diff -Nur samba-4.18.6/nsswitch/libwbclient/wscript samba-4.18.6-fix-winbind/nsswitch/libwbclient/wscript
--- samba-4.18.6/nsswitch/libwbclient/wscript	2023-09-02 13:38:31.262884402 -0700
+++ samba-4.18.6-fix-winbind/nsswitch/libwbclient/wscript	2023-09-02 13:37:58.293056486 -0700
@@ -27,13 +27,9 @@
 #
 #    Logs.info("\tSelected embedded libwbclient build")
 
-    wbclient_internal_deps = 'replace'
-    if bld.CONFIG_SET('HAVE_PTHREAD'):
-        wbclient_internal_deps += ' pthread'
-
     bld.SAMBA_SUBSYSTEM('wbclient-internal',
         source='../wb_common.c',
-        deps=wbclient_internal_deps,
+        deps='replace',
         cflags='-DWINBINDD_SOCKET_DIR=\"%s\"' % bld.env.WINBINDD_SOCKET_DIR,
         hide_symbols=True,
         provide_builtin_linking=True,
diff -Nur samba-4.18.6/nsswitch/wb_common.c samba-4.18.6-fix-winbind/nsswitch/wb_common.c
--- samba-4.18.6/nsswitch/wb_common.c	2023-09-02 13:38:34.506064173 -0700
+++ samba-4.18.6-fix-winbind/nsswitch/wb_common.c	2023-09-02 13:37:58.293056486 -0700
@@ -26,7 +26,6 @@
 #include "replace.h"
 #include "system/select.h"
 #include "winbind_client.h"
-#include <assert.h>
 
 #ifdef HAVE_PTHREAD_H
 #include <pthread.h>
@@ -42,123 +41,30 @@
 	pid_t our_pid;		/* calling process pid */
 };
 
-static struct wb_global_ctx {
-	bool initialized;
 #ifdef HAVE_PTHREAD
-	pthread_once_t control;
-	pthread_key_t key;
-#else
-	bool dummy;
-#endif
-} wb_global_ctx = {
-#ifdef HAVE_PTHREAD
-	.control = PTHREAD_ONCE_INIT,
-#endif
-};
-
-static void winbind_close_sock(struct winbindd_context *ctx);
-
-#ifdef HAVE_PTHREAD
-static void wb_thread_ctx_initialize(void);
-
-static void wb_atfork_child(void)
-{
-	struct winbindd_context *ctx = NULL;
-	int ret;
-
-	ctx = (struct winbindd_context *)pthread_getspecific(wb_global_ctx.key);
-	if (ctx == NULL) {
-		return;
-	}
-
-	ret = pthread_setspecific(wb_global_ctx.key, NULL);
-	assert(ret == 0);
-
-	winbind_close_sock(ctx);
-	free(ctx);
-
-	ret = pthread_key_delete(wb_global_ctx.key);
-	assert(ret == 0);
-
-	wb_global_ctx.control = (pthread_once_t)PTHREAD_ONCE_INIT;
-}
-
-static void wb_thread_ctx_destructor(void *p)
-{
-	struct winbindd_context *ctx = (struct winbindd_context *)p;
-
-	winbind_close_sock(ctx);
-	free(ctx);
-}
-
-static void wb_thread_ctx_initialize(void)
-{
-	int ret;
-
-	ret = pthread_atfork(NULL,
-			     NULL,
-			     wb_atfork_child);
-	assert(ret == 0);
-
-	ret = pthread_key_create(&wb_global_ctx.key,
-				 wb_thread_ctx_destructor);
-	assert(ret == 0);
-}
+static pthread_mutex_t wb_global_ctx_mutex = PTHREAD_MUTEX_INITIALIZER;
 #endif
 
-static struct winbindd_context *get_wb_thread_ctx(void)
+static struct winbindd_context *get_wb_global_ctx(void)
 {
-	struct winbindd_context *ctx = NULL;
-	int ret;
-
-	ret = pthread_once(&wb_global_ctx.control,
-			   wb_thread_ctx_initialize);
-	assert(ret == 0);
-
-	ctx = (struct winbindd_context *)pthread_getspecific(
-		wb_global_ctx.key);
-	if (ctx != NULL) {
-		return ctx;
-	}
-
-	ctx = malloc(sizeof(struct winbindd_context));
-	if (ctx == NULL) {
-		return NULL;
-	}
-
-	*ctx = (struct winbindd_context) {
+	static struct winbindd_context wb_global_ctx = {
 		.winbindd_fd = -1,
 		.is_privileged = false,
 		.our_pid = 0
 	};
 
-	ret = pthread_setspecific(wb_global_ctx.key, ctx);
-	if (ret != 0) {
-		free(ctx);
-		return NULL;
-	}
-	return ctx;
+#ifdef HAVE_PTHREAD
+	pthread_mutex_lock(&wb_global_ctx_mutex);
+#endif
+	return &wb_global_ctx;
 }
 
-static struct winbindd_context *get_wb_global_ctx(void)
+static void put_wb_global_ctx(void)
 {
-	struct winbindd_context *ctx = NULL;
-#ifndef HAVE_PTHREAD
-	static struct winbindd_context _ctx = {
-		.winbindd_fd = -1,
-		.is_privileged = false,
-		.our_pid = 0
-	};
-#endif
-
 #ifdef HAVE_PTHREAD
-	ctx = get_wb_thread_ctx();
-#else
-	ctx = &_ctx;
+	pthread_mutex_unlock(&wb_global_ctx_mutex);
 #endif
-
-	wb_global_ctx.initialized = true;
-	return ctx;
+	return;
 }
 
 void winbind_set_client_name(const char *name)
@@ -242,20 +148,9 @@
 {
 	struct winbindd_context *ctx;
 
-	if (!wb_global_ctx.initialized) {
-		return;
-	}
-
-#ifdef HAVE_PTHREAD_H
-	ctx = (struct winbindd_context *)pthread_getspecific(wb_global_ctx.key);
-	if (ctx == NULL) {
-		return;
-	}
-#else
 	ctx = get_wb_global_ctx();
-#endif
-
 	winbind_close_sock(ctx);
+	put_wb_global_ctx();
 }
 
 #define CONNECT_TIMEOUT 30
@@ -887,9 +782,11 @@
 				     struct winbindd_response *response)
 {
 	NSS_STATUS status = NSS_STATUS_UNAVAIL;
+	bool release_global_ctx = false;
 
 	if (ctx == NULL) {
 		ctx = get_wb_global_ctx();
+		release_global_ctx = true;
 	}
 
 	status = winbindd_send_request(ctx, req_type, 0, request);
@@ -899,6 +796,9 @@
 	status = winbindd_get_response(ctx, response);
 
 out:
+	if (release_global_ctx) {
+		put_wb_global_ctx();
+	}
 	return status;
 }
 
@@ -908,9 +808,11 @@
 					  struct winbindd_response *response)
 {
 	NSS_STATUS status = NSS_STATUS_UNAVAIL;
+	bool release_global_ctx = false;
 
 	if (ctx == NULL) {
 		ctx = get_wb_global_ctx();
+		release_global_ctx = true;
 	}
 
 	status = winbindd_send_request(ctx, req_type, 1, request);
@@ -920,6 +822,9 @@
 	status = winbindd_get_response(ctx, response);
 
 out:
+	if (release_global_ctx) {
+		put_wb_global_ctx();
+	}
 	return status;
 }