Bluetooth: SCO - Fix missing msg_namelen update in sco_sock_recvmsg()

[ Upstream commit c8c499175f7d295ef867335bceb9a76a2c3cdc38 ]

If the socket is in state BT_CONNECT2 and BT_SK_DEFER_SETUP is set in
the flags, sco_sock_recvmsg() returns early with 0 without updating the
possibly set msg_namelen member. This, in turn, leads to a 128 byte
kernel stack leak in net/socket.c.

Fix this by updating msg_namelen in this case. For all other cases it
will be handled in bt_sock_recvmsg().

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: Gustavo Padovan <gustavo@padovan.org>
Cc: Johan Hedberg <johan.hedberg@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c
index aaf1957bc4fea023e0be0d66fb96e64e359dfc54..cc16d1bccf54ae66ff448f275882454b3f66df42 100644 (file)
--- a/net/bluetooth/sco.c
+++ b/net/bluetooth/sco.c
@@ -667,6 +667,7 @@ static int sco_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
            test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags)) {
                hci_conn_accept(pi->conn->hcon, 0);
                sk->sk_state = BT_CONFIG;
+               msg->msg_namelen = 0;
 
                release_sock(sk);
                return 0;