[yosuke-wolfssl]

Problem

Three public wolfCrypt APIs lack some of argument checks:

• wolfAsync_DevOpenThread()
• wc_AsyncThreadCreate_ex()
• wc_SHE_ExportKey()

Fix (wolfcrypt/src/async.c, wolfcrypt/src/wc_she.c)

• wolfAsync_DevOpenThread() returns BAD_FUNC_ARG for a NULL pDevId before opening any device, and always writes the device ID.
• wc_AsyncThreadCreate_ex() returns BAD_FUNC_ARG for a NULL thread or function, before pthread_attr_init().
• wc_SHE_ExportKey() returns BAD_FUNC_ARG when a non-NULL Mn buffer is smaller than WC_SHE_Mn_SZ. The EN and JA doxygen list the new case.

NULL SHE buffers are still accepted, although f-12964 recommends rejecting them. The header and doxygen document NULL as "skip that message", and both in-tree test callbacks rely on it.

Closes f-9928, f-12969 and f-12964.

Tests

test_wc_SHE_CryptoCb checks each of M1-M5 one byte short (BAD_FUNC_ARG) and an all-NULL call (succeeds). The async changes have no new tests: they only add NULL checks, and the conditional write can only be reached with Cavium/QAT hardware.

Verification

• Builds clean with no compiler warnings under --enable-asynccrypt --enable-cryptocb --enable-debug, --enable-she=extended --enable-cryptocb --enable-debug, and with -DNO_WC_SHE_EXPORTKEY.
• testwolfcrypt passes on the async build; SHE API group 14/14 passes.
• Negative controls: removing the size check, comparing m2Sz against WC_SHE_M1_SZ, or dropping a mN != NULL guard each fails test_wc_SHE_CryptoCb.

[Copilot]

🟢 Approval recommended

No active review issues remain for the argument-validation changes.

No open issues 🎉

What changed in this PR

This PR hardens argument validation in three public wolfCrypt APIs while preserving the documented behavior that NULL SHE output buffers skip their messages.

Changes:

• Reject NULL arguments in the async device/thread APIs and always write the device ID when pDevId is valid.
• Reject undersized non-NULL SHE export buffers, with regression tests for M1–M5 and all-NULL outputs.
• Update English and Japanese API documentation for the new SHE error condition.

File	Description
wolfcrypt/​src/​wc_she.c	Validate SHE export buffer sizes.
wolfcrypt/​src/​async.c	Add NULL checks and make device-ID assignment unconditional.
tests/​api/​test_she.c	Test undersized buffers and accepted NULL outputs.
doc/​dox_comments/​header_files/​wc_she.h	Document the buffer-size error in English.
doc/​dox_comments/​header_files-ja/​wc_she.h	Document the buffer-size error in Japanese.

_{Review effort: Balanced}

[github-actions]

MemBrowse Memory Report · Explore what changed →

zephyr-frdm_rw612

• FLASH: log_const_area -8 B, rodata -8 B, text +1,592 B (+0.6%, 284,040 B / 67,108,864 B, total: 0% used)

No memory changes detected for:

• gcc-arm-cortex-m0plus
• gcc-arm-cortex-m3
• gcc-arm-cortex-m4
• gcc-arm-cortex-m4-baremetal
• gcc-arm-cortex-m4-crypto-only
• gcc-arm-cortex-m4-dtls13
• gcc-arm-cortex-m4-min-ecc
• gcc-arm-cortex-m4-openssl-compat
• gcc-arm-cortex-m4-pkcs7
• gcc-arm-cortex-m4-pq
• gcc-arm-cortex-m4-rsa-only
• gcc-arm-cortex-m4-sp-math
• gcc-arm-cortex-m4-tls12
• gcc-arm-cortex-m4-tls13
• gcc-arm-cortex-m7
• gcc-arm-cortex-m7-pq
• gcc-arm-cortex-m7-tls13
• stm32-sim-stm32h753

---

_{Catch memory regressions in CI with MemBrowse. Free for open source.}

[wolfSSL-Fenrir-bot]

Fenrir Automated Review — PR #12031

Scan targets checked: wolfcrypt-src, wolfcrypt-bugs, wolfssl-bugs
Not reviewed (no scan target covers them): doc/dox_comments/header_files-ja/wc_she.h, doc/dox_comments/header_files/wc_she.h
Coverage: 3 of 3 in-scope changed file(s) opened by the reviewer

Fenrir result: Approved ✅

No new issues found in the changed files.

Advisory only — this automated result does not count as a GitHub approval.

Review tier: Max