From: Eli Zaretskii <eliz@gnu.org>
Date: Fri, 21 Apr 2017 08:10:14 +0000 (+0300)
Subject: Avoid infinite loop in redisplay when header-line-format is invalid
X-Git-Tag: emacs-26.0.90~521^2~583
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=72d7961d678f9c5f4cb812e0bb9b6dffafb47c68;p=emacs.git

Avoid infinite loop in redisplay when header-line-format is invalid

* src/xdisp.c (handle_invisible_prop): Avoid inflooping when the
string has an invalid %-construct in it and is displayed as part
of mode-line or header-line.  (Bug#26586)
---

diff --git a/src/xdisp.c b/src/xdisp.c
index 58b5ca2f018..3e6a3078cea 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -4318,7 +4318,8 @@ handle_invisible_prop (struct it *it)
 		      bidi_move_to_visually_next (&it->bidi_it);
 		    }
 		  while (oldpos <= it->bidi_it.charpos
-			 && it->bidi_it.charpos < endpos);
+			 && it->bidi_it.charpos < endpos
+			 && it->bidi_it.charpos < it->bidi_it.string.schars);
 
 		  IT_STRING_CHARPOS (*it) = it->bidi_it.charpos;
 		  IT_STRING_BYTEPOS (*it) = it->bidi_it.bytepos;