tree 4b3c397851b5dda86621549c1ab67c277f5ac347
parent 749e69b5fb24381c4a83cebd0ab6599033b50bc2
author Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1505826437 +0200
committer Levente Tamas <ext-levente.tamas@nedevicesw.com> 1525786042 +0300

USB: fix out-of-bounds in usb_set_configuration

Andrey Konovalov reported a possible out-of-bounds problem for a USB interface
association descriptor.  He writes:
	It seems there's no proper size check of a USB_DT_INTERFACE_ASSOCIATION
	descriptor. It's only checked that the size is >= 2 in
	usb_parse_configuration(), so find_iad() might do out-of-bounds access
	to intf_assoc->bInterfaceCount.

And he's right, we don't check for crazy descriptors of this type very well, so
resolve this problem.  Yet another issue found by syzkaller...

Change-Id: I1fc3d88d58ad9ec5521679ee7c90ca1fa00d33c5
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>