fix panic when scale values are negative

Signed-off-by: Guillaume Lours <[email protected]>

Author: glours

loader/validate.go

@@ -131,6 +131,13 @@ func checkConsistency(project *types.Project) error { //nolint:gocyclo
 			s.Deploy.Replicas = s.Scale
 		}
 
+		if s.Scale != nil && *s.Scale < 0 {
+			return fmt.Errorf("services.%s.scale: must be greater than or equal to 0", s.Name)
+		}
+		if s.Deploy != nil && s.Deploy.Replicas != nil && *s.Deploy.Replicas < 0 {
+			return fmt.Errorf("services.%s.deploy.replicas: must be greater than or equal to 0", s.Name)
+		}
+
 		if s.CPUS != 0 && s.Deploy != nil {
 			if s.Deploy.Resources.Limits != nil && s.Deploy.Resources.Limits.NanoCPUs.Value() != s.CPUS {
 				return fmt.Errorf("services.%s: can't set distinct values on 'cpus' and 'deploy.resources.limits.cpus': %w",

loader/validate_test.go

@@ -436,3 +436,31 @@ func TestValidateMountConflict(t *testing.T) {
 	err := checkConsistency(project)
 	assert.Error(t, err, "services.myservice.volumes[1]: target /conflict already mounted as services.myservice.tmpfs[1]")
 }
+
+func TestValidateNegativeScale(t *testing.T) {
+	project := &types.Project{
+		Services: types.Services{
+			"myservice": {
+				Name:  "myservice",
+				Image: "scratch",
+				Scale: ptr(-1),
+			},
+		},
+	}
+	err := checkConsistency(project)
+	assert.Error(t, err, "services.myservice.scale: must be greater than or equal to 0")
+
+	project = &types.Project{
+		Services: types.Services{
+			"myservice": {
+				Name:  "myservice",
+				Image: "scratch",
+				Deploy: &types.DeployConfig{
+					Replicas: ptr(-1),
+				},
+			},
+		},
+	}
+	err = checkConsistency(project)
+	assert.Error(t, err, "services.myservice.deploy.replicas: must be greater than or equal to 0")
+}