Patch "USB: serial: ftdi_sio: fix latency-timer error handling" has been added to the 3.18-stable tree

Patch "USB: serial: ftdi_sio: fix latency-timer error handling" has been added to the 3.18-stable tree

[gregkh]

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

    USB: serial: ftdi_sio: fix latency-timer error handling

to the 3.18-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-ftdi_sio-fix-latency-timer-error-handling.patch
and it can be found in the queue-3.18 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From e3e574ad85a208cb179f33720bb5f12b453de33c Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@kernel.org>
Date: Thu, 12 Jan 2017 14:56:12 +0100
Subject: USB: serial: ftdi_sio: fix latency-timer error handling

From: Johan Hovold <johan@kernel.org>

commit e3e574ad85a208cb179f33720bb5f12b453de33c upstream.

Make sure to detect short responses when reading the latency timer to
avoid using stale buffer data.

Note that no heap data would currently leak through sysfs as
ASYNC_LOW_LATENCY is set by default.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/usb/serial/ftdi_sio.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -1437,10 +1437,13 @@ static int read_latency_timer(struct usb
 			     FTDI_SIO_GET_LATENCY_TIMER_REQUEST_TYPE,
 			     0, priv->interface,
 			     buf, 1, WDR_TIMEOUT);
-	if (rv < 0)
+	if (rv < 1) {
 		dev_err(&port->dev, "Unable to read latency timer: %i\n", rv);
-	else
+		if (rv >= 0)
+			rv = -EIO;
+	} else {
 		priv->latency = buf[0];
+	}
 
 	kfree(buf);
 


Patches currently in stable-queue which might be from johan@kernel.org are

queue-3.18/usb-serial-mct_u232-fix-modem-status-error-handling.patch
queue-3.18/usb-serial-ark3116-fix-open-error-handling.patch
queue-3.18/usb-serial-io_edgeport-fix-epic-descriptor-handling.patch
queue-3.18/usb-serial-ti_usb_3410_5052-fix-control-message-error-handling.patch
queue-3.18/usb-serial-keyspan_pda-fix-receive-sanity-checks.patch
queue-3.18/usb-serial-sierra-fix-bogus-alternate-setting-assumption.patch
queue-3.18/usb-serial-ssu100-fix-control-message-error-handling.patch
queue-3.18/usb-serial-digi_acceleport-fix-incomplete-rx-sanity-check.patch
queue-3.18/usb-serial-io_edgeport-fix-descriptor-error-handling.patch
queue-3.18/usb-serial-quatech2-fix-control-message-error-handling.patch
queue-3.18/usb-serial-ftdi_sio-fix-latency-timer-error-handling.patch