From 71a8239de5b65697304888a7044af13e32dc62f2 Mon Sep 17 00:00:00 2001
From: Donald Buczek <buczek@molgen.mpg.de>
Date: Wed, 14 Oct 2015 14:09:03 +0200
Subject: [PATCH] mxqd: don't attempt privileged operations when running as
 non-root

---
 mxqd.c | 41 ++++++++++++++++++++++-------------------
 1 file changed, 22 insertions(+), 19 deletions(-)

diff --git a/mxqd.c b/mxqd.c
index 0a00e0f..32fbf29 100644
--- a/mxqd.c
+++ b/mxqd.c
@@ -875,27 +875,30 @@ static int init_child_process(struct mxq_group_list *group, struct mxq_job *j)
                             g->user_name, g->user_uid, g->group_id, j->job_id);
     }
 
-    res = initgroups(passwd->pw_name, g->user_gid);
-    if (res == -1) {
-        mx_log_err("job=%s(%d):%lu:%lu initgroups() failed: %m",
-            g->user_name, g->user_uid, g->group_id, j->job_id);
-        return 0;
-    }
+    if(getuid()==0) {
 
-    res = setregid(g->user_gid, g->user_gid);
-    if (res == -1) {
-        mx_log_err("job=%s(%d):%lu:%lu setregid(%d, %d) failed: %m",
-            g->user_name, g->user_uid, g->group_id, j->job_id,
-            g->user_gid, g->user_gid);
-        return 0;
-    }
+        res = initgroups(passwd->pw_name, g->user_gid);
+        if (res == -1) {
+            mx_log_err("job=%s(%d):%lu:%lu initgroups() failed: %m",
+                g->user_name, g->user_uid, g->group_id, j->job_id);
+            return 0;
+        }
 
-    res = setreuid(g->user_uid, g->user_uid);
-    if (res == -1) {
-        mx_log_err("job=%s(%d):%lu:%lu setreuid(%d, %d) failed: %m",
-            g->user_name, g->user_uid, g->group_id, j->job_id,
-            g->user_uid, g->user_uid);
-        return 0;
+        res = setregid(g->user_gid, g->user_gid);
+        if (res == -1) {
+            mx_log_err("job=%s(%d):%lu:%lu setregid(%d, %d) failed: %m",
+                g->user_name, g->user_uid, g->group_id, j->job_id,
+                g->user_gid, g->user_gid);
+            return 0;
+        }
+
+        res = setreuid(g->user_uid, g->user_uid);
+        if (res == -1) {
+            mx_log_err("job=%s(%d):%lu:%lu setreuid(%d, %d) failed: %m",
+                g->user_name, g->user_uid, g->group_id, j->job_id,
+                g->user_uid, g->user_uid);
+            return 0;
+        }
     }
 
     res = chdir(j->job_workdir);