diff --git a/process/process_freebsd.go b/process/process_freebsd.go
index d87c43e8b..436dcf030 100644
--- a/process/process_freebsd.go
+++ b/process/process_freebsd.go
@@ -6,6 +6,7 @@ package process
 import (
 	"bytes"
 	"context"
+	"errors"
 	"path/filepath"
 	"strconv"
 	"strings"
@@ -329,7 +330,7 @@ func (p *Process) getKProc() (*KinfoProc, error) {
 		return nil, err
 	}
 	if length != sizeOfKinfoProc {
-		return nil, err
+		return nil, errors.New("unexpected size of KinfoProc")
 	}
 
 	k, err := parseKinfoProc(buf)
diff --git a/process/process_openbsd.go b/process/process_openbsd.go
index 76ae3e3e0..e2d0ab462 100644
--- a/process/process_openbsd.go
+++ b/process/process_openbsd.go
@@ -7,6 +7,7 @@ import (
 	"bytes"
 	"context"
 	"encoding/binary"
+	"errors"
 	"fmt"
 	"io"
 	"path/filepath"
@@ -343,7 +344,7 @@ func (p *Process) getKProc() (*KinfoProc, error) {
 		return nil, err
 	}
 	if length != sizeOfKinfoProc {
-		return nil, err
+		return nil, errors.New("unexpected size of KinfoProc")
 	}
 
 	k, err := parseKinfoProc(buf)