Add docs for confidential issues

[ci skip]

9 files changed, 86 insertions, 14 deletions

diff --git a/doc/user/permissions.md b/doc/user/permissions.md
index 5ada8748d85..678fc3ffd1f 100644
--- a/doc/user/permissions.md
+++ b/doc/user/permissions.md
@@ -19,10 +19,12 @@ The following table depicts the various user permission levels in a project.
 | Action                                | Guest   | Reporter   | Developer   | Master   | Owner  |
 |---------------------------------------|---------|------------|-------------|----------|--------|
 | Create new issue                      | ✓       | ✓          | ✓           | ✓        | ✓      |
+| Create confidential issue             | ✓       | ✓          | ✓           | ✓        | ✓      |
+| View confidential issues              | (✓) [^1] | ✓          | ✓           | ✓        | ✓      |
 | Leave comments                        | ✓       | ✓          | ✓           | ✓        | ✓      |
-| See a list of builds                  | ✓ [^1]  | ✓          | ✓           | ✓        | ✓      |
-| See a build log                       | ✓ [^1]  | ✓          | ✓           | ✓        | ✓      |
-| Download and browse build artifacts   | ✓ [^1]  | ✓          | ✓           | ✓        | ✓      |
+| See a list of builds                  | ✓ [^2]  | ✓          | ✓           | ✓        | ✓      |
+| See a build log                       | ✓ [^2]  | ✓          | ✓           | ✓        | ✓      |
+| Download and browse build artifacts   | ✓ [^2]  | ✓          | ✓           | ✓        | ✓      |
 | View wiki pages                       | ✓       | ✓          | ✓           | ✓        | ✓      |
 | Pull project code                     |         | ✓          | ✓           | ✓        | ✓      |
 | Download project                      |         | ✓          | ✓           | ✓        | ✓      |
@@ -63,11 +65,8 @@ The following table depicts the various user permission levels in a project.
 | Switch visibility level               |         |            |             |          | ✓      |
 | Transfer project to another namespace |         |            |             |          | ✓      |
 | Remove project                        |         |            |             |          | ✓      |
-| Force push to protected branches [^2] |         |            |             |          |        |
-| Remove protected branches [^2]        |         |            |             |          |        |
-
-[^1]: If **Public pipelines** is enabled in **Project Settings > CI/CD Pipelines**
-[^2]: Not allowed for Guest, Reporter, Developer, Master, or Owner
+| Force push to protected branches [^3] |         |            |             |          |        |
+| Remove protected branches [^3]        |         |            |             |          |        |
 
 ## Group
 
@@ -156,17 +155,20 @@ users:
 | Run CI build                                |                 | ✓           | ✓        | ✓      |
 | Clone source and LFS from current project   |                 | ✓           | ✓        | ✓      |
 | Clone source and LFS from public projects   |                 | ✓           | ✓        | ✓      |
-| Clone source and LFS from internal projects |                 | ✓ [^3]      | ✓ [^3]   | ✓      |
-| Clone source and LFS from private projects  |                 | ✓ [^4]      | ✓ [^4]   | ✓ [^4] |
+| Clone source and LFS from internal projects |                 | ✓ [^4]      | ✓ [^4]   | ✓      |
+| Clone source and LFS from private projects  |                 | ✓ [^5]      | ✓ [^5]   | ✓ [^5] |
 | Push source and LFS                         |                 |             |          |        |
 | Pull container images from current project  |                 | ✓           | ✓        | ✓      |
 | Pull container images from public projects  |                 | ✓           | ✓        | ✓      |
-| Pull container images from internal projects|                 | ✓ [^3]      | ✓ [^3]   | ✓      |
-| Pull container images from private projects |                 | ✓ [^4]      | ✓ [^4]   | ✓ [^4] |
+| Pull container images from internal projects|                 | ✓ [^4]      | ✓ [^4]   | ✓      |
+| Pull container images from private projects |                 | ✓ [^5]      | ✓ [^5]   | ✓ [^5] |
 | Push container images to current project    |                 | ✓           | ✓        | ✓      |
 | Push container images to other projects     |                 |             |          |        |
 
-[^3]: Only if user is not external one.
-[^4]: Only if user is a member of the project.
+[^1]: Guest users can only view the confidential issues they created themselves
+[^2]: If **Public pipelines** is enabled in **Project Settings > CI/CD Pipelines**
+[^3]: Not allowed for Guest, Reporter, Developer, Master, or Owner
+[^4]: Only if user is not external one.
+[^5]: Only if user is a member of the project.
 [ce-18994]: https://gitlab.com/gitlab-org/gitlab-ce/issues/18994
 [new-mod]: project/new_ci_build_permissions_model.md
diff --git a/doc/user/project/issues/confidential_issues.md b/doc/user/project/issues/confidential_issues.md
new file mode 100644
index 00000000000..a1563a3e076
--- /dev/null
+++ b/doc/user/project/issues/confidential_issues.md
@@ -0,0 +1,67 @@
+# Confidential issues
+
+> Introduced in GitLab 8.6.
+
+Confidential issues are issues visible only to members of a project with
+[sufficient permissions](#permissions-and-access-to-confidential-issues).
+Confidential issues can be used by open source projects and companies alike to
+keep security vulnerabilities private or prevent surprises from leaking out.
+
+## Making an issue confidential
+
+You can make an issue confidential either by creating a new issue or editing
+an existing one.
+
+When you create a new issue, a checkbox right below the text area is available
+to mark the issue as confidential. Check that box and hit the **Submit issue**
+button to create the issue. For existing issues, edit them, check the
+confidential checkbox and hit **Save changes**.
+
+![Creating a new confidential issue](img/confidential_issues_create.png)
+
+## Making an issue non-confidential
+
+To make an issue non-confidential, all you have to do is edit it and unmark
+the confidential checkbox. Once you save the issue, it will gain the default
+visibility level you have chosen for your project.
+
+Every change from regular to confidential and vice versa, is indicated by a
+system note in the issue's comments.
+
+![Confidential issues system notes](img/confidential_issues_system_notes.png)
+
+## Indications of a confidential issue
+
+>**Note:** If you don't have [enough permissions](#permissions-and-access-to-confidential-issues),
+you won't be able to see the confidential issues at all.
+
+There are a few things that visually separate a confidential issue from a
+regular one. In the issues index page view, you can see the eye-slash icon
+next to the issues that are marked as confidential.
+
+![Confidential issues index page](img/confidential_issues_index_page.png)
+
+---
+
+Likewise, while inside the issue, you can see the eye-slash icon right next to
+the issue number, but there is also an indicator in the comment area that the
+issue you are commenting on is confidential.
+
+![Confidential issue page](img/confidential_issues_issue_page.png)
+
+## Permissions and access to confidential issues
+
+There are two kinds of level access for confidential issues. The general rule
+is that confidential issues are visible only to members of a project with at
+least [Reporter access][permissions]. However, a guest user can also create
+confidential issues, but can only view the ones that they created themselves.
+
+Confidential issues are also hidden in search results for unprivileged users.
+For example, here's what a user with Master and Guest access sees in the
+project's search results respectively.
+
+| Master access | Guest access |
+| :-----------: | :----------: |
+| ![Confidential issues search master](img/confidential_issues_search_master.png) | ![Confidential issues search guest](img/confidential_issues_search_guest.png) |
+
+[permissions]: ../../permissions.md#project
diff --git a/doc/user/project/issues/img/confidential_issues_create.png b/doc/user/project/issues/img/confidential_issues_create.png
new file mode 100644
index 00000000000..4e6be3cc431
--- /dev/null
+++ b/doc/user/project/issues/img/confidential_issues_create.png
diff --git a/doc/user/project/issues/img/confidential_issues_index_page.png b/doc/user/project/issues/img/confidential_issues_index_page.png
new file mode 100644
index 00000000000..042461e2451
--- /dev/null
+++ b/doc/user/project/issues/img/confidential_issues_index_page.png
diff --git a/doc/user/project/issues/img/confidential_issues_issue_page.png b/doc/user/project/issues/img/confidential_issues_issue_page.png
new file mode 100644
index 00000000000..b3568e9303a
--- /dev/null
+++ b/doc/user/project/issues/img/confidential_issues_issue_page.png
diff --git a/doc/user/project/issues/img/confidential_issues_search_guest.png b/doc/user/project/issues/img/confidential_issues_search_guest.png
new file mode 100644
index 00000000000..1af3d04d507
--- /dev/null
+++ b/doc/user/project/issues/img/confidential_issues_search_guest.png
diff --git a/doc/user/project/issues/img/confidential_issues_search_master.png b/doc/user/project/issues/img/confidential_issues_search_master.png
new file mode 100644
index 00000000000..b2edeb6094a
--- /dev/null
+++ b/doc/user/project/issues/img/confidential_issues_search_master.png
diff --git a/doc/user/project/issues/img/confidential_issues_system_notes.png b/doc/user/project/issues/img/confidential_issues_system_notes.png
new file mode 100644
index 00000000000..4005f9350f7
--- /dev/null
+++ b/doc/user/project/issues/img/confidential_issues_system_notes.png
diff --git a/doc/workflow/README.md b/doc/workflow/README.md
index b317bd79ded..a56ae75fe69 100644
--- a/doc/workflow/README.md
+++ b/doc/workflow/README.md
@@ -7,6 +7,9 @@
 - [Feature branch workflow](workflow.md)
 - [GitLab Flow](gitlab_flow.md)
 - [Groups](groups.md)
+- Issues - The GitLab Issue Tracker is an advanced and complete tool for
+  tracking the evolution of a new idea or the process of solving a problem.
+  - [Confidential issues](../user/project/issues/confidential_issues.md)
 - [Issue Board](../user/project/issue_board.md)
 - [Keyboard shortcuts](shortcuts.md)
 - [File finder](file_finder.md)