") Signed-off-by: Guillaume Nault <g.nault@xxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/l2tp/l2tp_ppp.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/net/l2tp/l2tp_ppp.c +++ b/net/l2tp/l2tp_ppp.c @@ -584,6 +584,7 @@ static int pppol2tp_connect(struct socke u32 tunnel_id, peer_tunnel_id; u32 session_id, peer_session_id; bool drop_refcnt = false; + bool drop_tunnel = false; int ver = 2; int fd; @@ -652,7 +653,9 @@ static int pppol2tp_connect(struct socke if (tunnel_id == 0) goto end; - tunnel = l2tp_tunnel_find(sock_net(sk), tunnel_id); + tunnel = l2tp_tunnel_get(sock_net(sk), tunnel_id); + if (tunnel) + drop_tunnel = true; /* Special case: create tunnel context if session_id and * peer_session_id is 0. Otherwise look up tunnel using supplied @@ -781,6 +784,8 @@ out_no_ppp: end: if (drop_refcnt) l2tp_session_dec_refcount(session); + if (drop_tunnel) + l2tp_tunnel_dec_refcount(tunnel); release_sock(sk); return error;