commit b44be246 upstream.

Commit 3b74c73f switched over to memdup_user()
in ep_write() function and removed kfree (kbuf).
memdup_user() function allocates memory which is never freed.

Fixes: 3b74c73f (usb: gadget: inode: switch over to memdup_user())
Signed-off-by: Mario Schuknecht <mario.schuknecht@dresearch-fe.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>
[ luis: backported to 3.16:
  - file rename: drivers/usb/gadget/legacy/inode.c ->
    drivers/usb/gadget/inode.c ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>