3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Guillaume Nault <g.nault@xxxxxxxxxxxx> [ Upstream commit 8b82547e33e85fc24d4d172a93c796de1fefa81a ] The sendmsg() syscall handler for PPPoL2TP doesn't decrease the socket reference counter after successful transmissions. Any successful sendmsg() call from userspace will then increase the reference counter forever, thus preventing the kernel's session and tunnel data from being freed later on. The problem only happens when writing directly on L2TP sockets. PPP sockets attached to L2TP are unaffected as the PPP subsystem uses pppol2tp_xmit() which symmetrically increase/decrease reference counters. This patch adds the missing call to sock_put() before returning from pppol2tp_sendmsg(). 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 | 1 + 1 file changed, 1 insertion(+) --- a/net/l2tp/l2tp_ppp.c +++ b/net/l2tp/l2tp_ppp.c @@ -360,6 +360,7 @@ static int pppol2tp_sendmsg(struct kiocb l2tp_xmit_skb(session, skb, session->hdr_len); sock_put(ps->tunnel_sock); + sock_put(sk); return error; -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html