The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From de24e0a108bc48062e1c7acaa97014bce32a919f Mon Sep 17 00:00:00 2001 From: Johan Hovold <johan@xxxxxxxxxx> Date: Wed, 19 Oct 2016 15:45:07 +0200 Subject: [PATCH] USB: serial: cp210x: fix tiocmget error handling The current tiocmget implementation would fail to report errors up the stack and instead leaked a few bits from the stack as a mask of modem-status flags. Fixes: 39a66b8d22a3 ("[PATCH] USB: CP2101 Add support for flow control") Cc: stable <stable@xxxxxxxxxxxxxxx> Signed-off-by: Johan Hovold <johan@xxxxxxxxxx> diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c index 54a4de0efdba..f61477bed3a8 100644 --- a/drivers/usb/serial/cp210x.c +++ b/drivers/usb/serial/cp210x.c @@ -1077,7 +1077,9 @@ static int cp210x_tiocmget(struct tty_struct *tty) u8 control; int result; - cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control); + result = cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control); + if (result) + return result; result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0) |((control & CONTROL_RTS) ? TIOCM_RTS : 0) -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html