Deploy Keys gets restricted after blocking user

Summary

A Deploy Key, which has been added by a user that is blocked afterwards is no longer usable for pushes, while cloning is still possible.

Steps to reproduce

  1. Create a default user
  2. Create a shared private group
  3. Create a shared private project
  4. Generate a fresh ssh-key and add this key to a project as a deployment key with permissions set correctly
  5. Clone the project, fill it locally with a sample file and push that change back --> this is expected to be working correctly
  6. Block the user using an administrative account
  7. Try to push changes to this repository --> this fails for us
  8. Try to freshly clone this repository using the same key --> this works - while it is not clear, why cloning is OK, but pushing is NOT.

What is the current bug behavior?

Writing to a repository gets denied, when a deployment key has been added by a user that is blocked

matthias@w-workwmlin:~/shareproject$ git push
Enumerating objects: 4, done.
Counting objects: 100% (4/4), done.
Delta compression using up to 2 threads
Compressing objects: 100% (2/2), done.
Writing objects: 100% (3/3), 284 bytes | 284.00 KiB/s, done.
Total 3 (delta 0), reused 0 (delta 0)
remote: GitLab: You are not allowed to push code to this project.
To code.no-cloud.io:sharegroup/shareproject.git
 ! [remote rejected] master -> master (pre-receive hook declined)
error: failed to push some refs to 'git@code.no-cloud.io:sharegroup/shareproject

matthias@w-workwmlin:~$ mv shareproject shareproject2

matthias@w-workwmlin:~$ git clone git@code.no-cloud.io:sharegroup/shareproject.g
Cloning into 'shareproject'...
remote: Enumerating objects: 3, done.
remote: Counting objects: 100% (3/3), done.
remote: Total 3 (delta 0), reused 0 (delta 0), pack-reused 0
Receiving objects: 100% (3/3), done.

What is the expected correct behavior?

Either everything is impossible after the user has been blocked (cloning and writing to a repo) or none - while the use of a deployment key is in our case to prevent the crash of all CI/CD lines when a user leaves the company

Output of checks

This bug happens on on-premise installations - to be verified for cloud solutions

Results of GitLab environment info

Tested with 13.10.3 and 13.10.1

Expand for output related to GitLab environment info 

(For installations with omnibus-gitlab package run and paste the output of:
`sudo gitlab-rake gitlab:env:info`)

```
root@code:/# gitlab-rake gitlab:env:info

System information
System:
Current User:   git
Using RVM:      no
Ruby Version:   2.7.2p137
Gem Version:    3.1.4
Bundler Version:2.1.4
Rake Version:   13.0.3
Redis Version:  6.0.10
Git Version:    2.29.0
Sidekiq Version:5.2.9
Go Version:     unknown

GitLab information
Version:        13.10.3
Revision:       b1774ad36a9
Directory:      /opt/gitlab/embedded/service/gitlab-rails
DB Adapter:     PostgreSQL
DB Version:     12.6
URL:            https://code.no-cloud.io
HTTP Clone URL: https://code.no-cloud.io/some-group/some-project.git
SSH Clone URL:  git@code.no-cloud.io:some-group/some-project.git
Using LDAP:     yes
Using Omniauth: yes
Omniauth Providers:

GitLab Shell
Version:        13.17.0
Repository storage paths:
- default:      /var/opt/gitlab/git-data/repositories
GitLab Shell path:              /opt/gitlab/embedded/service/gitlab-shell
Git:            /opt/gitlab/embedded/bin/git
```

Results of GitLab application Check

run on the 13.10.3 system - a docker setup:

Expand for output related to the GitLab application check 
(For installations with omnibus-gitlab package run and paste the output of:
sudo gitlab-rake gitlab:check SANITIZE=true)




root@code:/# gitlab-rake gitlab:check SANITIZE=true
Checking GitLab subtasks ...

Checking GitLab Shell ...

GitLab Shell: ... GitLab Shell version >= 13.17.0 ? ... OK (13.17.0)
Running /opt/gitlab/embedded/service/gitlab-shell/bin/check
Internal API available: OK
Redis available via internal API: OK
gitlab-shell self-check successful

Checking GitLab Shell ... Finished

Checking Gitaly ...

Gitaly: ... default ... OK

Checking Gitaly ... Finished

Checking Sidekiq ...

Sidekiq: ... Running? ... yes
Number of Sidekiq processes (cluster/worker) ... 1/1

Checking Sidekiq ... Finished

Checking Incoming Email ...

Incoming Email: ... Reply by email is disabled in config/gitlab.yml

Checking Incoming Email ... Finished

Checking LDAP ...

LDAP: ... Server: ldapmain
LDAP authentication... Success
LDAP users with access to your GitLab server (only showing the first 100 results)
        User output sanitized. Found 11 users of 100 limit.

Checking LDAP ... Finished

Checking GitLab App ...

Git configured correctly? ... yes
Database config exists? ... yes
All migrations up? ... yes
Database contains orphaned GroupMembers? ... no
GitLab config exists? ... yes
GitLab config up to date? ... yes
Log directory writable? ... yes
Tmp directory writable? ... yes
Uploads directory exists? ... yes
Uploads directory has correct permissions? ... yes
Uploads directory tmp has correct permissions? ... yes
Init script exists? ... skipped (omnibus-gitlab has no init script)
Init script up-to-date? ... skipped (omnibus-gitlab has no init script)
Projects have namespace: ...
2/1 ... yes
2/2 ... yes
2/3 ... yes
2/4 ... yes
2/5 ... yes
2/6 ... yes
4/8 ... yes
4/9 ... yes
4/10 ... yes
4/11 ... yes
4/12 ... yes
4/13 ... yes
4/14 ... yes
4/15 ... yes
4/16 ... yes
4/17 ... yes
3/18 ... yes
3/19 ... yes
3/20 ... yes
3/21 ... yes
3/22 ... yes
3/23 ... yes
3/24 ... yes
3/25 ... yes
3/26 ... yes
3/27 ... yes
3/28 ... yes
3/29 ... yes
3/30 ... yes
3/31 ... yes
3/32 ... yes
5/33 ... yes
10/34 ... yes
13/35 ... yes
13/36 ... yes
13/37 ... yes
14/38 ... yes
47/39 ... yes
47/41 ... yes
47/42 ... yes
47/43 ... yes
15/44 ... yes
13/45 ... yes
47/46 ... yes
16/48 ... yes
16/49 ... yes
16/50 ... yes
16/51 ... yes
16/52 ... yes
17/53 ... yes
17/54 ... yes
17/55 ... yes
18/56 ... yes
19/57 ... yes
20/58 ... yes
20/59 ... yes
20/60 ... yes
20/61 ... yes
20/62 ... yes
20/63 ... yes
20/64 ... yes
22/66 ... yes
23/67 ... yes
40/68 ... yes
41/69 ... yes
39/70 ... yes
42/71 ... yes
25/72 ... yes
25/73 ... yes
25/74 ... yes
25/75 ... yes
25/76 ... yes
25/77 ... yes
25/78 ... yes
25/79 ... yes
25/80 ... yes
26/81 ... yes
26/82 ... yes
26/83 ... yes
26/84 ... yes
27/85 ... yes
27/86 ... yes
27/87 ... yes
28/88 ... yes
29/89 ... yes
30/91 ... yes
15/95 ... yes
33/96 ... yes
15/97 ... yes
34/98 ... yes
34/99 ... yes
34/100 ... yes
35/102 ... yes
35/103 ... yes
35/104 ... yes
43/105 ... yes
24/108 ... yes
8/109 ... yes
48/112 ... yes
50/113 ... yes
8/116 ... yes
54/117 ... yes
48/120 ... yes
48/122 ... yes
48/123 ... yes
48/124 ... yes
48/125 ... yes
48/127 ... yes
55/128 ... yes
32/129 ... yes
48/130 ... yes
32/131 ... yes
23/132 ... yes
24/133 ... yes
47/135 ... yes
56/136 ... yes
47/137 ... yes
15/138 ... yes
8/139 ... yes
8/140 ... yes
58/141 ... yes
59/143 ... yes
59/144 ... yes
60/145 ... yes
59/146 ... yes
56/147 ... yes
8/148 ... yes
62/149 ... yes
47/150 ... yes
8/151 ... yes
63/152 ... yes
61/153 ... yes
8/154 ... yes
66/155 ... yes
26/156 ... yes
61/157 ... yes
67/158 ... yes
67/159 ... yes
42/160 ... yes
8/161 ... yes
55/162 ... yes
8/163 ... yes
83/164 ... yes
84/165 ... yes
84/166 ... yes
35/167 ... yes
84/168 ... yes
2/169 ... yes
86/170 ... yes
Redis version >= 4.0.0? ... yes
Ruby version >= 2.7.2 ? ... yes (2.7.2)
Git version >= 2.29.0 ? ... yes (2.29.0)
Git user has default SSH configuration? ... yes
Active users: ... 11
Is authorized keys file accessible? ... yes
GitLab configured to store new projects in hashed storage? ... yes
All projects are in hashed storage? ... yes

Checking GitLab App ... Finished


Checking GitLab subtasks ... Finished
Edited by Matthias R. Wiora