diff --git a/kernel/fail_function.c b/kernel/fail_function.c
index b0b1ad93fa95..60dc825ecc2b 100644
--- a/kernel/fail_function.c
+++ b/kernel/fail_function.c
@@ -37,9 +37,7 @@ static unsigned long adjust_error_retval(unsigned long addr, unsigned long retv)
 {
 	switch (get_injectable_error_type(addr)) {
 	case EI_ETYPE_NULL:
-		if (retv != 0)
-			return 0;
-		break;
+		return 0;
 	case EI_ETYPE_ERRNO:
 		if (retv < (unsigned long)-MAX_ERRNO)
 			return (unsigned long)-EINVAL;
@@ -48,6 +46,8 @@ static unsigned long adjust_error_retval(unsigned long addr, unsigned long retv)
 		if (retv != 0 && retv < (unsigned long)-MAX_ERRNO)
 			return (unsigned long)-EINVAL;
 		break;
+	case EI_ETYPE_TRUE:
+		return 1;
 	}
 
 	return retv;
diff --git a/lib/error-inject.c b/lib/error-inject.c
index aa63751c916f..c73651b15b76 100644
--- a/lib/error-inject.c
+++ b/lib/error-inject.c
@@ -180,6 +180,8 @@ static const char *error_type_string(int etype)
 		return "ERRNO";
 	case EI_ETYPE_ERRNO_NULL:
 		return "ERRNO_NULL";
+	case EI_ETYPE_TRUE:
+		return "TRUE";
 	default:
 		return "(unknown)";
 	}