Artifact Description [adc4ea5e22]

Artifact adc4ea5e22f821d868ffa57e3aafd42834f358b26d4b317cd6dbe8c76c6f733b:

• File src/transport_fuzz.zig
  • 2026-07-19 00:10:09 — part of check-in [cec4afaf89] on branch release-0.1 — Add transport_frame_garbage and serve_request_garbage seeded fuzz targets

    The 24 existing fuzz targets cover the delta, artifact, sync-parser and logstore layers, but not the two CLI-layer modules that consume bytes an untrusted remote peer chose. `sync_parsers_adversarial` covers the layer above; the HTTP framing itself was unfuzzed. These are the last two wire surfaces on the release bar, and they are what a hostile peer reaches first.

    What landed:

    - `src/transport_fuzz.zig` — `frameGarbage`, registered as `transport_frame_garbage`. Client-side §4/§4.1 framing and redirect policy: the round-trip law (whatever `frame` produces, `unframe` returns exactly those plaintext bytes), mutation of framed containers (bit damage never survives as *different* plaintext — it either fails the container's Adler-32/zlib checks or, in the length-field range the §4.1 compression-length erratum makes a capacity bound, decodes back to the same bytes), and garbage `Location` headers through `resolveRedirect`. Totality is the asserted contract: every input yields a value whose postconditions hold or a declared member of `TransportError`.

    - `src/serve_fuzz.zig` — `requestGarbage`, registered as `serve_request_garbage`. Server-side HTTP request path: raw bytes into `std.http.Server.receiveHead`, then `handleHttpRequest`'s dispatch (`classifyXfer` -> body read -> responder -> reply framing). It does not re-feed `handleXfer` in isolation — that decoding is already fuzzed twice — it reaches it only as the tail of a full-path dispatch, which is the point. Asserted contract: any `receiveHead` error is a clean rejection, `handleHttpRequest` returns void, and any produced response begins with an HTTP/1.1 status line.

    - `src/serve.zig`: `driveHttp` becomes `pub`. It is the request-path seam two callers need and neither should reimplement — the §4 smoke tests and this fuzz target. In-memory reader/writer on both sides, so the target binds no port and cannot flake in CI.

    - `src/fuzz_tests.zig`: both targets registered in the `targets` table, and `targets` becomes `pub` for a new structural registration pin. An unregistered target compiles, passes review, and is then never run by any invocation; the pin asserts every target the release bar names is actually reachable from the runner, so the registration cannot rot.

    - `src/dst.zig`: aggregates both new files plus `fuzz_tests.zig` into `zig build test`. This root is the one that reaches serve.zig and transport.zig relatively while carrying the `zit` dep those two import; `zig build fuzz` has no test step, so it is also the only place the registration pin can run.

    No bug found, so no fix and no pinned-seed regression in this commit — both surfaces held over the seeded runs below. The targets are the standing check, not a one-time sweep.

    Test evidence (this worktree, after `fossil update` absorbed the sibling `zit open` commit 5ba418801d and its 8 modified files):

    - `zig build fuzz -- transport_frame_garbage --seed 1 --rounds 2000` — clean, no crash/leak/UB. - `zig build fuzz -- serve_request_garbage --seed 1 --rounds 2000` — clean, no crash/leak/UB. - `zig build test` — green, including the new registration pin and the fixed-seed smoke tests at the foot of both new files. - `zig build` and `zig fmt --check .` — green.

    No borrowed technique in this change. (user: dmestas, size: 9372) [annotate] [blame] [check-ins using]

  • 2026-07-19 00:17:51 — part of check-in [b8db5ecabd] on branch trunk — Merge release-0.1: Add transport_frame_garbage and serve_request_garbage seeded fuzz targets

    Lands P4-F6, closing the last unfuzzed attack surface in the release scope. transport.zig and serve.zig are the only two files a remote peer can reach with bytes it fully controls, and neither had a fuzz target: the sync_parsers_adversarial target covers the layer above them, so the HTTP framing itself — the first code to touch untrusted input — was exercised only by hand-written smoke cases. These two targets hit that framing directly.

    The increment: src/transport_fuzz.zig (205 L) and src/serve_fuzz.zig (303 L), registered in the fuzz_tests.zig dispatch table alongside the existing 24 and pinned by that file's registration test. serve.zig's driveHttp is promoted to pub with a comment stating why — it is the receiveHead to handleHttpRequest seam the smoke tests and the fuzz target both need, and duplicating it would have meant fuzzing a copy of the request path rather than the real one. Both sides stay in-memory, so neither target binds a port and neither can flake in CI. dst.zig picks up the two targets plus fuzz_tests.zig itself, the latter so the registration pin has a test step to run in: zig build fuzz has none.

    Evidence, re-verified on the merged tree rather than on the branch, since trunk had advanced: zig fmt --check ., zig build, and zig build test each exit 0. Both new targets run clean seeded — invoking zig build fuzz with each target name and --seed 1 exits 0 for transport_frame_garbage and for serve_request_garbage — and found no crash, leak, or UB to fix, so this step carries no pinned-seed regression. The merge reported no conflicts; a repo-wide grep for conflict markers is clean, and fossil extras is empty, so both added files are tracked and nothing referenced went unadded. (user: dmestas, size: 9372) [annotate] [blame] [check-ins using]