diff --git a/tools/perf/util/sort.c b/tools/perf/util/sort.c
index 16da30d8d765..076c9d4e1ea4 100644
--- a/tools/perf/util/sort.c
+++ b/tools/perf/util/sort.c
@@ -33,6 +33,9 @@ static int repsep_snprintf(char *bf, size_t size, const char *fmt, ...)
 		}
 	}
 	va_end(ap);
+
+	if (n >= (int)size)
+		return size - 1;
 	return n;
 }