From 1b690e528fdea15c7290e015f3ec14fa03e69c6c Mon Sep 17 00:00:00 2001
From: rdb <git@rdb.name>
Date: Mon, 10 Jul 2017 21:10:47 +0200
Subject: [PATCH] vfs: don't crash if copy_file can't open output file (LP
 1687283)

---
 panda/src/express/virtualFileSimple.cxx | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/panda/src/express/virtualFileSimple.cxx b/panda/src/express/virtualFileSimple.cxx
index a036c0df4b..1c521b6459 100644
--- a/panda/src/express/virtualFileSimple.cxx
+++ b/panda/src/express/virtualFileSimple.cxx
@@ -150,7 +150,16 @@ copy_file(VirtualFile *new_file) {
   // Different mount point, or the mount doesn't support copying.  Do it by
   // hand.
   ostream *out = new_file->open_write_file(false, true);
+  if (out == nullptr) {
+    return false;
+  }
+
   istream *in = open_read_file(false);
+  if (in == nullptr) {
+    new_file->close_write_file(out);
+    new_file->delete_file();
+    return false;
+  }
 
   static const size_t buffer_size = 4096;
   char buffer[buffer_size];