Certain ttys operations (pty_unix98_ops) lack tiocmget() and tiocmset()
functions which are called by the certain HCI UART protocols (hci_ath,
hci_bcm, hci_intel, hci_mrvl, hci_qca) via hci_uart_set_flow_control()
or directly. This leads to an execution at NULL and can be triggered by
an unprivileged user. Fix this by adding a helper function and a check
for the missing tty operations in the protocols code.
This fixes CVE-2019-10207. The Fixes: lines list commits where calls to
tiocm[gs]et() or hci_uart_set_flow_control() were added to the HCI UART
protocols.
Link: https://syzkaller.appspot.com/bug?id=1b42faa2848963564a5b1b7f8c837ea7b55ffa50
Reported-by: syzbot+79337b501d6aa974d0f6@syzkaller.appspotmail.com
Cc: stable@vger.kernel.org # v2.6.36+
Fixes: b3190df62861 ("Bluetooth: Support for Atheros AR300x serial chip")
Fixes: 118612fb9165 ("Bluetooth: hci_bcm: Add suspend/resume PM functions")
Fixes: ff2895592f0f ("Bluetooth: hci_intel: Add Intel baudrate configuration support")
Fixes: 162f812f23ba ("Bluetooth: hci_uart: Add Marvell support")
Fixes: fa9ad876b8e0 ("Bluetooth: hci_qca: Add support for Qualcomm Bluetooth chip wcn3990")
Signed-off-by: Vladis Dronov <vdronov@redhat.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Reviewed-by: Yu-Chen, Cho <acho@suse.com>
Tested-by: Yu-Chen, Cho <acho@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
BT_DBG("hu %p", hu);
+ if (!hci_uart_has_flow_control(hu))
+ return -EOPNOTSUPP;
+
ath = kzalloc(sizeof(*ath), GFP_KERNEL);
if (!ath)
return -ENOMEM;
bt_dev_dbg(hu->hdev, "hu %p", hu);
+ if (!hci_uart_has_flow_control(hu))
+ return -EOPNOTSUPP;
+
bcm = kzalloc(sizeof(*bcm), GFP_KERNEL);
if (!bcm)
return -ENOMEM;
BT_DBG("hu %p", hu);
+ if (!hci_uart_has_flow_control(hu))
+ return -EOPNOTSUPP;
+
intel = kzalloc(sizeof(*intel), GFP_KERNEL);
if (!intel)
return -ENOMEM;
return 0;
}
+/* Check the underlying device or tty has flow control support */
+bool hci_uart_has_flow_control(struct hci_uart *hu)
+{
+ /* serdev nodes check if the needed operations are present */
+ if (hu->serdev)
+ return true;
+
+ if (hu->tty->driver->ops->tiocmget && hu->tty->driver->ops->tiocmset)
+ return true;
+
+ return false;
+}
+
/* Flow control or un-flow control the device */
void hci_uart_set_flow_control(struct hci_uart *hu, bool enable)
{
BT_DBG("hu %p", hu);
+ if (!hci_uart_has_flow_control(hu))
+ return -EOPNOTSUPP;
+
mrvl = kzalloc(sizeof(*mrvl), GFP_KERNEL);
if (!mrvl)
return -ENOMEM;
BT_DBG("hu %p qca_open", hu);
+ if (!hci_uart_has_flow_control(hu))
+ return -EOPNOTSUPP;
+
qca = kzalloc(sizeof(struct qca_data), GFP_KERNEL);
if (!qca)
return -ENOMEM;
int hci_uart_init_ready(struct hci_uart *hu);
void hci_uart_init_work(struct work_struct *work);
void hci_uart_set_baudrate(struct hci_uart *hu, unsigned int speed);
+bool hci_uart_has_flow_control(struct hci_uart *hu);
void hci_uart_set_flow_control(struct hci_uart *hu, bool enable);
void hci_uart_set_speeds(struct hci_uart *hu, unsigned int init_speed,
unsigned int oper_speed);