diff --git a/client/Wayland/wlfreerdp.c b/client/Wayland/wlfreerdp.c
index 5086220d2..11b747e60 100644
--- a/client/Wayland/wlfreerdp.c
+++ b/client/Wayland/wlfreerdp.c
@@ -62,6 +62,7 @@ static BOOL wl_begin_paint(rdpContext* context)
 
 static BOOL wl_update_buffer(wlfContext* context_w, INT32 ix, INT32 iy, INT32 iw, INT32 ih)
 {
+	BOOL res = FALSE;
 	rdpGdi* gdi;
 	char* data;
 	UINT32 x, y, w, h;
@@ -76,6 +77,7 @@ static BOOL wl_update_buffer(wlfContext* context_w, INT32 ix, INT32 iy, INT32 iw
 	if ((ix < 0) || (iy < 0) || (iw < 0) || (ih < 0))
 		return FALSE;
 
+	EnterCriticalSection(&context_w->critical);
 	x = (UINT32)ix;
 	y = (UINT32)iy;
 	w = (UINT32)iw;
@@ -84,16 +86,19 @@ static BOOL wl_update_buffer(wlfContext* context_w, INT32 ix, INT32 iy, INT32 iw
 	data = UwacWindowGetDrawingBuffer(context_w->window);
 
 	if (!data || (rc != UWAC_SUCCESS))
-		return FALSE;
+		goto fail;
 
 	gdi = context_w->context.gdi;
 
 	if (!gdi)
-		return FALSE;
+		goto fail;
 
 	/* Ignore output if the surface size does not match. */
 	if (((INT64)x > geometry.width) || ((INT64)y > geometry.height))
-		return TRUE;
+	{
+		res = TRUE;
+		goto fail;
+	}
 
 	area.left = x;
 	area.top = y;
@@ -103,21 +108,24 @@ static BOOL wl_update_buffer(wlfContext* context_w, INT32 ix, INT32 iy, INT32 iw
 	if (!wlf_copy_image(gdi->primary_buffer, gdi->stride, gdi->width, gdi->height, data, stride,
 	                    geometry.width, geometry.height, &area,
 	                    context_w->context.settings->SmartSizing))
-		return FALSE;
+		goto fail;
 
 	if (!wlf_scale_coordinates(&context_w->context, &x, &y, FALSE))
-		return FALSE;
+		goto fail;
 
 	if (!wlf_scale_coordinates(&context_w->context, &w, &h, FALSE))
-		return FALSE;
+		goto fail;
 
 	if (UwacWindowAddDamage(context_w->window, x, y, w, h) != UWAC_SUCCESS)
-		return FALSE;
+		goto fail;
 
 	if (UwacWindowSubmitBuffer(context_w->window, false) != UWAC_SUCCESS)
-		return FALSE;
+		goto fail;
 
-	return TRUE;
+	res = TRUE;
+fail:
+	LeaveCriticalSection(&context_w->critical);
+	return res;
 }
 
 static BOOL wl_end_paint(rdpContext* context)
@@ -296,6 +304,7 @@ static void wl_post_disconnect(freerdp* instance)
 
 static BOOL handle_uwac_events(freerdp* instance, UwacDisplay* display)
 {
+	BOOL rc;
 	UwacEvent event;
 	wlfContext* context;
 
@@ -321,9 +330,11 @@ static BOOL handle_uwac_events(freerdp* instance, UwacDisplay* display)
 				break;
 
 			case UWAC_EVENT_FRAME_DONE:
-				if (UwacWindowSubmitBuffer(context->window, false) != UWAC_SUCCESS)
+				EnterCriticalSection(&context->critical);
+				rc = UwacWindowSubmitBuffer(context->window, false);
+				LeaveCriticalSection(&context->critical);
+				if (rc != UWAC_SUCCESS)
 					return FALSE;
-
 				break;
 
 			case UWAC_EVENT_POINTER_ENTER:
@@ -552,6 +563,8 @@ static BOOL wlf_client_new(freerdp* instance, rdpContext* context)
 	if (!wfl->displayHandle)
 		return FALSE;
 
+	InitializeCriticalSection(&wfl->critical);
+
 	return TRUE;
 }
 
@@ -567,6 +580,7 @@ static void wlf_client_free(freerdp* instance, rdpContext* context)
 
 	if (wlf->displayHandle)
 		CloseHandle(wlf->displayHandle);
+	DeleteCriticalSection(&wlf->critical);
 }
 
 static int wfl_client_start(rdpContext* context)
diff --git a/client/Wayland/wlfreerdp.h b/client/Wayland/wlfreerdp.h
index 09d056ae4..d64706690 100644
--- a/client/Wayland/wlfreerdp.h
+++ b/client/Wayland/wlfreerdp.h
@@ -50,6 +50,7 @@ struct wlf_context
 	wfClipboard* clipboard;
 	wlfDispContext* disp;
 	wLog* log;
+	CRITICAL_SECTION critical;
 };
 
 BOOL wlf_scale_coordinates(rdpContext* context, UINT32* px, UINT32* py, BOOL fromLocalToRDP);
diff --git a/uwac/libuwac/uwac-priv.h b/uwac/libuwac/uwac-priv.h
index 75ad6e0fe..2ef073de1 100644
--- a/uwac/libuwac/uwac-priv.h
+++ b/uwac/libuwac/uwac-priv.h
@@ -235,7 +235,8 @@ struct uwac_window
 
 	struct wl_region* opaque_region;
 	struct wl_region* input_region;
-	UwacBuffer *drawingBuffer, *pendingBuffer;
+	SSIZE_T drawingBufferIdx;
+	SSIZE_T pendingBufferIdx;
 	struct wl_surface* surface;
 	struct wl_shell_surface* shell_surface;
 	struct xdg_surface* xdg_surface;
diff --git a/uwac/libuwac/uwac-window.c b/uwac/libuwac/uwac-window.c
index f76d43bcc..1dc5574ff 100644
--- a/uwac/libuwac/uwac-window.c
+++ b/uwac/libuwac/uwac-window.c
@@ -136,13 +136,13 @@ static void xdg_handle_toplevel_configure(void* data, struct xdg_toplevel* xdg_t
 		{
 			assert(
 			    uwacErrorHandler(window->display, ret, "failed to reallocate a wayland buffers\n"));
-			window->drawingBuffer = window->pendingBuffer = NULL;
+			window->drawingBufferIdx = window->pendingBufferIdx = -1;
 			return;
 		}
 
-		window->drawingBuffer = &window->buffers[0];
-		if (window->pendingBuffer != NULL)
-			window->pendingBuffer = window->drawingBuffer;
+		window->drawingBufferIdx = 0;
+		if (window->pendingBufferIdx != -1)
+			window->pendingBufferIdx = window->drawingBufferIdx;
 	}
 	else
 	{
@@ -219,13 +219,13 @@ static void ivi_handle_configure(void* data, struct ivi_surface* surface, int32_
 		{
 			assert(
 			    uwacErrorHandler(window->display, ret, "failed to reallocate a wayland buffers\n"));
-			window->drawingBuffer = window->pendingBuffer = NULL;
+			window->drawingBufferIdx = window->pendingBufferIdx = -1;
 			return;
 		}
 
-		window->drawingBuffer = &window->buffers[0];
-		if (window->pendingBuffer != NULL)
-			window->pendingBuffer = window->drawingBuffer;
+		window->drawingBufferIdx = 0;
+		if (window->pendingBufferIdx != -1)
+			window->pendingBufferIdx = window->drawingBufferIdx;
 	}
 	else
 	{
@@ -277,13 +277,13 @@ static void shell_configure(void* data, struct wl_shell_surface* surface, uint32
 		{
 			assert(
 			    uwacErrorHandler(window->display, ret, "failed to reallocate a wayland buffers\n"));
-			window->drawingBuffer = window->pendingBuffer = NULL;
+			window->drawingBufferIdx = window->pendingBufferIdx = -1;
 			return;
 		}
 
-		window->drawingBuffer = &window->buffers[0];
-		if (window->pendingBuffer != NULL)
-			window->pendingBuffer = window->drawingBuffer;
+		window->drawingBufferIdx = 0;
+		if (window->pendingBufferIdx != -1)
+			window->pendingBufferIdx = window->drawingBufferIdx;
 	}
 	else
 	{
@@ -364,15 +364,21 @@ error_mmap:
 	return ret;
 }
 
-static UwacBuffer* UwacWindowFindFreeBuffer(UwacWindow* w)
+static UwacBuffer* UwacWindowFindFreeBuffer(UwacWindow* w, SSIZE_T* index)
 {
-	int i, ret;
+	SSIZE_T i;
+	int ret;
+
+	if (index)
+		*index = -1;
 
 	for (i = 0; i < w->nbuffers; i++)
 	{
 		if (!w->buffers[i].used)
 		{
 			w->buffers[i].used = true;
+			if (index)
+				*index = i;
 			return &w->buffers[i];
 		}
 	}
@@ -386,6 +392,8 @@ static UwacBuffer* UwacWindowFindFreeBuffer(UwacWindow* w)
 	}
 
 	w->buffers[i].used = true;
+	if (index)
+		*index = i;
 	return &w->buffers[i];
 }
 
@@ -457,7 +465,8 @@ UwacWindow* UwacCreateWindowShm(UwacDisplay* display, uint32_t width, uint32_t h
 	}
 
 	w->buffers[0].used = true;
-	w->drawingBuffer = &w->buffers[0];
+	w->drawingBufferIdx = 0;
+	w->pendingBufferIdx = -1;
 	w->surface = wl_compositor_create_surface(display->compositor);
 
 	if (!w->surface)
@@ -603,7 +612,16 @@ UwacReturnCode UwacWindowSetInputRegion(UwacWindow* window, uint32_t x, uint32_t
 
 void* UwacWindowGetDrawingBuffer(UwacWindow* window)
 {
-	return window->drawingBuffer->data;
+	UwacBuffer* buffer;
+
+	if (window->drawingBufferIdx < 0)
+		return NULL;
+
+	buffer = &window->buffers[window->drawingBufferIdx];
+	if (!buffer)
+		return NULL;
+
+	return buffer->data;
 }
 
 static void frame_done_cb(void* data, struct wl_callback* callback, uint32_t time);
@@ -654,7 +672,7 @@ static void frame_done_cb(void* data, struct wl_callback* callback, uint32_t tim
 	UwacFrameDoneEvent* event;
 
 	wl_callback_destroy(callback);
-	window->pendingBuffer = NULL;
+	window->pendingBufferIdx = -1;
 	event = (UwacFrameDoneEvent*)UwacDisplayNewEvent(window->display, UWAC_EVENT_FRAME_DONE);
 
 	if (event)
@@ -677,13 +695,20 @@ UwacReturnCode UwacWindowAddDamage(UwacWindow* window, uint32_t x, uint32_t y, u
                                    uint32_t height)
 {
 	RECTANGLE_16 box;
+	UwacBuffer* buf;
 
 	box.left = x;
 	box.top = y;
 	box.right = x + width;
 	box.bottom = y + height;
 
-	UwacBuffer* buf = window->drawingBuffer;
+	if (window->drawingBufferIdx < 0)
+		return UWAC_ERROR_INTERNAL;
+
+	buf = &window->buffers[window->drawingBufferIdx];
+	if (!buf)
+		return UWAC_ERROR_INTERNAL;
+
 	if (!region16_union_rect(&buf->damage, &buf->damage, &box))
 		return UWAC_ERROR_INTERNAL;
 
@@ -695,7 +720,7 @@ UwacReturnCode UwacWindowAddDamage(UwacWindow* window, uint32_t x, uint32_t y, u
 UwacReturnCode UwacWindowGetDrawingBufferGeometry(UwacWindow* window, UwacSize* geometry,
                                                   size_t* stride)
 {
-	if (!window || !window->drawingBuffer)
+	if (!window || (window->drawingBufferIdx < 0))
 		return UWAC_ERROR_INTERNAL;
 
 	if (geometry)
@@ -712,22 +737,29 @@ UwacReturnCode UwacWindowGetDrawingBufferGeometry(UwacWindow* window, UwacSize*
 
 UwacReturnCode UwacWindowSubmitBuffer(UwacWindow* window, bool copyContentForNextFrame)
 {
-	UwacBuffer* drawingBuffer = window->drawingBuffer;
+	UwacBuffer* currentDrawingBuffer;
+	UwacBuffer* nextDrawingBuffer;
+	UwacBuffer* pendingBuffer;
 
-	if (window->pendingBuffer || !drawingBuffer->dirty)
+	if (window->drawingBufferIdx < 0)
+		return UWAC_ERROR_INTERNAL;
+
+	currentDrawingBuffer = &window->buffers[window->drawingBufferIdx];
+
+	if ((window->pendingBufferIdx >= 0) || !currentDrawingBuffer->dirty)
 		return UWAC_SUCCESS;
 
-	window->pendingBuffer = drawingBuffer;
-	window->drawingBuffer = UwacWindowFindFreeBuffer(window);
+	window->pendingBufferIdx = window->drawingBufferIdx;
+	nextDrawingBuffer = UwacWindowFindFreeBuffer(window, &window->drawingBufferIdx);
+	pendingBuffer = &window->buffers[window->pendingBufferIdx];
 
-	if (!window->drawingBuffer)
+	if ((!nextDrawingBuffer) || (window->drawingBufferIdx < 0))
 		return UWAC_ERROR_NOMEMORY;
 
 	if (copyContentForNextFrame)
-		memcpy(window->drawingBuffer->data, window->pendingBuffer->data,
-		       window->stride * window->height);
+		memcpy(nextDrawingBuffer->data, pendingBuffer->data, window->stride * window->height);
 
-	UwacSubmitBufferPtr(window, drawingBuffer);
+	UwacSubmitBufferPtr(window, pendingBuffer);
 	return UWAC_SUCCESS;
 }