[patch 25/28] USB: cdc-acm: fix sysfs attribute registration bug

[Greg KH <gregkh@suse.de>]

[-- Attachment #1: usb-cdc-acm-fix-sysfs-attribute-registration-bug.patch --]
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-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Alan Stern <stern@rowland.harvard.edu>

This patch (as950) fixes a bug in the cdc-acm driver.  It doesn't keep
track of which interface (control or data) the sysfs attributes get
registered for, and as a result, during disconnect it will sometimes
attempt to remove the attributes from the wrong interface.  The
left-over attributes can cause a crash later on, particularly if the driver
module has been unloaded.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 drivers/usb/class/cdc-acm.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -900,6 +900,10 @@ next_desc:
 			return -ENODEV;
 		}
 	}
+
+	/* Accept probe requests only for the control interface */
+	if (intf != control_interface)
+		return -ENODEV;
 	
 	if (data_interface_num != call_interface_num)
 		dev_dbg(&intf->dev,"Seperate call control interface. That is not fully supported.");

--