diff --git a/include/linux/syslog.h b/include/linux/syslog.h
index 3891139..ce4c665 100644
--- a/include/linux/syslog.h
+++ b/include/linux/syslog.h
@@ -47,6 +47,12 @@
 #define SYSLOG_FROM_CALL 0
 #define SYSLOG_FROM_FILE 1
 
+/*
+ * Syslog priority (PRI) maximum length in char : '<[0-9]{1,3}>'
+ * See RFC5424 for details
+*/
+#define SYSLOG_PRI_MAX_LENGTH 5
+
 int do_syslog(int type, char __user *buf, int count, bool from_file);
 
 #endif /* _LINUX_SYSLOG_H */