From b4b5c2188f9d574b8ddb05355d030f530b165cb2 Mon Sep 17 00:00:00 2001
From: Tanner Bruce <tanner@tanners.space>
Date: Thu, 8 Oct 2015 21:44:38 -0500
Subject: [PATCH] Check that $XDG_RUNTIME_DIR is valid and accessible

Signed-off-by: David Adam <zanchey@ucc.gu.uwa.edu.au>
---
 src/env_universal_common.cpp | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/env_universal_common.cpp b/src/env_universal_common.cpp
index d5d14378a..c67fa4150 100644
--- a/src/env_universal_common.cpp
+++ b/src/env_universal_common.cpp
@@ -147,7 +147,12 @@ static wcstring get_runtime_path()
 {
     wcstring result;
     const char *dir = getenv("XDG_RUNTIME_DIR");
-    if (dir != NULL)
+
+    // Check that the path is actually usable
+    // Technically this is guaranteed by the fdo spec but in practice
+    // it is not always the case: see #1828 and #2222
+    int mode = R_OK | W_OK | X_OK;
+    if (dir != NULL && access(dir, mode) == 0 && check_runtime_path(dir) == 0)
     {
         result = str2wcstring(dir);
     }