Hacktoberfest 2026：维护者为十月标记出来的 issue，仍然开放、适合新手。 浏览 Hacktoberfest issue

SIGSEGV in libmsodbcsql during process teardown (iconv_close) on macOS arm64 with concurrent encrypted connections

未关闭
  • 哪里不对？
#685 2 条评论 0 个 reaction 已指派 1 人 在 GitHub 查看

维护者通常 2 天内回复

@bewithgaurav 已经在做这个了。

开始于 2026年7月20日。

评估

这个 Issue 还没有评估数据。

描述

area: packaging-platform bug dependency: external triage done

Summary

On macOS arm64, the process crashes with SIGSEGV during interpreter/process teardown (exit() → __cxa_finalize_ranges), inside the driver's static destructor calling iconv_close. The crash surfaces at shutdown when multiple worker threads have been using encrypted connections (Encrypt=yes) concurrently. The process terminates with exit code 139 and no Python traceback.

This appears related to, but distinct from, #668 (TLS stream corruption on concurrent encrypted reads — data corruption, no crash) and #679 (SIGSEGV in SQLFetchScroll during concurrent fetchmany). Here the faulting frame is not SQLFetchScroll but the driver's teardown path via libiconv.

Environment

  • macOS 26.5.2 (build 25F84), Apple Silicon (arm64)
  • Python 3.12.11
  • mssql-python 1.11.0 (bundled libmsodbcsql.18.dylib, mssql_python/libs/macos/arm64)
  • SQLAlchemy 2.1.0b3
  • Connection options: Encrypt=yes, TrustServerCertificate=yes, SNAPSHOT isolation
  • Concurrency: multiple worker threads. mssql-python's native connection pooling is enabled (enable_pooling=True), which uses a process-global pooling manager, so encrypted connections are pooled and reused across the process rather than being one-per-thread.

Crash

Signal: SIGSEGV / EXC_BAD_ACCESS (KERN_INVALID_ADDRESS), subtype "possible pointer authentication failure" at a wild address.

Faulting thread (from the macOS .ips crash report):

libiconv.2.dylib       _citrus_iconv_close
libiconv.2.dylib       __bsd_iconv_close
libmsodbcsql.18.dylib  <driver frame>
libsystem_c.dylib      __cxa_finalize_ranges
libsystem_c.dylib      exit
libdyld.dylib          dyld4::LibSystemHelpers::exit(int) const
dyld                   dyld4::LibSystemHelpersWrapper::exit(int) const
dyld                   start

So the crash happens while the process is exiting: exit() runs C++ static destructors (__cxa_finalize_ranges), one of which belongs to libmsodbcsql.18.dylib and calls iconv_close on what looks like an already-freed or corrupted iconv handle, producing a pointer-authentication failure.

Scenario

  1. Several worker threads read from different tables concurrently under SNAPSHOT isolation over pooled encrypted connections (Encrypt=yes).
  2. The application begins shutting down (an unrelated application-level error triggers a fail-fast exit()) while those threads/connections are still being torn down.
  3. During exit(), the driver's static-destructor cleanup segfaults in iconv_close.

The iconv involvement is notable: iconv is the character-encoding conversion layer, and #668 reports TLS/stream corruption specifically under concurrent encrypted reads on arm64. A corrupted iconv handle that only faults at driver finalization is consistent with encoding/stream state being left in a bad state under that same concurrency.

Relation to existing issues

  • #668 — TLS stream corruption on concurrent encrypted reads (arm64): data corruption / protocol errors, no hard crash.
  • #679 — SIGSEGV in SQLFetchScroll during concurrent fetchmany (arm64).

This report is a third manifestation on the same platform and connection profile (macOS arm64, Encrypt=yes, concurrent threaded reads), but the crash occurs at process teardown via libiconv, not during an active fetch. Filing separately so the teardown/iconv stack is tracked; it may share the root cause reported in #668.

Notes

  • No Python-level exception is raised for the crash itself; only the exit code (139) and the macOS crash report indicate it.
主要语言
Python
星标
478
派生
62
平均合并
3 天 1 小时
30 天内合并 PR
26

环境准备

在 Codespaces 中打开

在浏览器里用你自己的 GitHub 账号启动这个项目的开发容器。

从这里开始

  1. 先读完整个 Issue，再读项目的贡献指南。
  2. 在 Issue 下留言说明你要接手 —— 这能避免两个人做同样的事。
  3. Fork 仓库，在一个分支上完成修改。
  4. 提交 Pull Request，并在描述里引用这个 Issue 编号。

microsoft/mssql-python 的其他 Issue

查看 microsoft/mssql-python 的全部 Issue

相似的 Issue

更多 Python Issue

把新 issue 发到你的邮箱

精选适合新手参与的 GitHub issue 摘要。