Patch "USB: serial: mct_u232: fix modem-status error handling" has been added to the 4.9-stable tree

This is a note to let you know that I've just added the patch titled

USB: serial: mct_u232: fix modem-status error handling

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
usb-serial-mct_u232-fix-modem-status-error-handling.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Johan Hovold <[email protected]>
Date: Thu, 12 Jan 2017 14:56:16 +0100
Subject: USB: serial: mct_u232: fix modem-status error handling

From: Johan Hovold <[email protected]>

commit 36356a669eddb32917fc4b5c2b9b8bf80ede69de upstream.

Make sure to detect short control-message transfers so that errors are logged when reading the modem status at open.

Note that while this also avoids initialising the modem status using uninitialised heap data, these bits could not leak to user space as they are currently not used.

---
 drivers/usb/serial/mct_u232.c |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

@@ -322,8 +322,12 @@ static int mct_u232_get_modem_stat(struc
 			MCT_U232_GET_REQUEST_TYPE,
 			0, 0, buf, MCT_U232_GET_MODEM_STAT_SIZE,
 			WDR_TIMEOUT);
-	if (rc < 0) {
+	if (rc < MCT_U232_GET_MODEM_STAT_SIZE) {
 		dev_err(&port->dev, "Get MODEM STATus failed (error = %d)\n", rc);
+
+		if (rc >= 0)
+			rc = -EIO;
+
 		*msr = 0;
 	} else {
 		*msr = buf[0];

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/usb-serial-mct_u232-fix-modem-status-error-handling.patch queue-4.9/usb-serial-ark3116-fix-open-error-handling.patch queue-4.9/usb-serial-io_edgeport-fix-epic-descriptor-handling.patch queue-4.9/usb-serial-ti_usb_3410_5052-fix-control-message-error-handling.patch queue-4.9/usb-serial-keyspan_pda-fix-receive-sanity-checks.patch queue-4.9/usb-serial-sierra-fix-bogus-alternate-setting-assumption.patch queue-4.9/usb-serial-ssu100-fix-control-message-error-handling.patch queue-4.9/usb-serial-digi_acceleport-fix-incomplete-rx-sanity-check.patch queue-4.9/usb-serial-io_edgeport-fix-descriptor-error-handling.patch queue-4.9/usb-serial-quatech2-fix-control-message-error-handling.patch queue-4.9/usb-serial-ftdi_sio-fix-latency-timer-error-handling.patch