From 51416738eae1ab5c16cbaa97a4293dbc8c809b79 Mon Sep 17 00:00:00 2001
From: Simon Ser <contact@emersion.fr>
Date: Tue, 22 Oct 2019 23:43:15 +0200
Subject: [PATCH] render/egl: prevent use-after-free when destroying current
 surface

---
 render/egl.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/render/egl.c b/render/egl.c
index 69fde225c..cbd92cb9e 100644
--- a/render/egl.c
+++ b/render/egl.c
@@ -646,5 +646,12 @@ bool wlr_egl_destroy_surface(struct wlr_egl *egl, EGLSurface surface) {
 	if (!surface) {
 		return true;
 	}
+	if (eglGetCurrentContext() == egl->context &&
+			eglGetCurrentSurface(EGL_DRAW) == surface) {
+		// Reset the current EGL surface in case it's the one we're destroying,
+		// otherwise the next wlr_egl_make_current call will result in a
+		// use-after-free.
+		wlr_egl_make_current(egl, NULL, NULL);
+	}
 	return eglDestroySurface(egl->display, surface);
 }