43 lines
3.6 KiB
Markdown
43 lines
3.6 KiB
Markdown
---
|
|
id: "bug-1683"
|
|
status: "fixed"
|
|
status_updated: "2026-10-03"
|
|
status_note: ""
|
|
component: "xceadmin"
|
|
severity: "unknown"
|
|
timestamp: "2026-08-25T00:05:00Z"
|
|
last_seen: "2026-10-03T07:27:36Z"
|
|
occurrences: 3
|
|
files: ["src/xceadmin/src/xcecommon/wire.py"]
|
|
tags: ["xceadmin", "xcecommon", "wire-protocol", "python", "framing", "test-failure", "unreproducible"]
|
|
related: ["bug-1604"]
|
|
fix_commits: ["362098b1"]
|
|
legacy: true
|
|
---
|
|
|
|
# bug-1683: xceadmin pytest failure: test_send_frame_writes_exact_known_good_byte_sequence…
|
|
|
|
## Description
|
|
xceadmin pytest failure: test_send_frame_writes_exact_known_good_byte_sequence (src/xceadmin/tests/test_wire.py:200). Test sends a 4-byte payload b'xce!' via wire.send_frame() over a real TLS socket to a raw capture handler that reads exactly 12 bytes (8-byte length header + 4-byte payload) directly off the wire, bypassing this module's own recv_frame() decoder. Expected the captured bytes to be struct.pack('=Q', 4) + b'xce!' (header correctly encodes length=4, followed by the literal payload bytes). Actual captured bytes: the 8-byte header is correct (b'\x04\x00\x00\x00\x00\x00\x00\x00', i.e. length=4 little-endian native uint64_t), but the trailing 4 bytes are all zero (b'\x00\x00\x00\x00') instead of b'xce!' -- the real payload bytes never reached the wire. 1 failed, 266 passed, 3 skipped -- isolated to this one test.
|
|
|
|
UPDATE (2026-10-03): Correction: the trailing bytes were never zeroed -- pytest's truncated diff showed the 8-byte header alone. See Root cause (test-harness TLS RST race).
|
|
|
|
## Environment
|
|
_Not recorded (migrated from buglog.json)._
|
|
|
|
## Reproduction
|
|
_Not recorded (migrated from buglog.json)._
|
|
|
|
## Root cause
|
|
Corrected 2026-10-03, superseding the earlier "not reproducible / build-dir race (bug-1604)" analysis (kept in git history). Test-harness race in `src/xceadmin/tests/test_wire.py` `test_send_frame_writes_exact_known_good_byte_sequence`: the client called `send_frame()` and then `sock.close()` immediately. Under TLS 1.3 the server sends NewSessionTicket records after the handshake that the client never reads; closing a TCP socket with unread inbound data makes Linux send RST instead of FIN. Each `sendall()` is its own TLS record, so when the RST lands between the server's read of the 8-byte header record and the 4-byte payload record, the unread payload is discarded and `recv()` raises ConnectionResetError/BrokenPipeError, which `_TlsEchoServer._run` swallowed with a bare `pass` -- leaving `captured` = header only. The "4 zero bytes" in the original description was a misreading of pytest's truncated diff of the 8-byte header. `wire.send_frame()` is correct; production paths read the reply before closing and are not exposed.
|
|
|
|
## Fix
|
|
`test_wire.py` only: the client waits on a `capture_done` Event (set in the handler's `finally`) before `sock.close()`; `_TlsEchoServer` records the handler's OSError in `handler_error` (asserted None) instead of discarding it; the test is parametrized with `settle_s` [0.0, 0.05] (`immediate` / `tickets-pending`), the 0.05 case being a deterministic regression for the RST path. Fix commit 362098b1.
|
|
|
|
## Verification
|
|
- Test: `test_send_frame_writes_exact_known_good_byte_sequence[tickets-pending]` in `src/xceadmin/tests/test_wire.py` — RED before the fix (`assert b'\x04\x00...\x00' == b'\x04\x00...xce!'`; reviewer's scratch copy without the wait: 5/5 ConnectionResetError 104), GREEN after; 200 looped runs 0 failures; scratch harness 8/2000 natural failures before vs 0/2000 after.
|
|
- Suites: `bash src/tools/xce-build.sh xceadmin --incremental` 373 passed, 2026-10-03.
|
|
- Live: n/a
|
|
|
|
## References
|
|
- Related: bug-1604
|