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

1 files changed, 10 insertions, 2 deletions

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)