manifest: Fix crash on startup when trying to clean up unused files (#5840)

Currently if the config field is missing in the manifest file (or
corrupted), Ollama will crash when it tries to read it. This can
happen at startup or when pulling new models.

This data is mostly just used for showing model information so we
can be tolerant of it not being present - it is not required to
run the models. Besides avoiding crashing, this also gives us the
ability to restructure the config in the future by pulling it
into the main manifest file.

server/images.go

@@ -250,19 +250,21 @@ func GetModel(name string) (*Model, error) {
 		Template:  template.DefaultTemplate,
 	}
 
-	filename, err := GetBlobsPath(manifest.Config.Digest)
-	if err != nil {
-		return nil, err
-	}
+	if manifest.Config.Digest != "" {
+		filename, err := GetBlobsPath(manifest.Config.Digest)
+		if err != nil {
+			return nil, err
+		}
 
-	configFile, err := os.Open(filename)
-	if err != nil {
-		return nil, err
-	}
-	defer configFile.Close()
+		configFile, err := os.Open(filename)
+		if err != nil {
+			return nil, err
+		}
+		defer configFile.Close()
 
-	if err := json.NewDecoder(configFile).Decode(&model.Config); err != nil {
-		return nil, err
+		if err := json.NewDecoder(configFile).Decode(&model.Config); err != nil {
+			return nil, err
+		}
 	}
 
 	for _, layer := range manifest.Layers {
@@ -781,7 +783,7 @@ func PruneLayers() error {
 
 	err = deleteUnusedLayers(nil, deleteMap)
 	if err != nil {
-		slog.Info(fmt.Sprintf("couldn't remove unused layers: %v", err))
+		slog.Error(fmt.Sprintf("couldn't remove unused layers: %v", err))
 		return nil
 	}
 
@@ -839,7 +841,9 @@ func PushModel(ctx context.Context, name string, regOpts *registryOptions, fn fu
 
 	var layers []*Layer
 	layers = append(layers, manifest.Layers...)
-	layers = append(layers, manifest.Config)
+	if manifest.Config.Digest != "" {
+		layers = append(layers, &manifest.Config)
+	}
 
 	for _, layer := range layers {
 		if err := uploadBlob(ctx, mp, layer, regOpts, fn); err != nil {
@@ -890,7 +894,9 @@ func PullModel(ctx context.Context, name string, regOpts *registryOptions, fn fu
 			for _, l := range manifest.Layers {
 				deleteMap[l.Digest] = struct{}{}
 			}
-			deleteMap[manifest.Config.Digest] = struct{}{}
+			if manifest.Config.Digest != "" {
+				deleteMap[manifest.Config.Digest] = struct{}{}
+			}
 		}
 	}
 
@@ -907,7 +913,9 @@ func PullModel(ctx context.Context, name string, regOpts *registryOptions, fn fu
 
 	var layers []*Layer
 	layers = append(layers, manifest.Layers...)
-	layers = append(layers, manifest.Config)
+	if manifest.Config.Digest != "" {
+		layers = append(layers, &manifest.Config)
+	}
 
 	skipVerify := make(map[string]bool)
 	for _, layer := range layers {
@@ -971,7 +979,7 @@ func PullModel(ctx context.Context, name string, regOpts *registryOptions, fn fu
 		fn(api.ProgressResponse{Status: "removing any unused layers"})
 		err = deleteUnusedLayers(nil, deleteMap)
 		if err != nil {
-			slog.Info(fmt.Sprintf("couldn't remove unused layers: %v", err))
+			slog.Error(fmt.Sprintf("couldn't remove unused layers: %v", err))
 			fn(api.ProgressResponse{Status: fmt.Sprintf("couldn't remove unused layers: %v", err)})
 		}
 	}

server/layer.go

@@ -2,6 +2,7 @@ package server
 
 import (
 	"crypto/sha256"
+	"errors"
 	"fmt"
 	"io"
 	"os"
@@ -61,6 +62,10 @@ func NewLayer(r io.Reader, mediatype string) (*Layer, error) {
 }
 
 func NewLayerFromLayer(digest, mediatype, from string) (*Layer, error) {
+	if digest == "" {
+		return nil, errors.New("creating new layer from layer with empty digest")
+	}
+
 	blob, err := GetBlobsPath(digest)
 	if err != nil {
 		return nil, err
@@ -81,6 +86,10 @@ func NewLayerFromLayer(digest, mediatype, from string) (*Layer, error) {
 }
 
 func (l *Layer) Open() (io.ReadSeekCloser, error) {
+	if l.Digest == "" {
+		return nil, errors.New("opening layer with empty digest")
+	}
+
 	blob, err := GetBlobsPath(l.Digest)
 	if err != nil {
 		return nil, err
@@ -90,13 +99,17 @@ func (l *Layer) Open() (io.ReadSeekCloser, error) {
 }
 
 func (l *Layer) Remove() error {
+	if l.Digest == "" {
+		return nil
+	}
+
 	ms, err := Manifests()
 	if err != nil {
 		return err
 	}
 
 	for _, m := range ms {
-		for _, layer := range append(m.Layers, m.Config) {
+		for _, layer := range append(m.Layers, &m.Config) {
 			if layer.Digest == l.Digest {
 				// something is using this layer
 				return nil

server/manifest.go

@@ -16,7 +16,7 @@ import (
 type Manifest struct {
 	SchemaVersion int      `json:"schemaVersion"`
 	MediaType     string   `json:"mediaType"`
-	Config        *Layer   `json:"config"`
+	Config        Layer    `json:"config"`
 	Layers        []*Layer `json:"layers"`
 
 	filepath string
@@ -25,7 +25,7 @@ type Manifest struct {
 }
 
 func (m *Manifest) Size() (size int64) {
-	for _, layer := range append(m.Layers, m.Config) {
+	for _, layer := range append(m.Layers, &m.Config) {
 		size += layer.Size
 	}
 
@@ -46,11 +46,13 @@ func (m *Manifest) Remove() error {
 }
 
 func (m *Manifest) RemoveLayers() error {
-	for _, layer := range append(m.Layers, m.Config) {
-		if err := layer.Remove(); errors.Is(err, os.ErrNotExist) {
-			slog.Debug("layer does not exist", "digest", layer.Digest)
-		} else if err != nil {
-			return err
+	for _, layer := range append(m.Layers, &m.Config) {
+		if layer.Digest != "" {
+			if err := layer.Remove(); errors.Is(err, os.ErrNotExist) {
+				slog.Debug("layer does not exist", "digest", layer.Digest)
+			} else if err != nil {
+				return err
+			}
 		}
 	}
 
@@ -113,7 +115,7 @@ func WriteManifest(name model.Name, config *Layer, layers []*Layer) error {
 	m := Manifest{
 		SchemaVersion: 2,
 		MediaType:     "application/vnd.docker.distribution.manifest.v2+json",
-		Config:        config,
+		Config:        *config,
 		Layers:        layers,
 	}
 

server/routes.go

@@ -824,17 +824,20 @@ func (s *Server) ListModelsHandler(c *gin.Context) {
 
 	models := []api.ListModelResponse{}
 	for n, m := range ms {
-		f, err := m.Config.Open()
-		if err != nil {
-			slog.Warn("bad manifest filepath", "name", n, "error", err)
-			continue
-		}
-		defer f.Close()
-
 		var cf ConfigV2
-		if err := json.NewDecoder(f).Decode(&cf); err != nil {
-			slog.Warn("bad manifest config", "name", n, "error", err)
-			continue
+
+		if m.Config.Digest != "" {
+			f, err := m.Config.Open()
+			if err != nil {
+				slog.Warn("bad manifest filepath", "name", n, "error", err)
+				continue
+			}
+			defer f.Close()
+
+			if err := json.NewDecoder(f).Decode(&cf); err != nil {
+				slog.Warn("bad manifest config", "name", n, "error", err)
+				continue
+			}
 		}
 
 		// tag should never be masked