e251c59232
commit a246b4d547708f33ff4d4b9a7a5dbac741dc89d8 upstream.
Make sure to check that we have two alternate settings and at least one
endpoint before accessing the second altsetting structure and
dereferencing the endpoint arrays.
This specifically avoids dereferencing NULL-pointers or corrupting
memory when a device does not have the expected descriptors.
Note that the sanity check in cit_get_packet_size() is not redundant as
the driver is mixing looking up altsettings by index and by number,
which may not coincide.
Fixes: 659fefa0eb17 ("V4L/DVB: gspca_xirlink_cit: Add support for camera with a bcd version of 0.01")
Fixes: 59f8b0bf3c12 ("V4L/DVB: gspca_xirlink_cit: support bandwidth changing for devices with 1 alt setting")
Cc: stable <stable@vger.kernel.org> # 2.6.37
Cc: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.