Validate VolumePath against DB configuration

If this doesn't match, we end up not being able to access named
volumes mounted into containers, which is bad. Use the same
validation that we use for other critical paths to ensure this
one also matches.

Signed-off-by: Matthew Heon <matthew.heon@pm.me>

libpod/boltdb_state.go

@@ -261,12 +261,14 @@ func (s *BoltState) GetDBConfig() (*DBConfig, error) {
 		storageRoot := configBucket.Get(graphRootKey)
 		storageTmp := configBucket.Get(runRootKey)
 		graphDriver := configBucket.Get(graphDriverKey)
+		volumePath := configBucket.Get(volPathKey)
 
 		cfg.LibpodRoot = string(libpodRoot)
 		cfg.LibpodTmp = string(libpodTmp)
 		cfg.StorageRoot = string(storageRoot)
 		cfg.StorageTmp = string(storageTmp)
 		cfg.GraphDriver = string(graphDriver)
+		cfg.VolumePath = string(volumePath)
 
 		return nil
 	})

libpod/boltdb_state_internal.go

@@ -38,6 +38,7 @@ const (
 	graphRootName   = "graph-root"
 	graphDriverName = "graph-driver-name"
 	osName          = "os"
+	volPathName     = "volume-path"
 )
 
 var (
@@ -67,6 +68,7 @@ var (
 	graphRootKey   = []byte(graphRootName)
 	graphDriverKey = []byte(graphDriverName)
 	osKey          = []byte(osName)
+	volPathKey     = []byte(volPathName)
 )
 
 // Check if the configuration of the database is compatible with the
@@ -105,10 +107,15 @@ func checkRuntimeConfig(db *bolt.DB, rt *Runtime) error {
 			return err
 		}
 
-		return validateDBAgainstConfig(configBkt, "storage graph driver",
+		if err := validateDBAgainstConfig(configBkt, "storage graph driver",
 			rt.config.StorageConfig.GraphDriverName,
 			graphDriverKey,
-			storage.DefaultStoreOptions.GraphDriverName)
+			storage.DefaultStoreOptions.GraphDriverName); err != nil {
+			return err
+		}
+
+		return validateDBAgainstConfig(configBkt, "volume path",
+			rt.config.VolumePath, volPathKey, "")
 	})
 
 	return err

libpod/options.go

@@ -50,6 +50,7 @@ func WithStorageConfig(config storage.StoreOptions) RuntimeOption {
 			// Also set libpod volume path, so we are a subdirectory
 			// of the c/storage store by default
 			rt.config.VolumePath = filepath.Join(config.GraphRoot, "volumes")
+			rt.configuredFrom.volPathSet = true
 
 			setField = true
 		}
@@ -363,6 +364,7 @@ func WithVolumePath(volPath string) RuntimeOption {
 		}
 
 		rt.config.VolumePath = volPath
+		rt.configuredFrom.volPathSet = true
 
 		return nil
 	}

libpod/runtime.go

@@ -235,6 +235,7 @@ type runtimeConfiguredFrom struct {
 	storageRunRootSet     bool
 	libpodStaticDirSet    bool
 	libpodTmpDirSet       bool
+	volPathSet            bool
 }
 
 var (
@@ -645,12 +646,16 @@ func makeRuntime(runtime *Runtime) (err error) {
 	if !runtime.configuredFrom.libpodTmpDirSet && dbConfig.LibpodTmp != "" {
 		runtime.config.TmpDir = dbConfig.LibpodTmp
 	}
+	if !runtime.configuredFrom.volPathSet && dbConfig.VolumePath != "" {
+		runtime.config.VolumePath = dbConfig.VolumePath
+	}
 
 	logrus.Debugf("Using graph driver %s", runtime.config.StorageConfig.GraphDriverName)
 	logrus.Debugf("Using graph root %s", runtime.config.StorageConfig.GraphRoot)
 	logrus.Debugf("Using run root %s", runtime.config.StorageConfig.RunRoot)
 	logrus.Debugf("Using static dir %s", runtime.config.StaticDir)
 	logrus.Debugf("Using tmp dir %s", runtime.config.TmpDir)
+	logrus.Debugf("Using volume path %s", runtime.config.VolumePath)
 
 	// Validate our config against the database, now that we've set our
 	// final storage configuration

libpod/state.go

@@ -8,6 +8,7 @@ type DBConfig struct {
 	StorageRoot string
 	StorageTmp  string
 	GraphDriver string
+	VolumePath  string
 }
 
 // State is a storage backend for libpod's current state.