On Tue, 2019-07-30 at 11:33 +0200, Marcel Holtmann wrote: > From: Vladis Dronov <vdronov@xxxxxxxxxx> > > 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@xxxxxxxxxxxxxxxxxxxxxxxxx > Cc: stable@xxxxxxxxxxxxxxx # 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@xxxxxxxxxx> > Signed-off-by: Marcel Holtmann <marcel@xxxxxxxxxxxx> Reviewed-by: Yu-Chen, Cho <acho@xxxxxxxx> Tested-by: Yu-Chen, Cho <acho@xxxxxxxx> > --- > drivers/bluetooth/hci_ath.c | 3 +++ > drivers/bluetooth/hci_bcm.c | 3 +++ > drivers/bluetooth/hci_intel.c | 3 +++ > drivers/bluetooth/hci_ldisc.c | 13 +++++++++++++ > drivers/bluetooth/hci_mrvl.c | 3 +++ > drivers/bluetooth/hci_qca.c | 3 +++ > drivers/bluetooth/hci_uart.h | 1 + > 7 files changed, 29 insertions(+) > > diff --git a/drivers/bluetooth/hci_ath.c > b/drivers/bluetooth/hci_ath.c > index a55be205b91a..dbfe34664633 100644 > --- a/drivers/bluetooth/hci_ath.c > +++ b/drivers/bluetooth/hci_ath.c > @@ -98,6 +98,9 @@ static int ath_open(struct hci_uart *hu) > > BT_DBG("hu %p", hu); > > + if (!hci_uart_has_flow_control(hu)) > + return -EOPNOTSUPP; > + > ath = kzalloc(sizeof(*ath), GFP_KERNEL); > if (!ath) > return -ENOMEM; > diff --git a/drivers/bluetooth/hci_bcm.c > b/drivers/bluetooth/hci_bcm.c > index 8905ad2edde7..ae2624fce913 100644 > --- a/drivers/bluetooth/hci_bcm.c > +++ b/drivers/bluetooth/hci_bcm.c > @@ -406,6 +406,9 @@ static int bcm_open(struct hci_uart *hu) > > 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; > diff --git a/drivers/bluetooth/hci_intel.c > b/drivers/bluetooth/hci_intel.c > index 207bae5e0d46..31f25153087d 100644 > --- a/drivers/bluetooth/hci_intel.c > +++ b/drivers/bluetooth/hci_intel.c > @@ -391,6 +391,9 @@ static int intel_open(struct hci_uart *hu) > > BT_DBG("hu %p", hu); > > + if (!hci_uart_has_flow_control(hu)) > + return -EOPNOTSUPP; > + > intel = kzalloc(sizeof(*intel), GFP_KERNEL); > if (!intel) > return -ENOMEM; > diff --git a/drivers/bluetooth/hci_ldisc.c > b/drivers/bluetooth/hci_ldisc.c > index 8950e07889fe..85a30fb9177b 100644 > --- a/drivers/bluetooth/hci_ldisc.c > +++ b/drivers/bluetooth/hci_ldisc.c > @@ -292,6 +292,19 @@ static int hci_uart_send_frame(struct hci_dev > *hdev, struct sk_buff *skb) > 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) > { > diff --git a/drivers/bluetooth/hci_mrvl.c > b/drivers/bluetooth/hci_mrvl.c > index f98e5cc343b2..fbc3f7c3a5c7 100644 > --- a/drivers/bluetooth/hci_mrvl.c > +++ b/drivers/bluetooth/hci_mrvl.c > @@ -59,6 +59,9 @@ static int mrvl_open(struct hci_uart *hu) > > BT_DBG("hu %p", hu); > > + if (!hci_uart_has_flow_control(hu)) > + return -EOPNOTSUPP; > + > mrvl = kzalloc(sizeof(*mrvl), GFP_KERNEL); > if (!mrvl) > return -ENOMEM; > diff --git a/drivers/bluetooth/hci_qca.c > b/drivers/bluetooth/hci_qca.c > index 9a5c9c1f9484..82a0a3691a63 100644 > --- a/drivers/bluetooth/hci_qca.c > +++ b/drivers/bluetooth/hci_qca.c > @@ -473,6 +473,9 @@ static int qca_open(struct hci_uart *hu) > > 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; > diff --git a/drivers/bluetooth/hci_uart.h > b/drivers/bluetooth/hci_uart.h > index f11af3912ce6..6ab631101019 100644 > --- a/drivers/bluetooth/hci_uart.h > +++ b/drivers/bluetooth/hci_uart.h > @@ -104,6 +104,7 @@ int hci_uart_wait_until_sent(struct hci_uart > *hu); > 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);
