Skip to content
  • Marcel Holtmann's avatar
    Bluetooth: Check L2CAP option sizes returned from l2cap_get_conf_opt · 82868814
    Marcel Holtmann authored
    commit af3d5d1c
    
     upstream.
    
    When doing option parsing for standard type values of 1, 2 or 4 octets,
    the value is converted directly into a variable instead of a pointer. To
    avoid being tricked into being a pointer, check that for these option
    types that sizes actually match. In L2CAP every option is fixed size and
    thus it is prudent anyway to ensure that the remote side sends us the
    right option size along with option paramters.
    
    If the option size is not matching the option type, then that option is
    silently ignored. It is a protocol violation and instead of trying to
    give the remote attacker any further hints just pretend that option is
    not present and proceed with the default values. Implementation
    following the specification and its qualification procedures will always
    use the correct size and thus not being impacted here.
    
    To keep the code readable and consistent accross all options, a few
    cosmetic changes were also required.
    
    Signed-off-by: default avatarMarcel Holtmann <marcel@holtmann.org>
    Reviewed-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    Signed-off-by: default avatarJohan Hedberg <johan.hedberg@intel.com>
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    82868814