From 8d07b7deffbddac47e9ad5f422f0bf3c2690e748 Mon Sep 17 00:00:00 2001
From: David Chisnall <theraven@FreeBSD.org>
Date: Wed, 2 Apr 2014 11:10:46 +0000
Subject: [PATCH] Fix an issue where the locale and rune locale could become
 out of sync, causing mb* functions (and similar) to be called with the wrong
 data (possibly a null pointer, causing a crash).

PR:		standards/188036
MFC after:	1 week
---
 lib/libc/locale/setrunelocale.c |  2 ++
 lib/libc/locale/xlocale.c       | 16 +++++++---------
 2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/lib/libc/locale/setrunelocale.c b/lib/libc/locale/setrunelocale.c
index 49e6f6e6548b..0a0943febb45 100644
--- a/lib/libc/locale/setrunelocale.c
+++ b/lib/libc/locale/setrunelocale.c
@@ -202,6 +202,8 @@ __set_thread_rune_locale(locale_t loc)
 
 	if (loc == NULL) {
 		_ThreadRuneLocale = &_DefaultRuneLocale;
+	} else if (loc == LC_GLOBAL_LOCALE) {
+		_ThreadRuneLocale = 0;
 	} else {
 		_ThreadRuneLocale = XLOCALE_CTYPE(loc)->runes;
 	}
diff --git a/lib/libc/locale/xlocale.c b/lib/libc/locale/xlocale.c
index e114bac74f2c..f9b7db107aec 100644
--- a/lib/libc/locale/xlocale.c
+++ b/lib/libc/locale/xlocale.c
@@ -154,23 +154,24 @@ __get_locale(void)
 static void
 set_thread_locale(locale_t loc)
 {
+	locale_t l = (loc == LC_GLOBAL_LOCALE) ? 0 : loc;
 
 	_once(&once_control, init_key);
 	
-	if (NULL != loc) {
-		xlocale_retain((struct xlocale_refcounted*)loc);
+	if (NULL != l) {
+		xlocale_retain((struct xlocale_refcounted*)l);
 	}
 	locale_t old = pthread_getspecific(locale_info_key);
-	if ((NULL != old) && (loc != old)) {
+	if ((NULL != old) && (l != old)) {
 		xlocale_release((struct xlocale_refcounted*)old);
 	}
 	if (fake_tls) {
-		thread_local_locale = loc;
+		thread_local_locale = l;
 	} else {
-		pthread_setspecific(locale_info_key, loc);
+		pthread_setspecific(locale_info_key, l);
 	}
 #ifndef __NO_TLS
-	__thread_locale = loc;
+	__thread_locale = l;
 	__set_thread_rune_locale(loc);
 #endif
 }
@@ -361,9 +362,6 @@ locale_t uselocale(locale_t loc)
 {
 	locale_t old = get_thread_locale();
 	if (NULL != loc) {
-		if (LC_GLOBAL_LOCALE == loc) {
-			loc = NULL;
-		}
 		set_thread_locale(loc);
 	}
 	return (old ? old : LC_GLOBAL_LOCALE);