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

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().

Cc: Marcel Holtmann <[email protected]>
Cc: Gustavo Padovan <[email protected]>
Cc: Johan Hedberg <[email protected]>
Signed-off-by: Mathias Krause <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c
index fad0302bdb325e5df700edf4fe323c6226216599..fb6192c9812e81bcac3d8dea31f60095aa40ffda 100644 (file)
--- a/net/bluetooth/sco.c
+++ b/net/bluetooth/sco.c
@@ -665,6 +665,7 @@ 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;