From 04a5d5b45d4e8cd8908574d7ce2b4b016bdf9694 Mon Sep 17 00:00:00 2001
From: guenther <>
Date: Tue, 7 Apr 2015 01:27:07 +0000
Subject: [PATCH] Make pthread_atfork() track the DSO that called it like
 atexit() does, unregistering callbacks if the DSO is unloaded.  Move the
 callback handling from libpthread to libc, though libpthread still overrides
 the inner call to handle locking and thread-library reinitialization. Major
 version bump for both libc and libpthread.

verification that this fixes various ports ajacoutot@
asm assistance miod@; ok millert@ deraadt@
---
 src/lib/libc/stdlib/atexit.c | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/src/lib/libc/stdlib/atexit.c b/src/lib/libc/stdlib/atexit.c
index 6532b382..a3308057 100644
--- a/src/lib/libc/stdlib/atexit.c
+++ b/src/lib/libc/stdlib/atexit.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: atexit.c,v 1.20 2014/07/11 09:51:37 kettenis Exp $ */
+/*	$OpenBSD: atexit.c,v 1.21 2015/04/07 01:27:07 guenther Exp $ */
 /*
  * Copyright (c) 2002 Daniel Hartmeier
  * All rights reserved.
@@ -35,6 +35,7 @@
 #include <string.h>
 #include <unistd.h>
 #include "atexit.h"
+#include "atfork.h"
 #include "thread_private.h"
 
 struct atexit *__atexit;
@@ -161,6 +162,23 @@ restart:
 		__atexit = NULL;
 	}
 	_ATEXIT_UNLOCK();
+
+	/*
+	 * If unloading a DSO, unregister any atfork handlers registered
+	 * by it.  Skip the locking if the list is currently empty.
+	 */
+	if (dso != NULL && TAILQ_FIRST(&_atfork_list) != NULL) {
+		struct atfork_fn *af, *afnext;
+
+		_ATFORK_LOCK();
+		TAILQ_FOREACH_SAFE(af, &_atfork_list, fn_next, afnext)
+			if (af->fn_dso == dso) {
+				TAILQ_REMOVE(&_atfork_list, af, fn_next);
+				free(af);
+			}
+		_ATFORK_UNLOCK();
+
+	}
 }
 
 /*