Add DB schema migrations for Vulnerability

This is the DB layout for first-class
vulnerabilities backend MVC. Added
vulnerabilities table, FK to it from
vulnerability_occurrences table, add all
required foreign keys for associations
between Vulnerability and other models

app/models/concerns/issuable.rb

@@ -4,7 +4,7 @@
 #
 # Contains common functionality shared between Issues and MergeRequests
 #
-# Used by Issue, MergeRequest
+# Used by Issue, MergeRequest, Epic
 #
 module Issuable
   extend ActiveSupport::Concern
@@ -26,6 +26,11 @@ module Issuable
   include IssuableStates
   include ClosedAtFilterable
 
+  TITLE_LENGTH_MAX = 255
+  TITLE_HTML_LENGTH_MAX = 800
+  DESCRIPTION_LENGTH_MAX = 16000
+  DESCRIPTION_HTML_LENGTH_MAX = 48000
+
   # This object is used to gather issuable meta data for displaying
   # upvotes, downvotes, notes and closing merge requests count for issues and merge requests
   # lists avoiding n+1 queries and improving performance.
@@ -72,10 +77,15 @@ module Issuable
              prefix: true
 
     validates :author, presence: true
-    validates :title, presence: true, length: { maximum: 255 }
-    validates :description, length: { maximum: Gitlab::Database::MAX_TEXT_SIZE_LIMIT }, allow_blank: true
+    validates :title, presence: true, length: { maximum: TITLE_LENGTH_MAX }
+    # we validate the description against DESCRIPTION_LENGTH_MAX only for Issuables being created
+    # to avoid breaking the existing Issuables which may have their descriptions longer
+    validates :description, length: { maximum: DESCRIPTION_LENGTH_MAX }, allow_blank: true, on: :create
+    validate :description_max_length_for_new_records_is_valid, on: :update
     validate :milestone_is_valid
 
+    before_validation :truncate_description_on_import!
+
     scope :authored, ->(user) { where(author_id: user) }
     scope :recent, -> { reorder(id: :desc) }
     scope :of_projects, ->(ids) { where(project_id: ids) }
@@ -138,6 +148,16 @@ module Issuable
     def milestone_is_valid
       errors.add(:milestone_id, message: "is invalid") if milestone_id.present? && !milestone_available?
     end
+
+    def description_max_length_for_new_records_is_valid
+      if new_record? && description.length > Issuable::DESCRIPTION_LENGTH_MAX
+        errors.add(:description, :too_long, count: Issuable::DESCRIPTION_LENGTH_MAX)
+      end
+    end
+
+    def truncate_description_on_import!
+      self.description = description&.slice(0, Issuable::DESCRIPTION_LENGTH_MAX) if importing?
+    end
   end
 
   class_methods do

db/migrate/20190929180751_create_vulnerabilities.rb

+# frozen_string_literal: true
+
+# See http://doc.gitlab.com/ce/development/migration_style_guide.html
+# for more information on how to write migrations for GitLab.
+
+class CreateVulnerabilities < ActiveRecord::Migration[5.2]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  def change
+    create_table :vulnerabilities do |t|
+      t.bigint "milestone_id"
+      t.bigint "epic_id"
+      t.bigint "project_id", null: false
+      t.bigint "author_id", null: false
+      t.bigint "updated_by_id"
+      t.bigint "last_edited_by_id"
+      t.bigint "start_date_sourcing_milestone_id"
+      t.bigint "due_date_sourcing_milestone_id"
+      t.bigint "closed_by_id"
+      t.datetime_with_timezone "last_edited_at"
+      t.datetime_with_timezone "created_at", null: false
+      t.datetime_with_timezone "updated_at", null: false
+      t.datetime_with_timezone "closed_at"
+      t.date "start_date"
+      t.date "due_date"
+      t.integer "state", limit: 2, default: 1, null: false # initially: open, closed
+      t.integer "severity", limit: 2, null: false # auto-calculated as highest-severity finding, but overrideable
+      t.integer "confidence", limit: 2, null: false # auto-calculated as lowest-confidence finding, but overrideable
+      t.boolean "severity_overridden", default: false
+      t.boolean "confidence_overridden", default: false
+      t.string "title", limit: 255, null: false
+      t.text "title_html", null: false
+      t.text "description"
+      t.text "description_html"
+    end
+  end
+end

db/migrate/20190929180813_add_reference_from_vulnerability_occurrences_to_occurrences.rb

+# frozen_string_literal: true
+
+# See http://doc.gitlab.com/ce/development/migration_style_guide.html
+# for more information on how to write migrations for GitLab.
+
+class AddReferenceFromVulnerabilityOccurrencesToOccurrences < ActiveRecord::Migration[5.2]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  def change
+    add_column :vulnerability_occurrences, :vulnerability_id, :bigint
+  end
+end

db/migrate/20190929180827_add_foreign_keys_and_indexes_to_vulnerabilities.rb

+# frozen_string_literal: true
+
+# See http://doc.gitlab.com/ce/development/migration_style_guide.html
+# for more information on how to write migrations for GitLab.
+
+class AddForeignKeysAndIndexesToVulnerabilities < ActiveRecord::Migration[5.2]
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    add_concurrent_index :vulnerabilities, :milestone_id
+    add_concurrent_foreign_key :vulnerabilities, :milestones, column: :milestone_id, on_delete: :nullify
+
+    add_concurrent_index :vulnerabilities, :epic_id
+    add_concurrent_foreign_key :vulnerabilities, :epics, column: :epic_id, on_delete: :nullify
+
+    add_concurrent_index :vulnerabilities, :project_id
+    add_concurrent_foreign_key :vulnerabilities, :projects, column: :project_id
+
+    add_concurrent_index :vulnerabilities, :author_id
+    add_concurrent_foreign_key :vulnerabilities, :users, column: :author_id, on_delete: :nullify
+
+    add_concurrent_index :vulnerabilities, :updated_by_id
+    add_concurrent_foreign_key :vulnerabilities, :users, column: :updated_by_id, on_delete: :nullify
+
+    add_concurrent_index :vulnerabilities, :last_edited_by_id
+    add_concurrent_foreign_key :vulnerabilities, :users, column: :last_edited_by_id, on_delete: :nullify
+
+    add_concurrent_index :vulnerabilities, :closed_by_id
+    add_concurrent_foreign_key :vulnerabilities, :users, column: :closed_by_id, on_delete: :nullify
+
+    add_concurrent_index :vulnerabilities, :start_date_sourcing_milestone_id
+    add_concurrent_foreign_key :vulnerabilities, :milestones, column: :start_date_sourcing_milestone_id, on_delete: :nullify
+
+    add_concurrent_index :vulnerabilities, :due_date_sourcing_milestone_id
+    add_concurrent_foreign_key :vulnerabilities, :milestones, column: :due_date_sourcing_milestone_id, on_delete: :nullify
+
+    add_concurrent_index :vulnerability_occurrences, :vulnerability_id
+    add_concurrent_foreign_key :vulnerability_occurrences, :vulnerabilities, column: :vulnerability_id, on_delete: :nullify
+  end
+
+  def down
+    remove_foreign_key :vulnerability_occurrences, :vulnerabilities
+    remove_concurrent_index :vulnerability_occurrences, :vulnerability_id
+
+    remove_foreign_key :vulnerabilities, column: :due_date_sourcing_milestone_id
+    remove_concurrent_index :vulnerabilities, :due_date_sourcing_milestone_id
+
+    remove_foreign_key :vulnerabilities, column: :start_date_sourcing_milestone_id
+    remove_concurrent_index :vulnerabilities, :start_date_sourcing_milestone_id
+
+    remove_foreign_key :vulnerabilities, column: :closed_by_id
+    remove_concurrent_index :vulnerabilities, :closed_by_id
+
+    remove_foreign_key :vulnerabilities, column: :last_edited_by_id
+    remove_concurrent_index :vulnerabilities, :last_edited_by_id
+
+    remove_foreign_key :vulnerabilities, column: :updated_by_id
+    remove_concurrent_index :vulnerabilities, :updated_by_id
+
+    remove_foreign_key :vulnerabilities, column: :author_id
+    remove_concurrent_index :vulnerabilities, :author_id
+
+    remove_foreign_key :vulnerabilities, :projects
+    remove_concurrent_index :vulnerabilities, :project_id
+
+    remove_foreign_key :vulnerabilities, :epics
+    remove_concurrent_index :vulnerabilities, :epic_id
+
+    remove_foreign_key :vulnerabilities, :milestones
+    remove_concurrent_index :vulnerabilities, :milestone_id
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2019_09_27_074328) do
+ActiveRecord::Schema.define(version: 2019_09_29_180827) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "pg_trgm"
@@ -3705,6 +3705,42 @@ ActiveRecord::Schema.define(version: 2019_09_27_074328) do
     t.index ["user_id", "project_id"], name: "index_users_star_projects_on_user_id_and_project_id", unique: true
   end
 
+  create_table "vulnerabilities", force: :cascade do |t|
+    t.bigint "milestone_id"
+    t.bigint "epic_id"
+    t.bigint "project_id", null: false
+    t.bigint "author_id", null: false
+    t.bigint "updated_by_id"
+    t.bigint "last_edited_by_id"
+    t.date "start_date"
+    t.date "due_date"
+    t.datetime_with_timezone "last_edited_at"
+    t.datetime_with_timezone "created_at", null: false
+    t.datetime_with_timezone "updated_at", null: false
+    t.string "title", limit: 255, null: false
+    t.text "title_html", null: false
+    t.text "description"
+    t.text "description_html"
+    t.bigint "start_date_sourcing_milestone_id"
+    t.bigint "due_date_sourcing_milestone_id"
+    t.bigint "closed_by_id"
+    t.datetime_with_timezone "closed_at"
+    t.integer "state", limit: 2, default: 1, null: false
+    t.integer "severity", limit: 2, null: false
+    t.boolean "severity_overridden", default: false
+    t.integer "confidence", limit: 2, null: false
+    t.boolean "confidence_overridden", default: false
+    t.index ["author_id"], name: "index_vulnerabilities_on_author_id"
+    t.index ["closed_by_id"], name: "index_vulnerabilities_on_closed_by_id"
+    t.index ["due_date_sourcing_milestone_id"], name: "index_vulnerabilities_on_due_date_sourcing_milestone_id"
+    t.index ["epic_id"], name: "index_vulnerabilities_on_epic_id"
+    t.index ["last_edited_by_id"], name: "index_vulnerabilities_on_last_edited_by_id"
+    t.index ["milestone_id"], name: "index_vulnerabilities_on_milestone_id"
+    t.index ["project_id"], name: "index_vulnerabilities_on_project_id"
+    t.index ["start_date_sourcing_milestone_id"], name: "index_vulnerabilities_on_start_date_sourcing_milestone_id"
+    t.index ["updated_by_id"], name: "index_vulnerabilities_on_updated_by_id"
+  end
+
   create_table "vulnerability_feedback", id: :serial, force: :cascade do |t|
     t.datetime_with_timezone "created_at", null: false
     t.datetime_with_timezone "updated_at", null: false
@@ -3772,10 +3808,12 @@ ActiveRecord::Schema.define(version: 2019_09_27_074328) do
     t.string "name", null: false
     t.string "metadata_version", null: false
     t.text "raw_metadata", null: false
+    t.bigint "vulnerability_id"
     t.index ["primary_identifier_id"], name: "index_vulnerability_occurrences_on_primary_identifier_id"
     t.index ["project_id", "primary_identifier_id", "location_fingerprint", "scanner_id"], name: "index_vulnerability_occurrences_on_unique_keys", unique: true
     t.index ["scanner_id"], name: "index_vulnerability_occurrences_on_scanner_id"
     t.index ["uuid"], name: "index_vulnerability_occurrences_on_uuid", unique: true
+    t.index ["vulnerability_id"], name: "index_vulnerability_occurrences_on_vulnerability_id"
   end
 
   create_table "vulnerability_scanners", force: :cascade do |t|
@@ -4202,6 +4240,15 @@ ActiveRecord::Schema.define(version: 2019_09_27_074328) do
   add_foreign_key "users_ops_dashboard_projects", "projects", on_delete: :cascade
   add_foreign_key "users_ops_dashboard_projects", "users", on_delete: :cascade
   add_foreign_key "users_star_projects", "projects", name: "fk_22cd27ddfc", on_delete: :cascade
+  add_foreign_key "vulnerabilities", "epics", name: "fk_1d37cddf91", on_delete: :nullify
+  add_foreign_key "vulnerabilities", "milestones", column: "due_date_sourcing_milestone_id", name: "fk_7c5bb22a22", on_delete: :nullify
+  add_foreign_key "vulnerabilities", "milestones", column: "start_date_sourcing_milestone_id", name: "fk_88b4d546ef", on_delete: :nullify
+  add_foreign_key "vulnerabilities", "milestones", name: "fk_131d289c65", on_delete: :nullify
+  add_foreign_key "vulnerabilities", "projects", name: "fk_efb96ab1e2", on_delete: :cascade
+  add_foreign_key "vulnerabilities", "users", column: "author_id", name: "fk_b1de915a15", on_delete: :nullify
+  add_foreign_key "vulnerabilities", "users", column: "closed_by_id", name: "fk_cf5c60acbf", on_delete: :nullify
+  add_foreign_key "vulnerabilities", "users", column: "last_edited_by_id", name: "fk_1302949740", on_delete: :nullify
+  add_foreign_key "vulnerabilities", "users", column: "updated_by_id", name: "fk_7ac31eacb9", on_delete: :nullify
   add_foreign_key "vulnerability_feedback", "ci_pipelines", column: "pipeline_id", on_delete: :nullify
   add_foreign_key "vulnerability_feedback", "issues", on_delete: :nullify
   add_foreign_key "vulnerability_feedback", "merge_requests", name: "fk_563ff1912e", on_delete: :nullify
@@ -4214,6 +4261,7 @@ ActiveRecord::Schema.define(version: 2019_09_27_074328) do
   add_foreign_key "vulnerability_occurrence_pipelines", "ci_pipelines", column: "pipeline_id", on_delete: :cascade
   add_foreign_key "vulnerability_occurrence_pipelines", "vulnerability_occurrences", column: "occurrence_id", on_delete: :cascade
   add_foreign_key "vulnerability_occurrences", "projects", on_delete: :cascade
+  add_foreign_key "vulnerability_occurrences", "vulnerabilities", name: "fk_97ffe77653", on_delete: :nullify
   add_foreign_key "vulnerability_occurrences", "vulnerability_identifiers", column: "primary_identifier_id", on_delete: :cascade
   add_foreign_key "vulnerability_occurrences", "vulnerability_scanners", column: "scanner_id", on_delete: :cascade
   add_foreign_key "vulnerability_scanners", "projects", on_delete: :cascade

doc/development/README.md

@@ -34,6 +34,7 @@ description: 'Learn how to contribute to GitLab.'
 ## Backend guides
 
 - [GitLab utilities](utilities.md)
+- [Issuable-like Rails models](issuable-like-models.md)
 - [Logging](logging.md)
 - [API styleguide](api_styleguide.md) Use this styleguide if you are
   contributing to the API

doc/development/issuable-like-models.md

+# Issuable-like Rails models utilities
+
+GitLab Rails codebase contains several models that hold common functionality and behave similarly to an [Issue]. Other
+examples of `Issuable`s are [Merge Requests] and [Epics].
+
+This guide accumulates guidelines on working with such Rails models.
+
+## Important text fields
+
+There are max length constraints for the most important text fields for `Issuable`s:
+
+- `title`: 255 chars
+- `title_html`: 800 chars
+- `description`: 16000 chars
+- `description_html`: 48000 chars
+
+[Issue]: https://docs.gitlab.com/ee/user/project/issues
+[Merge Requests]: https://docs.gitlab.com/ee/user/project/merge_requests
+[Epics]: https://docs.gitlab.com/ee/user/group/epics

ee/app/models/ee/ci/pipeline.rb

@@ -17,7 +17,7 @@ module EE
 
         has_many :job_artifacts, through: :builds
         has_many :vulnerabilities_occurrence_pipelines, class_name: 'Vulnerabilities::OccurrencePipeline'
-        has_many :vulnerabilities, source: :occurrence, through: :vulnerabilities_occurrence_pipelines, class_name: 'Vulnerabilities::Occurrence'
+        has_many :vulnerability_findings, source: :occurrence, through: :vulnerabilities_occurrence_pipelines, class_name: 'Vulnerabilities::Occurrence'
 
         has_one :source_pipeline, class_name: "::Ci::Sources::Pipeline", inverse_of: :pipeline
         has_many :sourced_pipelines, class_name: "::Ci::Sources::Pipeline", foreign_key: :source_pipeline_id

ee/app/models/ee/project.rb

@@ -61,10 +61,15 @@ module EE
       has_many :audit_events, as: :entity
       has_many :designs, inverse_of: :project, class_name: 'DesignManagement::Design'
       has_many :path_locks
+
+      # the rationale behind vulnerabilities and vulnerability_findings can be found here:
+      # https://gitlab.com/gitlab-org/gitlab/issues/10252#terminology
+      has_many :vulnerabilities
       has_many :vulnerability_feedback, class_name: 'Vulnerabilities::Feedback'
-      has_many :vulnerabilities, class_name: 'Vulnerabilities::Occurrence'
+      has_many :vulnerability_findings, class_name: 'Vulnerabilities::Occurrence'
       has_many :vulnerability_identifiers, class_name: 'Vulnerabilities::Identifier'
       has_many :vulnerability_scanners, class_name: 'Vulnerabilities::Scanner'
+
       has_many :protected_environments
       has_many :software_license_policies, inverse_of: :project, class_name: 'SoftwareLicensePolicy'
       accepts_nested_attributes_for :software_license_policies, allow_destroy: true

ee/app/models/vulnerability.rb

+# frozen_string_literal: true
+
+class Vulnerability < ApplicationRecord
+  belongs_to :project
+  belongs_to :milestone
+  belongs_to :epic
+
+  belongs_to :author, class_name: 'User'
+  belongs_to :updated_by, class_name: 'User'
+  belongs_to :last_edited_by, class_name: 'User'
+  belongs_to :closed_by, class_name: 'User'
+
+  enum state: { opened: 1, closed: 2 }
+  enum severity: Vulnerabilities::Occurrence::SEVERITY_LEVELS, _prefix: :severity
+  enum confidence: Vulnerabilities::Occurrence::CONFIDENCE_LEVELS, _prefix: :confidence
+
+  validates :project, :author, :title, :title_html, :severity, :confidence, presence: true
+
+  # at this stage Vulnerability is not an Issuable, has some important attributes (and their constraints) in common
+  validates :title, length: { maximum: Issuable::TITLE_LENGTH_MAX }
+  validates :title_html, length: { maximum: Issuable::TITLE_HTML_LENGTH_MAX }, allow_blank: true
+  validates :description, length: { maximum: Issuable::DESCRIPTION_LENGTH_MAX }, allow_blank: true
+  validates :description_html, length: { maximum: Issuable::DESCRIPTION_HTML_LENGTH_MAX }, allow_blank: true
+end

ee/app/services/security/store_report_service.rb

@@ -26,17 +26,17 @@ module Security
     private
 
     def executed?
-      pipeline.vulnerabilities.report_type(@report.type).any?
+      pipeline.vulnerability_findings.report_type(@report.type).any?
     end
 
     def create_all_vulnerabilities!
       @report.occurrences.each do |occurrence|
-        create_vulnerability(occurrence)
+        create_vulnerability_finding(occurrence)
       end
     end
 
-    def create_vulnerability(occurrence)
-      vulnerability = create_or_find_vulnerability_object(occurrence)
+    def create_vulnerability_finding(occurrence)
+      vulnerability = create_or_find_vulnerability_finding(occurrence)
 
       occurrence.identifiers.map do |identifier|
         create_vulnerability_identifier_object(vulnerability, identifier)
@@ -46,7 +46,7 @@ module Security
     end
 
     # rubocop: disable CodeReuse/ActiveRecord
-    def create_or_find_vulnerability_object(occurrence)
+    def create_or_find_vulnerability_finding(occurrence)
       find_params = {
         scanner: scanners_objects[occurrence.scanner.key],
         primary_identifier: identifiers_objects[occurrence.primary_identifier.key],
@@ -57,11 +57,12 @@ module Security
         .except(:compare_key, :identifiers, :location, :scanner)
 
       begin
-        project.vulnerabilities
+        project
+          .vulnerability_findings
           .create_with(create_params)
           .find_or_create_by!(find_params)
       rescue ActiveRecord::RecordNotUnique
-        project.vulnerabilities.find_by!(find_params)
+        project.vulnerability_findings.find_by!(find_params)
       end
     end
     # rubocop: enable CodeReuse/ActiveRecord

ee/db/fixtures/development/20_vulnerabilities.rb

@@ -35,7 +35,7 @@ class Gitlab::Seeder::Vulnerabilities
   private
 
   def create_occurrence(rank, primary_identifier)
-    project.vulnerabilities.create!(
+    project.vulnerability_findings.create!(
       uuid: random_uuid,
       name: 'Cipher with no integrity',
       report_type: :sast,

ee/spec/factories/vulnerabilities.rb

+# frozen_string_literal: true
+
+FactoryBot.define do
+  factory :vulnerability do
+    project
+    author
+    title { generate(:title) }
+    title_html { "<h2>#{title}</h2>" }
+    severity { :high }
+    confidence { :medium }
+
+    trait :opened do
+      state { :opened }
+    end
+
+    trait :closed do
+      state { :closed }
+      closed_at { Time.now }
+    end
+  end
+end

ee/spec/models/ci/pipeline_spec.rb

@@ -16,7 +16,7 @@ describe Ci::Pipeline do
   it { is_expected.to have_many(:triggered_pipelines) }
   it { is_expected.to have_many(:downstream_bridges) }
   it { is_expected.to have_many(:job_artifacts).through(:builds) }
-  it { is_expected.to have_many(:vulnerabilities).through(:vulnerabilities_occurrence_pipelines).class_name('Vulnerabilities::Occurrence') }
+  it { is_expected.to have_many(:vulnerability_findings).through(:vulnerabilities_occurrence_pipelines).class_name('Vulnerabilities::Occurrence') }
   it { is_expected.to have_many(:vulnerabilities_occurrence_pipelines).class_name('Vulnerabilities::OccurrencePipeline') }
 
   describe '.failure_reasons' do

ee/spec/models/concerns/ee/issuable_spec.rb

@@ -15,7 +15,10 @@ describe EE::Issuable do
       it { is_expected.to validate_presence_of(:author) }
       it { is_expected.to validate_presence_of(:title) }
       it { is_expected.to validate_length_of(:title).is_at_most(255) }
-      it { is_expected.to validate_length_of(:description).is_at_most(1_000_000) }
+      it { is_expected.to validate_length_of(:description).is_at_most(16_000).on(:create) }
+
+      it_behaves_like 'validates description length with custom validation'
+      it_behaves_like 'truncates the description to its allowed maximum length on import'
     end
   end
 

ee/spec/models/vulnerability_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Vulnerability do
+  let(:severity_values) do
+    { undefined: 0,
+      info: 1,
+      unknown: 2,
+      low: 4,
+      medium: 5,
+      high: 6,
+      critical: 7 }
+  end
+  let(:confidence_values) do
+    { undefined: 0,
+      ignore: 1,
+      unknown: 2,
+      experimental: 3,
+      low: 4,
+      medium: 5,
+      high: 6,
+      confirmed: 7 }
+  end
+
+  it { is_expected.to define_enum_for(:state) }
+  it { is_expected.to define_enum_for(:severity).with_values(severity_values).with_prefix(:severity) }
+  it { is_expected.to define_enum_for(:confidence).with_values(confidence_values).with_prefix(:confidence) }
+
+  describe 'associations' do
+    subject { build(:vulnerability) }
+
+    it { is_expected.to belong_to(:project) }
+    it { is_expected.to belong_to(:milestone) }
+    it { is_expected.to belong_to(:epic) }
+
+    it { is_expected.to belong_to(:author).class_name('User') }
+    it { is_expected.to belong_to(:updated_by).class_name('User') }
+    it { is_expected.to belong_to(:last_edited_by).class_name('User') }
+    it { is_expected.to belong_to(:closed_by).class_name('User') }
+  end
+
+  describe 'validations' do
+    subject { build(:vulnerability) }
+
+    it { is_expected.to validate_presence_of(:project) }
+    it { is_expected.to validate_presence_of(:author) }
+    it { is_expected.to validate_presence_of(:title) }
+    it { is_expected.to validate_presence_of(:title_html) }
+    it { is_expected.to validate_presence_of(:severity) }
+    it { is_expected.to validate_presence_of(:confidence) }
+
+    it { is_expected.to validate_length_of(:title).is_at_most(255) }
+    it { is_expected.to validate_length_of(:title_html).is_at_most(800) }
+    it { is_expected.to validate_length_of(:description).is_at_most(16_000).allow_nil }
+    it { is_expected.to validate_length_of(:description_html).is_at_most(48_000).allow_nil }
+  end
+end

spec/lib/gitlab/import_export/all_models.yml

@@ -172,7 +172,7 @@ ci_pipelines:
 - downstream_bridges
 - job_artifacts
 - vulnerabilities_occurrence_pipelines
-- vulnerabilities
+- vulnerability_findings
 pipeline_variables:
 - pipeline
 stages:
@@ -389,6 +389,7 @@ project:
 - sourced_pipelines
 - prometheus_metrics
 - vulnerabilities
+- vulnerability_findings
 - vulnerability_feedback
 - vulnerability_identifiers
 - vulnerability_scanners

spec/models/concerns/issuable_spec.rb

@@ -46,7 +46,10 @@ describe Issuable do
       it { is_expected.to validate_presence_of(:author) }
       it { is_expected.to validate_presence_of(:title) }
       it { is_expected.to validate_length_of(:title).is_at_most(255) }
-      it { is_expected.to validate_length_of(:description).is_at_most(1_000_000) }
+      it { is_expected.to validate_length_of(:description).is_at_most(16_000).on(:create) }
+
+      it_behaves_like 'validates description length with custom validation'
+      it_behaves_like 'truncates the description to its allowed maximum length on import'
     end
 
     describe 'milestone' do

spec/support/shared_examples/models/concern/issuable_shared_examples.rb

+# frozen_string_literal: true
+
 shared_examples_for 'matches_cross_reference_regex? fails fast' do
   it 'fails fast for long strings' do
     # took well under 1 second in CI https://dev.gitlab.org/gitlab/gitlabhq/merge_requests/3267#note_172823
@@ -6,3 +8,59 @@ shared_examples_for 'matches_cross_reference_regex? fails fast' do
     end.not_to raise_error
   end
 end
+
+shared_examples_for 'validates description length with custom validation' do
+  let(:issuable) { build(:issue, description: 'x' * 16_001) }
+  let(:context) { :update }
+
+  subject { issuable.validate(context) }
+
+  context 'when Issuable is a new record' do
+    it 'validates the maximum description length' do
+      subject
+      expect(issuable.errors[:description]).to eq(["is too long (maximum is 16000 characters)"])
+    end
+
+    context 'on create' do
+      let(:context) { :create }
+
+      it 'does not validate the maximum description length' do
+        allow(issuable).to receive(:description_max_length_for_new_records_is_valid).and_call_original
+
+        subject
+
+        expect(issuable).not_to have_received(:description_max_length_for_new_records_is_valid)
+      end
+    end
+  end
+
+  context 'when Issuable is an existing record' do
+    before do
+      allow(issuable).to receive(:expire_etag_cache) # to skip the expire_etag_cache callback
+
+      issuable.save!(validate: false)
+    end
+
+    it 'does not validate the maximum description length' do
+      subject
+      expect(issuable.errors).not_to have_key(:description)
+    end
+  end
+end
+
+shared_examples_for 'truncates the description to its allowed maximum length on import' do
+  before do
+    allow(issuable).to receive(:importing?).and_return(true)
+  end
+
+  let(:issuable) { build(:issue, description: 'x' * 16_001) }
+
+  subject { issuable.validate(:create) }
+
+  it 'truncates the description to its allowed maximum length' do
+    subject
+
+    expect(issuable.description).to eq('x' * 16_000)
+    expect(issuable.errors[:description]).to be_empty
+  end
+end