Respect user-added mounts over default spec mounts

When there was a conflict between a user-added volume and a mount
already in the spec, we previously respected the mount already in
the spec and discarded the user-added mount. This is counter to
expected behavior - if I volume-mount /dev into the container, I
epxect it will override the default /dev in the container, and
not be ignored.

Signed-off-by: Matthew Heon <matthew.heon@gmail.com>

Closes: #1419
Approved by: TomSweeneyRedHat

1 files changed, 14 insertions, 10 deletions

diff --git a/pkg/spec/spec.go b/pkg/spec/spec.go
index 12b3b42b5..77dbf8b42 100644
--- a/pkg/spec/spec.go
+++ b/pkg/spec/spec.go
@@ -2,6 +2,7 @@ package createconfig
 
 import (
 	"os"
+	"path"
 	"strings"
 
 	"github.com/containers/libpod/libpod"
@@ -310,18 +311,21 @@ func CreateConfigToOCISpec(config *CreateConfig) (*spec.Spec, error) { //nolint
 	if err != nil {
 		return nil, errors.Wrapf(err, "error getting volume mounts")
 	}
-	// If we have overlappings mounts, remove them from the spec in favor of
-	// the user-added volume mounts
-	destinations := make(map[string]bool)
-	for _, mount := range mounts {
-		destinations[mount.Destination] = true
-	}
-	for _, mount := range configSpec.Mounts {
-		if _, ok := destinations[mount.Destination]; !ok {
-			mounts = append(mounts, mount)
+	if len(mounts) > 0 {
+		// If we have overlappings mounts, remove them from the spec in favor of
+		// the user-added volume mounts
+		destinations := make(map[string]bool)
+		for _, mount := range mounts {
+			destinations[path.Clean(mount.Destination)] = true
+		}
+		for _, mount := range configSpec.Mounts {
+			if _, ok := destinations[path.Clean(mount.Destination)]; !ok {
+				logrus.Debugf("Adding mount %s", mount.Destination)
+				mounts = append(mounts, mount)
+			}
 		}
+		configSpec.Mounts = mounts
 	}
-	configSpec.Mounts = mounts
 
 	if err := g.SetLinuxRootPropagation("shared"); err != nil {
 		return nil, errors.Wrapf(err, "failed to set propagation to rslave")