USB: cdc-acm: more sanity checking

USB: cdc-acm: more sanity checking

[ Upstream commit 8835ba4a39cf53f705417b3b3a94eb067673f2c9 ]

An attack has become available which pretends to be a quirky
device circumventing normal sanity checks and crashes the kernel
by an insufficient number of interfaces. This patch adds a check
to the code path for quirky devices.

Signed-off-by: Oliver Neukum <ONeukum@suse.com>
CC: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>