btle: Correctly detect l2cap fragment start

The first L2CAP PDU fragment starts with the 4 octet long L2CAP header
consisting of the Length and the CID fields. The Length field doesn't
include the header itself. Thus the Length field in the BLE Data header
will be 4 octets larger than the L2CAP PDU header Length field if the
packet wouldn't be fragmented.

The current implementation doesn't correctly detect the start fragment
causing reassembly to fail as it compares the BLE Data Length with the
L2CAP Length without compensating for the header.

By increasing the L2CAP PDU Length field with the header length the
reassembly works.

Rename the variable to better reflect what length it actually
represents.

Bug: 15807
Change-Id: Idcb6bdccc4daae756a63a9bae0839fe25ae99f23
Reviewed-on: https://code.wireshark.org/review/33428
Petri-Dish: Stig Bjørlykke <stig@bjorlykke.org>
Reviewed-by: Stig Bjørlykke <stig@bjorlykke.org>

0 files changed, 0 insertions, 0 deletions