Repository: kubernetes-sigs/security-profiles-operator (c)

Issue:
merging of SELinux policies produces duplicates
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#### What happened:
I was recording File Integrity Operator policies using the SELinux log-enricher based recorder and the resulting merged policy has a ton of duplicates:
```
spec:                                                                                                                                                                                                                                         
  allow:                                                                                                                                                                                                                                      
    NetworkManager_etc_rw_t:                                                                                                                                                                                                                  
      dir:                                                                                                                                                                                                                                    
      - read                                                                                                                                                                                                                                  
      - read                                                                                                                                                                                                                                  
      - read                                                                                                                                                                                                                                  
      - read
```

#### What you expected to happen:
no duplicates

#### How to reproduce it (as minimally and precisely as possible):
1. create a namespace, label it for recording
2. create a profile recording
3. run FIO e2e tests there
4. delete profile recording

#### Anything else we need to know?:
I used today's git HEAD, so 0.5.0 with a bunch of minor patches

#### Environment:

- Cloud provider or hardware configuration: AWS
- OS (e.g: `cat /etc/os-release`): RHCOS
- Kernel (e.g. `uname -a`): N/A
- Others: N/A


Pull request:
recordingmerger: Fix producing union of SELinux permissions
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#### What type of PR is this?
/kind bug

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/kind regression
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#### What this PR does / why we need it:
We were naively appending all permissions from the SELinux profile about
to be merged, this was causing potential duplicates. Let's check if the
permission is already present before merging it.


#### Which issue(s) this PR fixes:
Fixes #1256

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Usage: `Fixes #<issue number>`, or `Fixes (paste link of issue)`.


or

None
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#### Does this PR have test?
yes, unit tests. I also tested manually.

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#### Special notes for your reviewer:
N/A

#### Does this PR introduce a user-facing change?

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```release-note
NONE
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Patch:
diff --git a/internal/pkg/manager/recordingmerger/merge_utils.go b/internal/pkg/manager/recordingmerger/merge_utils.go
index 057279914..94fc89284 100644
--- a/internal/pkg/manager/recordingmerger/merge_utils.go
+++ b/internal/pkg/manager/recordingmerger/merge_utils.go
@@ -185,8 +185,19 @@ func addAllow(union, additional selinuxprofileapi.Allow) selinuxprofileapi.Allow
 		if _, ok := union[labelKey]; !ok {
 			union[labelKey] = make(map[selinuxprofileapi.ObjectClassKey]selinuxprofileapi.PermissionSet)
 		}
+
 		for objClass, perms := range permMap {
-			union[labelKey][objClass] = append(union[labelKey][objClass], perms...)
+			allPerms := map[string]bool{}
+			for _, havePerm := range union[labelKey][objClass] {
+				allPerms[havePerm] = true
+			}
+
+			for _, newPerm := range perms {
+				_, ok := allPerms[newPerm]
+				if !ok {
+					union[labelKey][objClass] = append(union[labelKey][objClass], newPerm)
+				}
+			}
 		}
 	}
 


Test patch:
diff --git a/internal/pkg/manager/recordingmerger/merge_utils_test.go b/internal/pkg/manager/recordingmerger/merge_utils_test.go
index f035dee17..cf8ac2276 100644
--- a/internal/pkg/manager/recordingmerger/merge_utils_test.go
+++ b/internal/pkg/manager/recordingmerger/merge_utils_test.go
@@ -153,7 +153,7 @@ func TestMergeProfiles(t *testing.T) {
 								},
 							},
 							Allow: selinuxprofileapi.Allow{
-								"label_foo": {"oc_bar2": {"do_bar2"}, "oc_baz2": {"do_baz2"}},
+								"label_foo": {"oc_bar": {"do_bar"}, "oc_bar2": {"do_bar2"}, "oc_baz2": {"do_baz2"}},
 								"label_aaa": {"oc_aaa": {"do_aaa"}, "oc_bbb": {"do_bbb"}},
 							},
 						},