USB: Fix off by one in type-specific length check of BOS SSP capability
authorMathias Nyman <mathias.nyman@linux.intel.com>
Tue, 19 Dec 2017 09:14:42 +0000 (11:14 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 2 Jan 2018 19:31:15 +0000 (20:31 +0100)
commitc7c4e00a66081ad6161f009a0c329b9a36085766
treea5fd15e1da0582303d0d3ae19a0e2689aee52a0d
parente2f33e5983cb1609805e267a3d2ef46d78257b2c
USB: Fix off by one in type-specific length check of BOS SSP capability

commit 07b9f12864d16c3a861aef4817eb1efccbc5d0e6 upstream.

USB 3.1 devices are not detected as 3.1 capable since 4.15-rc3 due to a
off by one in commit 81cf4a45360f ("USB: core: Add type-specific length
check of BOS descriptors")

It uses USB_DT_USB_SSP_CAP_SIZE() to get SSP capability size which takes
the zero based SSAC as argument, not the actual count of sublink speed
attributes.

USB3 spec 9.6.2.5 says "The number of Sublink Speed Attributes = SSAC + 1."

The type-specific length check patch was added to stable and needs to be
fixed there as well

Fixes: 81cf4a45360f ("USB: core: Add type-specific length check of BOS descriptors")
CC: Masakazu Mokuno <masakazu.mokuno@gmail.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/core/config.c