On Wed, Feb 06, 2019 at 08:06:54AM +0100, Marcel Holtmann wrote: > Hi Myungho, > > >>> tiocmget() and tiocmset() operations are optional and some tty drivers > >>> like pty miss the operations. Add NULL checks to prevent from > >>> dereference. > >>> > >>> Myungho Jung (2): > >>> Bluetooth: hci_ath: Add NULL check for tiocmget() and tiocmset() in > >>> ath_setup() > >>> Bluetooth: hci_ldisc: Add NULL check for tiocmget() and tiocmset() in > >>> hci_uart_set_flow_control() > >>> > >>> drivers/bluetooth/hci_ath.c | 6 ++++++ > >>> drivers/bluetooth/hci_ldisc.c | 4 ++++ > >>> 2 files changed, 10 insertions(+) > >> > >> why are we not enforcing the availability of these in the > >> hci_uart_tty_open? > > > > Are the operations required on any HCI UART drivers? For now, I found only 5 > > drivers (ath, bcm, intel, mrvl, and qca) are explicitly calling them. So, > > I'm > > not sure whether it breaks any existing code with other drivers if returning > > error in open(). > > the H:4 spec requires setting flow control. In some cases this is done by the > hciattach or btattach utility, but it still means that it is required. So > failing on TTYs that don’t support it is just fine. > > Regards > > Marcel > Ok, let me make a change on hci_uart_tty_open().
Thanks, Myungho
