fix(api): return 404 for unknown weight-file model names instead of gallery fallthrough

The model-existence guard in SetModelAndConfig skipped the check for any
model name containing "/", to let diffusers-style HuggingFace "org/repo"
IDs download on the fly. But a name like "local/model.gguf" (the
parameters.model weight path, mistakenly passed as the request model)
also contains "/", so it bypassed the guard and silently fell through to
the gallery autoloader, which then attempted a surprising HuggingFace
download (issue #10162).

Tighten the guard so it only treats a "/"-containing name as a remote ID
when it does NOT end in a recognized model-file extension. Names that
point at a concrete weight file are now verified like any other, so a
wrong name returns a clear 404 while a loose weight file addressed by its
relative path (resolved by CheckIfModelExists against the models dir)
still passes.

The extension check reuses pkg/model's known-suffix list via the new
HasKnownModelFileExtension helper, so version-style suffixes like the
".0" in "stabilityai/stable-diffusion-xl-base-1.0" are correctly treated
as remote IDs.

Signed-off-by: Ettore Di Giacinto <mudler@localai.io>
Assisted-by: Claude:claude-opus-4-8 [Claude Code]

Author: mudler

core/http/middleware/request.go

@@ -152,9 +152,15 @@ func (re *RequestExtractor) SetModelAndConfig(initializer func() schema.LocalAIR
 
 			// If a model name was specified, verify it actually exists before proceeding.
 			// Check both configured models and loose model files in the model path.
-			// Skip the check for HuggingFace model IDs (contain "/") since backends
-			// like diffusers may download these on the fly.
-			if modelName != "" && !strings.Contains(modelName, "/") {
+			// Skip the check only for HuggingFace-style model IDs ("org/repo") that
+			// backends like diffusers may download on the fly. A name that points at a
+			// concrete weight file (e.g. "local/model.gguf") is NOT such an ID: it must
+			// still be verified, otherwise a wrong name silently falls through to the
+			// gallery autoloader and triggers a surprising download (issue #10162).
+			// CheckIfModelExists resolves relative paths against the models dir, so a
+			// loose weight file addressed by path still passes.
+			isRemoteModelID := strings.Contains(modelName, "/") && !model.HasKnownModelFileExtension(modelName)
+			if modelName != "" && !isRemoteModelID {
 				exists, existsErr := galleryop.CheckIfModelExists(re.modelConfigLoader, re.modelLoader, modelName, galleryop.ALWAYS_INCLUDE)
 				if existsErr == nil && !exists {
 					return c.JSON(http.StatusNotFound, schema.ErrorResponse{

core/http/middleware/request_test.go

@@ -140,6 +140,40 @@ var _ = Describe("SetModelAndConfig middleware", func() {
 		})
 	})
 
+	Context("when the model name is a file path to a weight that does not exist", func() {
+		// A name like "local/model.gguf" is the parameters.model weight path, not a
+		// HuggingFace org/repo ID. The slash must not exempt it from the existence
+		// check, otherwise a wrong name silently falls through to the gallery
+		// autoloader and triggers a surprising download (issue #10162).
+		It("returns 404 instead of passing through", func() {
+			rec := postJSON(app, "/v1/chat/completions",
+				`{"model":"local/missing-model.gguf","messages":[{"role":"user","content":"hi"}]}`)
+
+			Expect(rec.Code).To(Equal(http.StatusNotFound))
+
+			var resp schema.ErrorResponse
+			Expect(json.Unmarshal(rec.Body.Bytes(), &resp)).To(Succeed())
+			Expect(resp.Error).ToNot(BeNil())
+			Expect(resp.Error.Message).To(ContainSubstring("local/missing-model.gguf"))
+			Expect(resp.Error.Message).To(ContainSubstring("not found"))
+		})
+	})
+
+	Context("when the model name is a file path to a weight that exists on disk", func() {
+		// The same path, but the loose weight file is actually present in a
+		// subdirectory of the models path: the request must pass through so users
+		// can address a raw weight file by its relative path.
+		It("passes through to the handler", func() {
+			Expect(os.MkdirAll(filepath.Join(modelDir, "local"), 0755)).To(Succeed())
+			Expect(os.WriteFile(filepath.Join(modelDir, "local", "present-model.gguf"), []byte("weights"), 0644)).To(Succeed())
+
+			rec := postJSON(app, "/v1/chat/completions",
+				`{"model":"local/present-model.gguf","messages":[{"role":"user","content":"hi"}]}`)
+
+			Expect(rec.Code).To(Equal(http.StatusOK))
+		})
+	})
+
 	Context("when no model is specified", func() {
 		It("passes through without checking", func() {
 			rec := postJSON(app, "/v1/chat/completions",

pkg/model/loader.go

@@ -369,6 +369,28 @@ var knownModelsNameSuffixToSkip []string = []string{
 	".tar.gz",
 }
 
+// HasKnownModelFileExtension reports whether name ends in a file extension that
+// LocalAI recognizes as a model weight or asset file (e.g. ".gguf",
+// ".safetensors", ".json"). It is used to tell a concrete file path such as
+// "local/model.gguf" apart from a HuggingFace-style repository ID like
+// "org/repo": only the former carries a recognized suffix. A version-style
+// suffix such as the ".0" in "stabilityai/stable-diffusion-xl-base-1.0" is not
+// in the list, so such repo IDs are correctly treated as non-files.
+func HasKnownModelFileExtension(name string) bool {
+	lower := strings.ToLower(name)
+	for _, suffix := range knownModelsNameSuffixToSkip {
+		// "." is a guard entry consumed by ListFilesInModelPath, not a real
+		// extension; skip it so it doesn't match every dotted name.
+		if suffix == "." {
+			continue
+		}
+		if strings.HasSuffix(lower, strings.ToLower(suffix)) {
+			return true
+		}
+	}
+	return false
+}
+
 func (ml *ModelLoader) ListFilesInModelPath() ([]string, error) {
 	files, err := os.ReadDir(ml.ModelPath)
 	if err != nil {

pkg/model/loader_test.go

@@ -100,6 +100,23 @@ var _ = Describe("ModelLoader", func() {
 		})
 	})
 
+	Context("HasKnownModelFileExtension", func() {
+		It("returns true for concrete weight/asset file paths", func() {
+			Expect(model.HasKnownModelFileExtension("local/model.gguf")).To(BeTrue())
+			Expect(model.HasKnownModelFileExtension("model.safetensors")).To(BeTrue())
+			Expect(model.HasKnownModelFileExtension("foo/bar.GGUF")).To(BeTrue())
+			Expect(model.HasKnownModelFileExtension("config.json")).To(BeTrue())
+		})
+
+		It("returns false for HuggingFace-style repository IDs", func() {
+			// org/repo carries no recognized file extension...
+			Expect(model.HasKnownModelFileExtension("bartowski/DeepSeek-R1-Distill-Qwen-1.5B-GGUF")).To(BeFalse())
+			// ...and a version suffix like ".0" is not a known model extension.
+			Expect(model.HasKnownModelFileExtension("stabilityai/stable-diffusion-xl-base-1.0")).To(BeFalse())
+			Expect(model.HasKnownModelFileExtension("plain-model-name")).To(BeFalse())
+		})
+	})
+
 	Context("ListFilesInModelPath", func() {
 		It("should list all valid model files in the model path", func() {
 			os.Create(filepath.Join(modelPath, "test.model"))