From: Richard M. Stallman <rms@gnu.org>
Date: Mon, 27 Nov 1995 03:03:33 +0000 (+0000)
Subject: (decode_mode_spec): For p and P, avoid overflow with large buffer sizes.
X-Git-Tag: emacs-19.34~2205
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=3c7d31b921c1f532f0c2ff6b97a1cb9c93617dbf;p=emacs.git

(decode_mode_spec): For p and P, avoid overflow with large buffer sizes.
---

diff --git a/src/xdisp.c b/src/xdisp.c
index a1b5a2ea88f..86836714dcf 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -3790,7 +3790,11 @@ decode_mode_spec (w, c, spec_width, maxwidth)
 	  return "Top";
 	else
 	  {
-	    total = ((pos - BUF_BEGV (b)) * 100 + total - 1) / total;
+	    if (total > 1000000)
+	      /* Do it differently for a large value, to avoid overflow.  */
+	      total = ((pos - BUF_BEGV (b)) + (total / 100) - 1) / (total / 100);
+	    else
+	      total = ((pos - BUF_BEGV (b)) * 100 + total - 1) / total;
 	    /* We can't normally display a 3-digit number,
 	       so get us a 2-digit number that is close.  */
 	    if (total == 100)
@@ -3816,7 +3820,11 @@ decode_mode_spec (w, c, spec_width, maxwidth)
 	  }
 	else
 	  {
-	    total = ((botpos - BUF_BEGV (b)) * 100 + total - 1) / total;
+	    if (total > 1000000)
+	      /* Do it differently for a large value, to avoid overflow.  */
+	      total = ((botpos - BUF_BEGV (b)) + (total / 100) - 1) / (total / 100);
+	    else
+	      total = ((botpos - BUF_BEGV (b)) * 100 + total - 1) / total;
 	    /* We can't normally display a 3-digit number,
 	       so get us a 2-digit number that is close.  */
 	    if (total == 100)