Bluetooth: Check the tx_window size on setsockopt

We have to check if the proposed tx_window value is not greater that
maximum value supported.

Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Reviewed-by: João Paulo Rechi Vita <jprvita@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

1 files changed, 5 insertions, 0 deletions

diff --git a/net/bluetooth/l2cap.c b/net/bluetooth/l2cap.c
index f0441b0b0335..6094870d5d2a 100644
--- a/net/bluetooth/l2cap.c
+++ b/net/bluetooth/l2cap.c
@@ -1912,6 +1912,11 @@ static int l2cap_sock_setsockopt_old(struct socket *sock, int optname, char __us
                         break;
                 }
 
+                if (opts.txwin_size > L2CAP_DEFAULT_TX_WINDOW) {
+                        err = -EINVAL;
+                        break;
+                }
+
                 l2cap_pi(sk)->mode = opts.mode;
                 switch (l2cap_pi(sk)->mode) {
                 case L2CAP_MODE_BASIC: