From 0651f95d7e5b28b4ba483e3d171f89dd99fa509f Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Thu, 12 Jan 2017 14:56:09 +0100 Subject: [PATCH] USB: serial: ark3116: fix register-accessor error handling commit 9fef37d7cf170522fb354d6d0ea6de09b9b16678 upstream. The current implementation failed to detect short transfers, something which could lead to bits of the uninitialised heap transfer buffer leaking to user space. Fixes: 149fc791a452 ("USB: ark3116: Setup some basic infrastructure for new ark3116 driver.") Fixes: f4c1e8d597d1 ("USB: ark3116: Make existing functions 16450-aware and add close and release functions.") Reviewed-by: Greg Kroah-Hartman Signed-off-by: Johan Hovold Signed-off-by: Ben Hutchings --- drivers/usb/serial/ark3116.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/drivers/usb/serial/ark3116.c b/drivers/usb/serial/ark3116.c index 1a715f6587aa..41dab8b978e6 100644 --- a/drivers/usb/serial/ark3116.c +++ b/drivers/usb/serial/ark3116.c @@ -107,10 +107,17 @@ static int ark3116_read_reg(struct usb_serial *serial, usb_rcvctrlpipe(serial->dev, 0), 0xfe, 0xc0, 0, reg, buf, 1, ARK_TIMEOUT); - if (result < 0) + if (result < 1) { + dev_err(&serial->interface->dev, + "failed to read register %u: %d\n", + reg, result); + if (result >= 0) + result = -EIO; + return result; - else - return buf[0]; + } + + return buf[0]; } static inline int calc_divisor(int bps) -- 2.39.5