Patch "USB: serial: io_edgeport: fix descriptor error handling" has been added to the 4.4-stable tree

[<gregkh@linuxfoundation.org>]

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

    USB: serial: io_edgeport: fix descriptor error handling

to the 4.4-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-io_edgeport-fix-descriptor-error-handling.patch
and it can be found in the queue-4.4 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 3c0e25d883d06a1fbd1ad35257e8abaa57befb37 Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@kernel.org>
Date: Thu, 12 Jan 2017 14:56:14 +0100
Subject: USB: serial: io_edgeport: fix descriptor error handling

From: Johan Hovold <johan@kernel.org>

commit 3c0e25d883d06a1fbd1ad35257e8abaa57befb37 upstream.

Make sure to detect short control-message transfers and log an error
when reading incomplete manufacturer and boot descriptors.

Note that the default all-zero descriptors will now be used after a
short transfer is detected instead of partially initialised ones.

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/io_edgeport.c |   24 +++++++++++++++---------
 1 file changed, 15 insertions(+), 9 deletions(-)

--- a/drivers/usb/serial/io_edgeport.c
+++ b/drivers/usb/serial/io_edgeport.c
@@ -2109,8 +2109,7 @@ static int rom_write(struct usb_serial *
  * rom_read
  *	reads a number of bytes from the Edgeport device starting at the given
  *	address.
- *	If successful returns the number of bytes read, otherwise it returns
- *	a negative error number of the problem.
+ *	Returns zero on success or a negative error number.
  ****************************************************************************/
 static int rom_read(struct usb_serial *serial, __u16 extAddr,
 					__u16 addr, __u16 length, __u8 *data)
@@ -2135,12 +2134,17 @@ static int rom_read(struct usb_serial *s
 					USB_REQUEST_ION_READ_ROM,
 					0xC0, addr, extAddr, transfer_buffer,
 					current_length, 300);
-		if (result < 0)
+		if (result < current_length) {
+			if (result >= 0)
+				result = -EIO;
 			break;
+		}
 		memcpy(data, transfer_buffer, current_length);
 		length -= current_length;
 		addr += current_length;
 		data += current_length;
+
+		result = 0;
 	}
 
 	kfree(transfer_buffer);
@@ -2597,9 +2601,10 @@ static void get_manufacturing_desc(struc
 				EDGE_MANUF_DESC_LEN,
 				(__u8 *)(&edge_serial->manuf_descriptor));
 
-	if (response < 1)
-		dev_err(dev, "error in getting manufacturer descriptor\n");
-	else {
+	if (response < 0) {
+		dev_err(dev, "error in getting manufacturer descriptor: %d\n",
+				response);
+	} else {
 		char string[30];
 		dev_dbg(dev, "**Manufacturer Descriptor\n");
 		dev_dbg(dev, "  RomSize:        %dK\n",
@@ -2656,9 +2661,10 @@ static void get_boot_desc(struct edgepor
 				EDGE_BOOT_DESC_LEN,
 				(__u8 *)(&edge_serial->boot_descriptor));
 
-	if (response < 1)
-		dev_err(dev, "error in getting boot descriptor\n");
-	else {
+	if (response < 0) {
+		dev_err(dev, "error in getting boot descriptor: %d\n",
+				response);
+	} else {
 		dev_dbg(dev, "**Boot Descriptor:\n");
 		dev_dbg(dev, "  BootCodeLength: %d\n",
 			le16_to_cpu(edge_serial->boot_descriptor.BootCodeLength));


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

queue-4.4/usb-serial-mct_u232-fix-modem-status-error-handling.patch
queue-4.4/usb-serial-ark3116-fix-open-error-handling.patch
queue-4.4/usb-serial-io_edgeport-fix-epic-descriptor-handling.patch
queue-4.4/usb-serial-ti_usb_3410_5052-fix-control-message-error-handling.patch
queue-4.4/usb-serial-keyspan_pda-fix-receive-sanity-checks.patch
queue-4.4/usb-serial-sierra-fix-bogus-alternate-setting-assumption.patch
queue-4.4/usb-serial-ssu100-fix-control-message-error-handling.patch
queue-4.4/usb-serial-digi_acceleport-fix-incomplete-rx-sanity-check.patch
queue-4.4/usb-serial-io_edgeport-fix-descriptor-error-handling.patch
queue-4.4/usb-serial-quatech2-fix-control-message-error-handling.patch
queue-4.4/usb-serial-ftdi_sio-fix-latency-timer-error-handling.patch