From 3bd61c843c69eaf9b75f4534ead065109e9bbad0 Mon Sep 17 00:00:00 2001
From: Mark Rushakoff <mark@influxdb.com>
Date: Tue, 12 Jul 2016 13:44:50 -0600
Subject: [PATCH] Detect unterminated regex when EOF reached

---
 CHANGELOG.md    | 2 ++
 tick/ast/lex.go | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index cbd2000d1..be893bf69 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,8 @@
 
 ### Bugfixes
 
+- [#710](https://github.com/influxdata/kapacitor/pull/662): Fix infinite loop when parsing unterminated regex in TICKscript.
+
 ## v1.0.0-beta3 [2016-07-09]
 
 ### Release Notes
diff --git a/tick/ast/lex.go b/tick/ast/lex.go
index 20925f9ef..de6f7795e 100644
--- a/tick/ast/lex.go
+++ b/tick/ast/lex.go
@@ -577,6 +577,8 @@ func lexRegex(l *lexer) stateFn {
 		case r == '/':
 			l.emit(TokenRegex)
 			return lexToken
+		case r == eof:
+			return l.errorf("unterminated regex")
 		default:
 			//absorb
 		}