process:username: metric for errors

Add two metrics: - process_metadata_username_ignored_not_in_host_namespaces: This is to note that we did not perform uid->username resolution and it was ignored due the target process not being in mount or user host namespaces. - process_metadata_username_failed: that is to note that we did try to resolve target process uid->username but it failed for some reasons. Signed-off-by: Djalal Harouni <[email protected]>
cilium · Jun 24, 2024 · 745f46b · 745f46b
1 parent 1775eb6
commit 745f46b
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Showing 3 changed files with 25 additions and 11 deletions.
diff --git a/docs/content/en/docs/reference/metrics.md b/docs/content/en/docs/reference/metrics.md
diff --git a/pkg/metrics/errormetrics/errormetrics.go b/pkg/metrics/errormetrics/errormetrics.go
@@ -28,16 +28,23 @@ const (
 	HandlerError
 	// An event finalizer on Process failed
 	EventFinalizeProcessInfoFailed
+	// Failed to resolve Process uid to username
+	ProcessMetadataUsernameFailed
+	// The username resolution was skipped since the process is not in host
+	// namespaces.
+	ProcessMetadataUsernameIgnoredNotInHost
 )
 
 var errorTypeLabelValues = map[ErrorType]string{
-	ProcessCacheMissOnGet:          "process_cache_miss_on_get",
-	ProcessCacheEvicted:            "process_cache_evicted",
-	ProcessCacheMissOnRemove:       "process_cache_miss_on_remove",
-	ProcessPidTidMismatch:          "process_pid_tid_mismatch",
-	EventMissingProcessInfo:        "event_missing_process_info",
-	HandlerError:                   "handler_error",
-	EventFinalizeProcessInfoFailed: "event_finalize_process_info_failed",
+	ProcessCacheMissOnGet:                   "process_cache_miss_on_get",
+	ProcessCacheEvicted:                     "process_cache_evicted",
+	ProcessCacheMissOnRemove:                "process_cache_miss_on_remove",
+	ProcessPidTidMismatch:                   "process_pid_tid_mismatch",
+	EventMissingProcessInfo:                 "event_missing_process_info",
+	HandlerError:                            "handler_error",
+	EventFinalizeProcessInfoFailed:          "event_finalize_process_info_failed",
+	ProcessMetadataUsernameFailed:           "process_metadata_username_failed",
+	ProcessMetadataUsernameIgnoredNotInHost: "process_metadata_username_ignored_not_in_host_namespaces",
 }
 
 func (e ErrorType) String() string {

diff --git a/pkg/sensors/exec/userinfo/userinfo.go b/pkg/sensors/exec/userinfo/userinfo.go
@@ -8,6 +8,7 @@ import (
 
 	"github.com/cilium/tetragon/pkg/api/processapi"
 	"github.com/cilium/tetragon/pkg/grpc/exec"
+	"github.com/cilium/tetragon/pkg/metrics/errormetrics"
 	"github.com/cilium/tetragon/pkg/option"
 	"github.com/cilium/tetragon/pkg/reader/namespace"
 	"github.com/cilium/tetragon/pkg/reader/userdb"
@@ -36,11 +37,17 @@ func getAccountUnix(uid uint32, ns *processapi.MsgNamespaces) (string, error) {
 func MsgToExecveAccountUnix(m *exec.MsgExecveEventUnix) error {
 	if option.Config.UsernameMetadata == int(option.USERNAME_METADATA_UNIX) {
 		username, err := getAccountUnix(m.Unix.Process.UID, &m.Unix.Msg.Namespaces)
-		if err != nil {
-			return err
+		if err == nil {
+			m.Unix.Process.User.Name = username
+			return nil
 		}
 
-		m.Unix.Process.User.Name = username
+		if errors.Is(err, ErrNotInHostNs) {
+			errormetrics.ErrorTotalInc(errormetrics.ProcessMetadataUsernameIgnoredNotInHost)
+		} else {
+			errormetrics.ErrorTotalInc(errormetrics.ProcessMetadataUsernameFailed)
+		}
+		return err
 	}
 	return nil
 }