diff options
| author | Johan Hovold <johan@kernel.org> | 2017-01-12 14:56:21 +0100 |
|---|---|---|
| committer | Johan Hovold <johan@kernel.org> | 2017-01-16 16:38:56 +0100 |
| commit | 5ed8d41023751bdd3546f2fe4118304357efe8d2 (patch) | |
| tree | cc59f9d4e1b211c7a3e893371c76ae9701f5b90a | |
| parent | 8c34cb8ddfe808d557b51da983ff10c02793beb2 (diff) | |
| download | blackbird-op-linux-5ed8d41023751bdd3546f2fe4118304357efe8d2.tar.gz blackbird-op-linux-5ed8d41023751bdd3546f2fe4118304357efe8d2.zip | |
USB: serial: spcp8x5: fix modem-status handling
Make sure to detect short control transfers and return zero on success
when retrieving the modem status.
This fixes the TIOCMGET implementation which since e1ed212d8593 ("USB:
spcp8x5: add proper modem-status support") has returned TIOCM_LE on
successful retrieval, and avoids leaking bits from the stack on short
transfers.
This also fixes the carrier-detect implementation which since the above
mentioned commit unconditionally has returned true.
Fixes: e1ed212d8593 ("USB: spcp8x5: add proper modem-status support")
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
| -rw-r--r-- | drivers/usb/serial/spcp8x5.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/drivers/usb/serial/spcp8x5.c b/drivers/usb/serial/spcp8x5.c index 475e6c31b266..ddfd787c461c 100644 --- a/drivers/usb/serial/spcp8x5.c +++ b/drivers/usb/serial/spcp8x5.c @@ -232,11 +232,17 @@ static int spcp8x5_get_msr(struct usb_serial_port *port, u8 *status) ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), GET_UART_STATUS, GET_UART_STATUS_TYPE, 0, GET_UART_STATUS_MSR, buf, 1, 100); - if (ret < 0) + if (ret < 1) { dev_err(&port->dev, "failed to get modem status: %d\n", ret); + if (ret >= 0) + ret = -EIO; + goto out; + } dev_dbg(&port->dev, "0xc0:0x22:0:6 %d - 0x02%x\n", ret, *buf); *status = *buf; + ret = 0; +out: kfree(buf); return ret; |
