[PATCH 3.2 74/95] l2tp: don't mask errors in pppol2tp_getsockopt()

From: Ben Hutchings
Date: Sun Jul 16 2017 - 11:04:14 EST


3.2.91-rc1 review patch. If anyone has any objections, please let me know.

------------------

From: Guillaume Nault <g.nault@xxxxxxxxxxxx>

commit 321a52a39189d5e4af542f7dcdc07bba4545cf5d upstream.

pppol2tp_getsockopt() doesn't take into account the error code returned
by pppol2tp_tunnel_getsockopt() or pppol2tp_session_getsockopt(). If
error occurs there, pppol2tp_getsockopt() continues unconditionally and
reports erroneous values.

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: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
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
@@ -1509,8 +1509,13 @@ static int pppol2tp_getsockopt(struct so

err = pppol2tp_tunnel_getsockopt(sk, tunnel, optname, &val);
sock_put(ps->tunnel_sock);
- } else
+ if (err)
+ goto end_put_sess;
+ } else {
err = pppol2tp_session_getsockopt(sk, session, optname, &val);
+ if (err)
+ goto end_put_sess;
+ }

err = -EFAULT;
if (put_user(len, (int __user *) optlen))