[PATCH 4.4 05/29] l2tp: Correctly return -EBADF from pppol2tp_getname.

From: Greg Kroah-Hartman
Date: Sat Apr 11 2020 - 08:29:29 EST


From: phil.turnbull@xxxxxxxxxx <phil.turnbull@xxxxxxxxxx>

commit 4ac36a4adaf80013a60013d6f829f5863d5d0e05 upstream.

If 'tunnel' is NULL we should return -EBADF but the 'end_put_sess' path
unconditionally sets 'error' back to zero. Rework the error path so it
more closely matches pppol2tp_sendmsg.

Fixes: fd558d186df2 ("l2tp: Split pppol2tp patch into separate l2tp and ppp parts")
Signed-off-by: Phil Turnbull <phil.turnbull@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
net/l2tp/l2tp_ppp.c | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)

--- a/net/l2tp/l2tp_ppp.c
+++ b/net/l2tp/l2tp_ppp.c
@@ -889,10 +889,8 @@ static int pppol2tp_getname(struct socke

pls = l2tp_session_priv(session);
tunnel = l2tp_sock_to_tunnel(pls->tunnel_sock);
- if (tunnel == NULL) {
- error = -EBADF;
+ if (tunnel == NULL)
goto end_put_sess;
- }

inet = inet_sk(tunnel->sock);
if ((tunnel->version == 2) && (tunnel->sock->sk_family == AF_INET)) {
@@ -970,12 +968,11 @@ static int pppol2tp_getname(struct socke
}

*usockaddr_len = len;
+ error = 0;

sock_put(pls->tunnel_sock);
end_put_sess:
sock_put(sk);
- error = 0;
-
end:
return error;
}