diff --git a/crypto/ec/ec_key.c b/crypto/ec/ec_key.c
index f01bf6b..480ed5f 100644
--- a/crypto/ec/ec_key.c
+++ b/crypto/ec/ec_key.c
@@ -374,6 +374,10 @@
 
   tx = BN_CTX_get(ctx);
   ty = BN_CTX_get(ctx);
+  if (tx == NULL ||
+      ty == NULL) {
+    goto err;
+  }
 
   if (!EC_POINT_set_affine_coordinates_GFp(key->group, point, x, y, ctx) ||
       !EC_POINT_get_affine_coordinates_GFp(key->group, point, tx, ty, ctx)) {