Improve regex to not trigger stack overflow

* lisp/textmodes/reftex-vars.el (reftex-label-regexps): Improve regex in
order not to trigger a stack overflow in regex matcher with unbalanced
brackets (bug#22146).

diff --git a/lisp/textmodes/reftex-vars.el b/lisp/textmodes/reftex-vars.el
index 5683e62493a914f72387efe8a813376b7bd12e22..fcab1367f7d7f49d8f1164e1d2ff9f6517832a71 100644 (file)
--- a/lisp/textmodes/reftex-vars.el
+++ b/lisp/textmodes/reftex-vars.el
@@ -877,7 +877,7 @@ DOWNCASE    t:   Downcase words before using them."
       "\\\\label{\\(?1:[^}]*\\)}"
       ;; keyvals [..., label = {foo}, ...] forms used by ctable,
       ;; listings, minted, ...
-      "\\[[^][]*\\<label[[:space:]]*=[[:space:]]*{?\\(?1:[^],}]+\\)}?")
+      "\\[[^][]\\{0,2000\\}\\<label[[:space:]]*=[[:space:]]*{?\\(?1:[^],}]+\\)}?")
     "List of regexps matching \\label definitions.
 The default value matches usual \\label{...} definitions and
 keyval style [..., label = {...}, ...] label definitions.  It is