UPSTREAM: usb: gadget: f_hid: fix: Prevent accessing released memory

When we unlock our spinlock to copy data to user we may get
disabled by USB host and free the whole list of completed out
requests including the one from which we are copying the data
to user memory.

To prevent from this let's remove our working element from
the list and place it back only if there is sth left when we
finish with it.

CVE-2018-9417

Change-Id: Idbf41652b00654ca53cb76c1c7c48d634c3fab40
Fixes: 99c515005857 ("usb: gadget: hidg: register OUT INT endpoint for SET_REPORT")
Cc: stable@vger.kernel.org
Tested-by: David Lechner <david@lechnology.com>
Signed-off-by: Krzysztof Opasiak <k.opasiak@samsung.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
1 file changed