From a2faaa131711e5028ded2487a6d63c23bb54dfe6 Mon Sep 17 00:00:00 2001
From: Jay Kamat <jaygkamat@gmail.com>
Date: Tue, 31 Jul 2018 19:42:49 -0700
Subject: [PATCH] Fix duplicate entries and missing entries in
 getCgroupMountsHelper

Signed-off-by: Jay Kamat <jaygkamat@gmail.com>
---
 libcontainer/cgroups/utils.go | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/libcontainer/cgroups/utils.go b/libcontainer/cgroups/utils.go
index b7ff73f3..1a4c3e67 100644
--- a/libcontainer/cgroups/utils.go
+++ b/libcontainer/cgroups/utils.go
@@ -155,14 +155,16 @@ func getCgroupMountsHelper(ss map[string]bool, mi io.Reader, all bool) ([]Mount,
 			if !known || (!all && seen) {
 				continue
 			}
+			ss[opt] = true
 			if strings.HasPrefix(opt, cgroupNamePrefix) {
 				opt = opt[len(cgroupNamePrefix):]
 			}
 			m.Subsystems = append(m.Subsystems, opt)
-			ss[opt] = true
 			numFound++
 		}
-		res = append(res, m)
+		if len(m.Subsystems) > 0 || all {
+			res = append(res, m)
+		}
 	}
 	if err := scanner.Err(); err != nil {
 		return nil, err