Per @zxzxwu review on #918:
- bumble/avdtp.py: replace `if len(pdu) < 1:` with `if not pdu:`
- tests/avdtp_test.py: replace `assert completed == []` with
`assert not completed`
Both are idiomatic Python truthy checks; behavior identical.
A remote peer can send an AVDTP frame shorter than the assembler expects.
The current MessageAssembler.on_pdu() unconditionally accesses pdu[0],
pdu[1], and (for START packets) pdu[2], so a 0-, 1-, or 2-byte frame
raises IndexError. The exception propagates up through L2CAP's read loop
and tears down the channel — same DoS class as #912 (empty ATT PDU) and
#914 (unbounded SDP recursion).
Fix: validate length before each access. Empty PDUs and packets shorter
than the type-specific minimum are logged and dropped; the assembler
stays alive so the L2CAP channel is not torn down.
- bumble/avdtp.py: length guards in MessageAssembler.on_pdu before
accessing pdu[0], pdu[1], pdu[2].
- tests/avdtp_test.py: regression test covering empty PDU, 1-byte SINGLE,
1-byte START, 2-byte START — all four would have raised IndexError
pre-fix; assembler now drops without raising.
* Add BaseBumbleException as a "real" root error
* Add several core error classes and properly replace builtin errors
with them
* Add several error classes for specific modules (transport, device)
[85542e0] fix test
[3748781] add ASAH sink example
[e782e29] add app
[83daa30] wip
[7f138a0] add test
[f732108] allow different address syntax
[9d0bbf8] rename deprecated methods
[eb303d5] add LE CoC support
