[robobun]

Fixes #44201

Problem

• A zstd compressor with ZSTD_c_nbWorkers >= 1 and a dictionary reads freed memory when the stream goes away while a worker job runs: heap-use-after-free in ZSTDMT_compressionJob. destroy(), close() and reset() reach it.
• zstd frees the dictionary before it joins its workers: ZSTD_clearAllDicts, then ZSTDMT_freeCCtx (lib/compress/zstd_compress.c:174).
• Context::close (src/runtime/node/zlib/NativeZstd.rs:652) also reset the context first, which frees the dictionary with no join.

Fix

• patches/zstd/free-workers-before-dictionaries.patch moves ZSTD_clearAllDicts after ZSTDMT_freeCCtx, which joins the workers.
• Context::close frees the context with no reset. Each edit alone leaves a free before the join.
• Verified: test/js/node/zlib/zlib-handle-bounds-check.test.ts, 7 new rows. Main fails 6 under ASAN, 5 on a release build. This PR: 0.
• Self-reviewed: 8 concerns raised, 8 addressed.

Background

• With workers, ZSTD_compressStream2 posts a job to threads of the context and returns before the job ends.
• Job 0 of a frame reads the dictionary through job->cdict, which it does not own.
• Considered: a join exported from zstd and a wait inside ZSTD_clearAllDicts. Both add work per close. The order swap adds none.

Downsides

• A teardown mid-job still blocks the JS thread until the job ends, as on main and in Node: 55 s at level 19 (node:zlib: destroy() of a zstd compressor with ZSTD_c_nbWorkers blocks the JS thread until the running job ends #44408).
• An async zstd write completes with 7 more instructions (148 to 155), because the linker now inlines close_internal there.
• Bun carries a second zstd patch, not reported upstream yet. With workers, a chunk larger than one job is still lost (node:zlib: a zstd compressor with ZSTD_c_nbWorkers gives no output for a chunk larger than one job #44257).

Notes

The rows. Each row of the new block leaves job 0 of a frame on a worker and then takes one way out of the stream, in a subprocess. Rows that fail, linux x64:

Build	Debug + ASAN	Release, no sanitizer
main 4b02e10	6: destroy(), close(), destroy() while the write is in flight, a second _handle.init(), reset() and the next frame, close() while a job of zero bytes runs	5: the same without the zero-byte row
src/ of main, with the zstd patch	4: destroy(), close(), destroy() while the write is in flight, the zero-byte row	3: the same without the zero-byte row
this PR without the zstd patch	6	not built
this PR	0 (whole file: 46 pass)	0

• Under ASAN a row fails with exit code 1 (the sanitizer report) or by the 5 s limit, because the report takes 4 to 5 s on the loaded build host. On a release build a row fails with exit code 139.
• ASAN reports the read in every run. The release failure depends on time: the dictionary is 192 KiB so that the allocator gives its freed tables back to the operating system while the job still searches them. With a dictionary of 123 bytes the rows pass on an unfixed release build (5 of 5 runs). The zero-byte row is seen by a sanitizer only.
• The rows run in sequence. As a concurrent block, 5 of the 7 rows passed the 5 s limit on the debug build of this branch at load 240, and in sequence they took 0.9 to 1.9 s.
• The finalizer is not a row, because the GC decides when it runs. By hand, with an earlier state of the rows (a 123-byte dictionary, ASAN): a stream dropped mid-job, then Bun.gc(true) or process exit. Main reports the use-after-free 4 of 6 and 2 of 6 times, this PR 0 of 6 and 0 of 6.

Reach without destroy() in user code. zlib.zstdCompress(input, { dictionary, params }, callback) with workers and an input larger than one job ends its stream early (#44257) and closes it while the job runs. Node v26.3.0 (zstd 1.5.7, the same order) ends with a segmentation fault 3 of 3 times for that call with a 192 KiB dictionary at level 19.

#44261 (reset() in place). It keeps the dictionary and the workers across reset(). Measured with its diff applied locally, with an earlier state of the rows (a 123-byte dictionary, and one more row: reset(), a write, destroy()):

• This PR plus node:zlib: reset a zstd stream in place, keep its dictionary and parameters #44261: the rows pass, and the tests of node:zlib: reset a zstd stream in place, keep its dictionary and parameters #44261 pass (13 and 3).
• node:zlib: reset a zstd stream in place, keep its dictionary and parameters #44261 alone: 6 rows fail, the extra row among them. That row passes on main, where reset() makes a new context with no dictionary and no workers, so it is not in this PR. It belongs to whichever of the two PRs lands second.
• Both PRs edit the patches array in scripts/build/deps/zstd.ts. Keep all three entries.
• This PR deletes the extern ZSTD_CCtx_reset from src/zstd/lib.rs, because nothing calls it any more. node:zlib: reset a zstd stream in place, keep its dictionary and parameters #44261 calls it, so the PR that lands second puts it back when it resolves the conflict in the patches array.
• node:zlib: one failure path for zstd and brotli init(): close, call onerror, throw #38684 edits init in the same file. A trial merge with this branch has no conflict.

Not covered in zstd. ZSTD_CCtx_reset with parameters, ZSTD_CCtx_loadDictionary, ZSTD_CCtx_refCDict and ZSTD_CCtx_refPrefix free the dictionaries too, with no join. After this PR bun calls none of them on a context whose jobs can still run: init makes a new context, and the reset of #44261 is a session reset, which keeps the dictionary.

Upstream. The dev branch of facebook/zstd (01b7154f11) has the same order, and no issue there reports it (checked 2026-10-01). The patch header says so. No report is filed yet. scripts/build/workarounds.ts has an entry for the patch: a bump of the zstd pin fails configure until someone reads ZSTD_freeCCtxContent() at the new commit and removes the patch or moves the entry.

Costs, measured. Release builds of the merge base and of this branch, same build directory and toolchain.

• Size (llvm-size): text 80,705,705 to 80,705,193 B. 8 of 80,257 text symbols change size (llvm-nm -S). Context::close 470 to 86 B, drop_glue<Box<NativeZstd>> 890 to 532 B, ZSTD_compress 1278 to 1275 B. close_internal<NativeZstd> (709 B) is now inlined into its three callers, which grow by 7, 317 and 362 B, and NativeZstdPrototype__close becomes a symbol of 345 B.
• Calls per 1,000 createZstdCompress().destroy() (gdb breakpoints with ignore counts): ZSTD_CCtx_reset 2000 to 1000, ZSTD_clearAllDicts 3000 to 2000, ZSTD_freeCCtx 1000 to 1000. For a decompressor: ZSTD_DCtx_reset 1000 to 0.
• Instructions per native close() (gdb stepi, from the entry of the host function to its return, callees included): compressor 271 to 213, calls 6 to 5. Decompressor 139 to 119.
• Write path (llvm-objdump -d, absolute addresses masked): 0 differing instructions in NativeZstdPrototype__write, NativeZstdPrototype__writeSync, NativeZstdPrototype__init, ZSTD_compressStream2 and ZSTD_decompressStream.
• run_from_js_thread<NativeZstd>, the completion of an async write: 148 to 155 of its own instructions, the same 3 calls.
• zstd_compress.c alone (clang 23, release flags without LTO): text 66,460 to 66,457 B. ZSTD_freeCCtx has 65 instructions before and after, with the call moved.
• Time that one teardown call blocks the JS thread (one worker, default job size, the call right after the write callback, 3 runs at levels 3 and 9): level 3, 51 to 176 ms on main, 98 to 185 ms here, 83 to 243 ms on Node v26.3.0. Level 9, 474 to 1042 ms, 492 to 620 ms, 480 to 1034 ms. Level 19, 54.8 s, 54.8 s, 58.3 s (one run each). The host load was 200 to 260.
• The futex count of a free in the middle of a job is not measured: strace is not installed on the build host. The patch moves one call and adds none.

Self-review. What changed after it: the dictionary of the rows is 192 KiB (the rows passed on an unfixed release build before), the comments name the sanitizer as the check and not the allocator of libc, one row that passed on main went out, the numbers above are those of the committed rows, the blocking teardown has numbers and an issue (#44408), and #44257 is named. The rows stay in sequence, with the measured reason above. One note of the review is not taken: an upstream zstd report (not filed yet). After the review bots on this PR: the comment about the removed reset is gone, the ZSTD_CCtx_reset extern is deleted, and the patch has an entry in the workaround registry.

Suites on the debug + ASAN build of this branch. zlib-handle-bounds-check.test.ts 46 pass. On the same source change before the branch moved to today's main: zlib.test.js 418 pass 2 skip, zlib-reset-race 5, zlib-estimated-size-gc 6, leak 8, zlib-onerror-reentrancy 3, bytesWritten 5, deflate-streaming 1, test/js/web/streams/compression* 73, test/js/bun/util/zstd.test.ts 96.

---

[policy-decision:dep] gate passed · iteration 0 · 6 files touched

fails on main (without fix)

ASAN without fix: 4 FAILED
$ BUN_DEBUG_QUIET_LOGS=1 bun scripts/build.ts --profile=debug --quiet test "--reporter=junit" "--reporter-outfile=/tmp/pr_gate.xml" test/js/node/zlib/zlib-handle-bounds-check.test.ts
bun test v1.4.3 (367d939d9)

test/js/node/zlib/zlib-handle-bounds-check.test.ts:
(pass) zlib native handle bounds checking > writeSync rejects in_len exceeding input buffer [138.99ms]
(pass) zlib native handle bounds checking > writeSync rejects out_len exceeding output buffer [6.85ms]
(pass) zlib native handle bounds checking > writeSync rejects in_off + in_len exceeding input buffer [4.76ms]
(pass) zlib native handle bounds checking > writeSync rejects out_off + out_len exceeding output buffer [4.38ms]
(pass) zlib native handle bounds checking > writeSync allows valid bounds [4.19ms]
(pass) zlib native handle bounds checking > writeSync allows valid offset + length within bounds [4.50ms]
(pass) zlib native handle bounds checking > writeSync allows null input (flush only) [3.99ms]
(pass) zlib native handle writeState > writeSync updates the writeState array [4.07ms]
(pass) zlib native handle writeState > write completion with a detached writeState backing store does not crash [967.23ms
... (truncated)

release without fix: 5 FAILED
bun test v1.4.3-canary.1 (367d939d9)

test/js/node/zlib/zlib-handle-bounds-check.test.ts:
(pass) zlib native handle bounds checking > writeSync rejects in_len exceeding input buffer [2.97ms]
(pass) zlib native handle bounds checking > writeSync rejects out_len exceeding output buffer [0.25ms]
(pass) zlib native handle bounds checking > writeSync rejects in_off + in_len exceeding input buffer [0.22ms]
(pass) zlib native handle bounds checking > writeSync rejects out_off + out_len exceeding output buffer [0.13ms]
(pass) zlib native handle bounds checking > writeSync allows valid bounds [0.14ms]
(pass) zlib native handle bounds checking > writeSync allows valid offset + length within bounds [0.15ms]
(pass) zlib native handle bounds checking > writeSync allows null input (flush only) [0.12ms]
(pass) zlib native handle writeState > writeSync updates the writeState array [0.21ms]
(pass) zlib native handle writeState > write completion with a detached writeState backing store does not crash [28.00ms]
(pass) zlib native handle driven outside the zlib.ts lifecycle > zlib: init() after close() throws [76.47ms]
(pass) zlib native handle driven outside the zlib.ts lifecycle > z
... (truncated)

passes on PR (with fix)

ASAN with fix: all passed
$ BUN_DEBUG_QUIET_LOGS=1 bun scripts/build.ts --profile=debug --quiet test "--reporter=junit" "--reporter-outfile=/tmp/pr_gate.xml" test/js/node/zlib/zlib-handle-bounds-check.test.ts
bun test v1.4.3 (367d939d9)

test/js/node/zlib/zlib-handle-bounds-check.test.ts:
(pass) zlib native handle bounds checking > writeSync rejects in_len exceeding input buffer [124.19ms]
(pass) zlib native handle bounds checking > writeSync rejects out_len exceeding output buffer [10.25ms]
(pass) zlib native handle bounds checking > writeSync rejects in_off + in_len exceeding input buffer [7.33ms]
(pass) zlib native handle bounds checking > writeSync rejects out_off + out_len exceeding output buffer [7.18ms]
(pass) zlib native handle bounds checking > writeSync allows valid bounds [6.57ms]
(pass) zlib native handle bounds checking > writeSync allows valid offset + length within bounds [7.05ms]
(pass) zlib native handle bounds checking > writeSync allows null input (flush only) [6.22ms]
(pass) zlib native handle writeState > writeSync updates the writeState array [7.05ms]
(pass) zlib native handle writeState > write completion with a detached writeState backing store does not crash [827.42m
... (truncated)

release with fix: all passed
$ bun scripts/build.ts --profile=release
[configured] bun-profile → bun (stripped) in 7082ms (unchanged)
ninja: Entering directory `/workspace/bun/build/release'
[1/94] gen cpp.rs (cppbind)
[2/93] cxx obj/unified/UnifiedSource-src_jsc_bindings_webcore-2.cpp.o
[3/93] cxx obj/src/jsc/bindings/webcore/SerializedScriptValue.cpp.o
[4/93] gen generated_host_exports.rs
generated_host_exports.rs: 121 exports (host=5, lazy=10, generic=106, rust=0); 248 extern-C blocks audited
[5/92] rustc bun_platform 
[6/92] rustc bun_core 
[7/92] rustc bun_zlib_sys 
[8/92] rustc bun_safety 
[9/92] rustc bun_output 
[10/92] rustc bun_errno 
[11/92] rustc bun_base64 
[12/92] rustc bun_picohttp 
[13/92] rustc bun_ptr 
[14/92] rustc bun_zstd 
[15/92] rustc bun_brotli 
[16/92] rustc bun_boringssl_sys 
[17/92] rustc bun_cares_sys 
[18/92] rustc bun_clap 
[19/92] rustc bun_lsquic_sys 
[20/92] rustc bun_valkey 
[21/92] rustc bun_tcc_sys 
[22/92] rustc bun_shell_parser 
warning: `feature(generic_const_exprs)` is not supported with the next-generation trait solver
 --> src/shell_parser/lib.rs:1:30
  |
1 | #![feature(adt_const_params, generic_const_exprs, allocator_api)]
  |                        
... (truncated)

diff hotspot

.../zstd/free-workers-before-dictionaries.patch    |  37 +++++++
 scripts/build/deps/zstd.ts                         |  14 ++-
 scripts/build/workarounds.ts                       |  23 +++++
 src/runtime/node/zlib/NativeZstd.rs                |  25 +----
 src/zstd/lib.rs                                    |   1 -
 test/js/node/zlib/zlib-handle-bounds-check.test.ts | 115 +++++++++++++++++++++
 6 files changed, 188 insertions(+), 27 deletions(-)

gate history · 1 passed · 0 rejected · iteration 0

evidence per changed file

file                                                 reads  edits  tests
patches/zstd/free-workers-before-dictionaries.patch      0      1     45
scripts/build/deps/zstd.ts                               3      4     48
scripts/build/workarounds.ts                             1      1     46
src/runtime/node/zlib/NativeZstd.rs                      4      4     46
src/zstd/lib.rs                                          1      1     47
test/js/node/zlib/zlib-handle-bounds-check.test.ts       4      2     45

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Walkthrough

The zstd cleanup path now joins worker threads before freeing dictionaries. Context::close no longer resets the context before freeing it. Subprocess tests cover worker jobs during stream cleanup and verify completed-frame decompression.

Changes

Zstd context cleanup

Layer / File(s)	Summary
Join workers before freeing dictionaries patches/zstd/free-workers-before-dictionaries.patch, scripts/build/deps/zstd.ts, scripts/build/workarounds.ts	The zstd patch changes context cleanup to join worker threads before clearing dictionaries. The dependency configuration applies the patch after bmi2-probe-once.patch. The workaround registry checks the pinned zstd commit and provides cleanup instructions.
Update close handling and cover worker jobs src/runtime/node/zlib/NativeZstd.rs, src/zstd/lib.rs, test/js/node/zlib/zlib-handle-bounds-check.test.ts	Context::close no longer resets the context before freeing existing state. The ZSTD_CCtx_reset FFI declaration is removed. Subprocess tests cover stream destruction, close, reinitialization, reset, zero-byte jobs, and completed-frame decompression.

Suggested reviewers: jarred-sumner

Priority: ⬆️ High

Severity of issue fixed: Medium

Merge Risk: ⚪ Minimal · up to 781d5

This change orders worker shutdown before dictionary release and adds regression coverage for teardown paths. No concrete unresolved merge risk was found; it is ready for normal checks.

🚥 Pre-merge checks | ✅ 4

✅ Passed checks (4 passed)

Check name	Status	Explanation
Linked Issues check	✅ Passed	The PR satisfies the coding requirements in #44201. free-workers-before-dictionaries.patch moves ZSTDMT_freeCCtx() before ZSTD_clearAllDicts(), so zstd joins workers before it frees dictionaries…
Out of Scope Changes check	✅ Passed	The changed files remain connected to #44201. The zstd patch fixes the reported cleanup order. NativeZstd.rs removes the unsafe reset path. The dependency registration applies the patch. The tests e…
Title check	✅ Passed	The title clearly and concisely describes the primary change: freeing zstd worker threads before the dictionaries they read.
Description check	✅ Passed	The description clearly explains the problem, fix, scope, downsides, verification steps, test results, and remaining issues. It uses Problem and Fix headings instead of the template headings, but it c…

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Actionable comments posted: 1

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Inline comments:
Review comments at @src/runtime/node/zlib/NativeZstd.rs:
- Around line 648-649: Remove the two comments about skipping reset before
freeing from the close logic in NativeZstd; keep the `is_some()` guard and its
existing explanation unchanged.

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📒 Files selected for processing (4)

• patches/zstd/free-workers-before-dictionaries.patch
• scripts/build/deps/zstd.ts
• src/runtime/node/zlib/NativeZstd.rs
• test/js/node/zlib/zlib-handle-bounds-check.test.ts

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[claude]

Nothing blocking. The comments below are optional suggestions. There is no need to push a fix for them before merging.

Beyond the inline findings, I also checked the other paths that free a CCtx with a dictionary: the second _handle.init() goes through deinit_state -> ZSTD_freeCCtx (now joins before ZSTD_clearAllDicts via the patch), and the two ZSTD_freeCCtx sites in src/runtime/webcore/CompressionStreamCoder.rs never set nbWorkers, so neither is affected. Dropping the ZSTD_DCtx_reset in Context::close is behavior-preserving since ZSTD_freeDCtx releases the same state; ZSTD_CCtx_loadDictionary is only called on a freshly created context in init.

Extended reasoning...

The change adds a vendored zstd source patch that moves ZSTD_clearAllDicts after ZSTDMT_freeCCtx in ZSTD_freeCCtxContent, registers it in scripts/build/deps/zstd.ts, removes the pre-free ZSTD_CCtx_reset/ZSTD_DCtx_reset calls from Context::close in src/runtime/node/zlib/NativeZstd.rs, and appends seven serial subprocess tests. It touches no auth, crypto, or input-parsing surface; the sensitive surface is native memory lifetime across zstd worker threads. Verified findings exist (one on the serial test's wall time, one on the now-dead ZSTD_CCtx_reset extern), and a vendored-dependency patch warrants a maintainer look, so this is not an approve.

[robobun]

Status: ready for review. The diff is green. The red CI jobs are red by tests that this diff does not touch.

CI.

• Build 122713 (c757cc66e0): 181 of 181 jobs passed. The commits after it change only files under scripts/build/.
• Build 122785 (781d5d227c): 180 of 181. The red job is debian 13 x64-asan - test-bun, by test/js/bun/spawn/spawn.test.ts ("an idle reader stopped at the highwater mark"). That test is red on main too, and spawn: restart syscalls interrupted by the waiter thread's SIGCHLD handler #43646 has its fix.
• Build 122825 (3b10e05fd0, an empty commit on top): 179 of 181. The same job is red again, by the same test. The second red job is darwin any x64 - test-bun, by test/js/web/workers/worker-terminate-lifetime.test.ts ("worker exit with streaming-request-body fetches whose response.body was touched"). That test was red on other PRs on that lane today (Buildkite 122818), and test(worker-terminate-lifetime): exit the fetch-teardown fixture on its condition, not on a clock #40781 is the open PR for it.
• I do not push again for CI. The PR waits for a maintainer.

State on 2026-10-19. main (c1df64b8d5) still has the bug: Context::close (src/runtime/node/zlib/NativeZstd.rs:645) resets the context and then frees it, and the zstd pin and its patch list are unchanged. This branch is 167 commits behind main and merges with no conflict (git merge-tree). Since the merge base, main changed one file of this diff, src/zstd/lib.rs (new decompression helpers, in other lines).

How it reproduces. Save this as repro.cjs and run it with a released bun:

const zlib = require("node:zlib");
const { pbkdf2Sync } = require("node:crypto");
const C = zlib.constants;
const hex = (seed, length) => Buffer.from(pbkdf2Sync(seed, "", 1, length / 2, "sha256").toString("hex"));
const dictionary = hex("dictionary", 192 * 1024);
const input = hex("input", 512 * 1024);
const params = {
  [C.ZSTD_c_nbWorkers]: 2,
  [C.ZSTD_c_jobSize]: input.length,
  [C.ZSTD_c_overlapLog]: 1,
  [C.ZSTD_c_compressionLevel]: 19,
};
const stream = zlib.createZstdCompress({ dictionary, params }).on("data", () => {});
stream.write(input, () => {
  stream.destroy(); // a worker still compresses the chunk
  console.log("destroyed");
});

• bun 1.4.3-canary.1+367d939d9 (release, linux x64): segmentation fault, exit code 139, 5 of 5 runs.
• Node v26.3.0: segmentation fault, 3 of 3 runs.
• This branch: prints destroyed, exit code 0. It is the destroy() row of the new tests.

With the tests: bun bd test test/js/node/zlib/zlib-handle-bounds-check.test.ts -t "zstd: a compressor with workers and a dictionary". A debug + ASAN build of main fails 6 of the 7 rows (heap-use-after-free). This branch passes 7.

[claude]

Nothing blocking. The comments below are optional suggestions. There is no need to push a fix for them before merging.

Still open from earlier reviews (2):

• Unresolved: 2 minor or pre-existing.

[claude]

Code review found no issues

No high-confidence issues detected in this change.

Still open from earlier reviews (1):

• Unresolved: 1 minor or pre-existing.

[robobun]

^{Updated 5:01 AM PT - Oct 2nd, 2026}

❌ @robobun, your commit 3b10e05 has 2 failures in Build #122825 (All Failures):

• test/js/web/workers/worker-terminate-lifetime.test.ts - code 1 on 🍎 any x64
• test/js/bun/spawn/spawn.test.ts - code 1: stdout reader of an unref'd child and process lifetime > an idle reader stopped at the highwater … on 🐧 13 x64-asan

---

🧪   To try this PR locally:

bunx bun-pr 44421

That installs a local version of the PR into your bun-44421 executable, so you can run:

bun-44421 --bun

[claude]

I reviewed the latest push and found no bugs; the last commit keeps the const ZSTD_COMMIT = ... line as the update-zstd workflow's sed expects it and reads the pin through zstd.source(cfg) instead. Because this reorders teardown inside vendored zstd under multithreading and adds a serial subprocess block whose wall time on the debug lane is a maintainer call, a human look would still be worthwhile.

What was reviewed:

• The patch hunk: ZSTDMT_freeCCtx only frees its own cdictLocal, so clearing the CCtx dictionaries after the join leaves nothing dangling; the patch format matches bmi2-probe-once.patch for git apply.
• Context::close now mirrors NativeBrotli::close (free via deinit_state, then mode = NONE); init's error paths and reset -> init still reach ZSTD_freeCCtx, which joins first with the patch; ZSTD_CCtx_reset extern has no remaining caller.
• workarounds.ts importing deps/zstd.ts creates no import cycle (zstd.ts imports only types), and expectedToBeFixed is typed as (cfg) => boolean as the interface requires.

Extended reasoning...

The change touches a vendored zstd C source via a new patch (reordering ZSTD_clearAllDicts after ZSTDMT_freeCCtx in ZSTD_freeCCtxContent), the node:zlib zstd Context::close in src/runtime/node/zlib/NativeZstd.rs, the zstd FFI declarations, the build workaround registry, and a new serial describe block of seven subprocess tests. It touches no auth, crypto, injection, or data-exposure surface; the security-relevant aspect is a heap-use-after-free fix in native multithreaded teardown. All three earlier findings from this bot (dead extern, missing workaround entry, exported pin breaking the update workflow) are addressed by commits c757cc6, bd42e3f and 781d5d2. Defer rather than approve because the fix is in vendored C threading/teardown code where correctness depends on zstd internals I cannot fully trace from this checkout, and the test block's serial runtime against the 10s/file budget is a judgment call the author self-resolved.

[Jarred-Sumner]

This is Claude (an AI assistant) commenting on Jarred's behalf.

This fix went in with #46021, which is merged. Closing.