GitNexus/gitnexus/src
Gergő Magyar 14397dd4aa
feat(taint): intra-procedural taint analysis (#2083) (#2164)
* feat(taint): harvest occurrence-tagged call/member sites on StatementFacts (#2083 U1)

Worker-side site harvest in TsHarvester: call/new/member-read records with
dotted callee paths, receiver slots, per-argument occurrence tagging with
nested-site links, per-declarator resultDefs, spread/template/require-literal
markers. hasTaintSafeSites validation seam. The pdg parse-cache chunk-key
namespace is versioned (pdg:1 -> pdg:2) instead of a global SCHEMA_BUMP so
flag-off users keep warm caches; bench fingerprints re-baselined for the
three call-bearing scenarios (straight-line/dense-bindings byte-unchanged).

* feat(taint): built-in TS/JS source/sink/sanitizer model + site matcher (#2083 U2)

Typed spec (kind taxonomy; sanitizers carry neutralizes-kinds), the canonical
Express/Node model, and matchFunctionSites: ESM alias/namespace + require-
literal callee resolution, bare-name fallback restricted to true globals,
sanitizers module-or-global only (never user-shadowable by name), spread/
template arg-position rules, deterministic taintModelVersion.

* feat(taint): pure intra-procedural taint propagation engine (#2083 U3)

Two-rule model (statement-local + du-fact worklist) with per-taint
neutralized-kind exclusion sets: sanitizers exclude only the sink kinds
they neutralize (escape(req.body) suppresses res.send but still fires
db.query; exec(path.basename(t)) fires), intersection-over-paths so a
bypass occurrence keeps the taint live, kill locality on resultDefs,
propagate-through args+receiver with viaCall hops, one path per finding,
deterministic caps, coverage-gap statuses. Test-first: 38 scenarios on
real harvested CFGs.

* feat(taint): thread taint caps + model version through pdg config/meta (#2083 U5)

resolvePdgConfig gains maxTaintFindingsPerFunction (200), maxTaintHops (32),
and the taintModelVersion digest; RepoMeta.pdg + RunScopeResolutionInput
surfaces added. The key-union comparator trips full writeback on M2->M3
upgrade and on model-version change without --force (mode-flip tested).
No CLI flags or rc keys (programmatic parity with the other caps).

* feat(taint): in-phase taint emit with sparse TAINTED/SANITIZES edges (#2083 U4)

run.ts pdg window: match-first fast path (solver only when a function has
both a matched source and sink) -> computeReachingDefs with the shared RD
fact derivation -> computeTaintFlows -> per-finding TAINTED (versioned
hop-encoded reason via the shared path codec, statement-level occurrence
identity) + per-kill SANITIZES, dedup-before-budget, truncate-and-warn.
All emit counters surfaced (aggregate warn for gaps/drops, debug for
volume); PROF gains taint=. Flag-off golden untouched.

* feat(mcp): explain tool for persisted taint findings (#2083 U6)

Anchorless calls enumerate the sparse TAINTED table (bounded, deterministic,
limit-clamped); anchored calls (file or symbol via resolveSymbolCandidates)
return full decoded hop detail. sinkKind rides a version-1 codec header
(1;<kind>|hops — no other persisted channel exists; U4/U6 ship together).
RepoMeta.pdg probe yields a no-taint-layer note instead of an error.
TAINTED/SANITIZES pinned OUT of VALID_RELATION_TYPES (KTD9a negative-
membership tests); generators + canonical skill docs + mirrors updated.

* test(taint): acceptance fixture battery, snapshots, and bench gates (#2083 U7)

pdg-repo taint-cases fixtures complete the six plan shapes; committed
findings/kills snapshot via a shared pure-path harness that also feeds the
AE2 exact-equality assertion (stored TAINTED == pure-path findings, the
no-explosion gate). New taint-dense bench scenario with four --check gates:
per-function findings pinned AT the cap, absolute reason-byte + site-bytes
disk ceilings (the load-bearing R10 gate), zero-match pass < 0.5x match-
dense, N-linearity. Pre-existing scenario baselines untouched.

* refactor(taint): share one pointKey helper across propagate + emit (#2083 review)

Extract pointKey(ProgramPoint) to cfg/reaching-defs.ts (colon-separated,
matching the codebase block:stmt id convention) and import it in both
propagate.ts and emit.ts, replacing the two divergent locals (':' vs '.').
Edge-id material now uses the colon form; ids are in-memory only and no
test asserts the pointKey segment shape.

* fix(taint): discriminate taint state by source occurrence (#2083 review)

Two distinct sources flowing into one variable at one def point no longer
collapse to a single TAINTED edge: the taint-state key gains a root
source-occurrence discriminator ({point, siteIndex} — the same fields
recordFinding's identity uses, excluding kind). Def->use fact lookup keys
on the source-independent (binding, def-point) portion. Same-source
multi-path flows still share one state so their exclusion sets intersect
(the raw arm soundly wins); termination holds (finite keys, monotone
shrink, no cross-source ping-pong). Restores the KTD6 identity contract.

* fix(mcp): route dotted symbol names in explain to symbol resolution (#2083 review)

The fileish classifier matched any dotted name (UserController.create)
as a file via its extension-like suffix, so symbol resolution never ran
and the tool returned a silent empty file-anchored result. Tighten the
classifier to require a path separator or a real source extension (derived
from the resolver's EXTENSIONS list, multi-language), so dotted/bare names
route to resolveSymbolCandidates (found / ambiguous / not-found).

* fix(mcp): gate explain no-taint-layer note on taintModelVersion (#2083 review)

An M1/M2-era --pdg index has meta.pdg defined (BasicBlock/REACHING_DEF
recorded) but no taintModelVersion and zero TAINTED rows. The probe keyed
on generic meta.pdg presence, so explain returned the generic empty note
instead of the actionable 'no taint layer — run analyze' hint. Gate on
meta.pdg?.taintModelVersion (the field M3 stamps) so an M2-era index gets
the layer hint; a taint-stamped index with no findings still gets the
generic note.

* fix(taint): sequence-expression value flows only the final operand (#2083 review)

A comma expression in value position (exec((log(x), 'safe'))) default-
descended, fanning every operand's occurrences into the enclosing sink
argument — over-tainting exec's arg 0 with x. Add an explicit walkValue
case that records earlier operands' uses with occurrence fan-out suppressed
(new FactAccumulator.suppressOccurrences) and routes only the last operand
through the value path. Sites-layer only; defs/uses/mayDefs byte-identical
(cfg + reaching-defs snapshots unchanged).

* perf(taint): FIFO head-cursor worklist + dedup before chainHops (#2083 review)

Replace queue.shift() (O(N) dequeue) with a strict-FIFO head cursor plus
order-preserving prefix reclamation; FIFO is load-bearing because chainHops
reads the live taints map whose parent/source/viaCall are rewritten
order-sensitively on monotone shrink, so hop determinism is dequeue-order
contingent. Extract findingKey() and dedup-check before chainHops in the
justify branch — already-recorded identities discard their hop chain
(first write wins), so the ancestry walk was pure waste. The else kill
branch is untouched. Findings + hops byte-identical (snapshot unchanged).

* perf(taint): O(1) member-read dedup via composite-key set (#2083 review)

addMemberRead rescanned the whole per-statement sites array per call to
dedup by (object, property, parent) — O(n^2) on member-read-dense
statements. Track a composite-key Set alongside sites for O(1) dedup.
(The require-literal join is already O(sites) with a no-op body on
non-require sites, so no early-exit is needed there.) Behavior identical:
harvest + model-match + taint snapshots unchanged.

* refactor(taint): drop test-only export; source taint caps via emit.ts (#2083 review)

Remove the sanitizerNeutralizes export (its only consumers were two test
assertions — inlined to entry.neutralizes membership). Re-export the
DEFAULT_PDG_MAX_TAINT_* caps from emit.ts and point run.ts at emit.ts, so
the pipeline's taint dependency surface is the single orchestration module
rather than reaching into propagate.ts.

* test(taint): extract the shared TS CFG/taint test harness (#2083 review)

The parse/collectFunctions/cfgOf/cfgsOf/importsFor harness was copied
byte-for-byte across four suites (harvest, model-match, propagate,
taint-emit). Promote it to test/helpers/ts-cfg-harness.ts and import it.
site-safety/reaching-defs carry a structurally different inlined builder
and are left as-is. Pure extraction, no assertion changes.

* test(mcp): harden explain limit-rejection battery (#2083 review)

Add NaN, Infinity, -Infinity, and a numeric string to the out-of-bounds
limit cases — a regression fence over the interpolated LIMIT, confirming
the Number.isInteger guard rejects every non-integer/non-finite/string
input before it reaches the query.
2026-06-12 07:35:09 +01:00
..
cli feat(taint): intra-procedural taint analysis (#2083) (#2164) 2026-06-12 07:35:09 +01:00
config fix(worker): analyze native worker aborts (#1833) 2026-05-26 17:28:39 +01:00
core feat(taint): intra-procedural taint analysis (#2083) (#2164) 2026-06-12 07:35:09 +01:00
lib feat: configure prettier with pre-commit hook (#563) 2026-03-28 14:58:04 +00:00
mcp feat(taint): intra-procedural taint analysis (#2083) (#2164) 2026-06-12 07:35:09 +01:00
server fix(web): replace broken Browse-for-folder with upload directory picker (#1850) 2026-06-10 20:50:59 +01:00
storage feat(taint): intra-procedural taint analysis (#2083) (#2164) 2026-06-12 07:35:09 +01:00
types fix(parse): correct worker-pool docs drift + surface worker-side stack on crash (#2068) (#2070) 2026-06-08 07:20:12 +01:00