From c05731d0c6bd9a625e27ea5c5157ebf1303229e0 Mon Sep 17 00:00:00 2001 From: Thadeu Lima de Souza Cascardo Date: Wed, 22 Sep 2021 08:56:56 -0300 Subject: [PATCH] Bluetooth: hci_ldisc: require CAP_NET_ADMIN to attach N_HCI ldisc Any unprivileged user can attach N_HCI ldisc and send packets coming from a virtual controller by using PTYs. Require initial namespace CAP_NET_ADMIN to do that. Signed-off-by: Thadeu Lima de Souza Cascardo Signed-off-by: Marcel Holtmann --- drivers/bluetooth/hci_ldisc.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c index 5ed2cfa7da1d..5e32e4d5367a 100644 --- a/drivers/bluetooth/hci_ldisc.c +++ b/drivers/bluetooth/hci_ldisc.c @@ -479,6 +479,9 @@ static int hci_uart_tty_open(struct tty_struct *tty) BT_DBG("tty %p", tty); + if (!capable(CAP_NET_ADMIN)) + return -EPERM; + /* Error if the tty has no write op instead of leaving an exploitable * hole */