From 58f9befca1fa172068effad7f2ea5a9d6a7b0cca Mon Sep 17 00:00:00 2001
From: Christian Brabandt <cb@256bit.org>
Date: Tue, 14 Nov 2023 21:02:30 +0100
Subject: [PATCH] patch 9.0.2109: [security]: overflow in nv_z_get_count

Problem:  [security]: overflow in nv_z_get_count
Solution: break out, if count is too large

When getting the count for a normal z command, it may overflow for large
counts given. So verify, that we can safely store the result in a long.

Signed-off-by: Christian Brabandt <cb@256bit.org>
---
 src/normal.c                | 7 +++++++
 src/testdir/test_normal.vim | 5 +++++
 2 files changed, 12 insertions(+)

diff --git a/src/normal.c b/src/normal.c
index a06d61e6fce7d..16b4b45069329 100644
--- a/src/normal.c
+++ b/src/normal.c
@@ -2567,7 +2567,14 @@ nv_z_get_count(cmdarg_T *cap, int *nchar_arg)
 	if (nchar == K_DEL || nchar == K_KDEL)
 	    n /= 10;
 	else if (VIM_ISDIGIT(nchar))
+	{
+	    if (n > LONG_MAX / 10)
+	    {
+		clearopbeep(cap->oap);
+		break;
+	    }
 	    n = n * 10 + (nchar - '0');
+	}
 	else if (nchar == CAR)
 	{
 #ifdef FEAT_GUI
diff --git a/src/testdir/test_normal.vim b/src/testdir/test_normal.vim
index c7d37f066f208..6b889f46b3dd7 100644
--- a/src/testdir/test_normal.vim
+++ b/src/testdir/test_normal.vim
@@ -3757,4 +3757,9 @@ func Test_normal33_g_cmd_nonblank()
   bwipe!
 endfunc
 
+func Test_normal34_zet_large()
+  " shouldn't cause overflow
+  norm! z9765405999999999999
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab
