vim-patch:9.2.0385: Integer overflow with "ze" and large 'sidescrolloff' (#39289)

Problem:  Integer overflow with "ze" and large 'sidescrolloff'.
Solution: Check for overflow to avoid negative w_leftcol (zeertzjq).

closes: vim/vim#20026

https://github.com/vim/vim/commit/33f3965087b01dccf4382ed419d34799ffd66cd9

2 files changed, 5 insertions, 5 deletions

diff --git a/src/nvim/move.c b/src/nvim/move.c
index 2354e77902..a1ef9634d2 100644
--- a/src/nvim/move.c
+++ b/src/nvim/move.c
@@ -885,9 +885,8 @@ void curs_columns(win_T *wp, int may_scroll)
     // If scrolling is off, wp->w_leftcol is assumed to be 0
 
     // If Cursor is left of the screen, scroll rightwards.
-    // If Cursor is right of the screen, scroll leftwards
-    // If we get closer to the edge than 'sidescrolloff', scroll a little
-    // extra
+    // If Cursor is right of the screen, scroll leftwards.
+    // If we get closer to the edge than 'sidescrolloff', scroll a little extra.
     int64_t siso = get_sidescrolloff_value(wp);
     int64_t off_left = startcol - wp->w_leftcol - siso;
     int64_t off_right = endcol - wp->w_leftcol - (wp->w_view_width - siso) + 1;
diff --git a/src/nvim/normal.c b/src/nvim/normal.c
index 7a5a238df2..49ffd6ed2c 100644
--- a/src/nvim/normal.c
+++ b/src/nvim/normal.c
@@ -2912,9 +2912,10 @@ static void nv_zet(cmdarg_T *cap)
       int n = curwin->w_view_width - win_col_off(curwin);
       if (col + siso < n) {
         col = 0;
-      } else {
-        // TODO(zeertzjq): check for overflow
+      } else if (siso - n < INT_MAX - col) {
         col = (int)(col + siso - n + 1);
+      } else {
+        col = INT_MAX;
       }
       if (curwin->w_leftcol != col) {
         curwin->w_leftcol = col;