commit d5cec1f1f055316c353cfa15ad8d5eb0952d50a0
author =?UTF-8?q?Dundar=20G=C3=B6c?= <gocdundar@gmail.com> Sat Jan 29 15:19:23 2022 +0000
committer Bram Moolenaar <Bram@vim.org> Sat Jan 29 15:19:23 2022 +0000
tree 94d3ad44783e3442be7293edb3d5890ac08f0377
parent f12b7815f6b55c3e2f37366aa45e723b1fcb2e9a

patch 8.2.4255: theoretical computation overflow

Problem:    Theoretical computation overflow.
Solution:   Perform multiplication in a wider type. (closes #9657)

src/memline.c

diff --git a/src/memline.c b/src/memline.c
index 06fd97c..c18109a 100644
--- a/src/memline.c
+++ b/src/memline.c
@@ -5778,7 +5778,7 @@
 	     && lnum >= curline + buf->b_ml.ml_chunksize[curix].mlcs_numlines)
 		|| (offset != 0
 	       && offset > size + buf->b_ml.ml_chunksize[curix].mlcs_totalsize
-		      + ffdos * buf->b_ml.ml_chunksize[curix].mlcs_numlines)))
+		 + (long)ffdos * buf->b_ml.ml_chunksize[curix].mlcs_numlines)))
     {
 	curline += buf->b_ml.ml_chunksize[curix].mlcs_numlines;
 	size += buf->b_ml.ml_chunksize[curix].mlcs_totalsize;