commit 7cc96923c44bbcc541cbd211b6308d87a965f0c3
author Bram Moolenaar <Bram@vim.org> Fri Jan 31 22:41:38 2020 +0100
committer Bram Moolenaar <Bram@vim.org> Fri Jan 31 22:41:38 2020 +0100
tree 19061800642c9fdffb808ee1b08a8d3b9cd0f7bd
parent 7f829cab356d63b8e59559285593777a66bcc02b

patch 8.2.0189: cd() with NULL argument crashes

Problem:    cd() with NULL argument crashes.
Solution:   Check for NULL. (Ken Takata, closes #5558)

src/ex_docmd.c

diff --git a/src/ex_docmd.c b/src/ex_docmd.c
index 6df6975..80cc930 100644
--- a/src/ex_docmd.c
+++ b/src/ex_docmd.c
@@ -6572,7 +6572,7 @@
     int		dir_differs;
     int		retval = FALSE;
 
-    if (allbuf_locked())
+    if (new_dir == NULL || allbuf_locked())
 	return FALSE;
 
     if (vim_strchr(p_cpo, CPO_CHDIR) != NULL && curbufIsChanged() && !forceit)

src/testdir/test_cd.vim

diff --git a/src/testdir/test_cd.vim b/src/testdir/test_cd.vim
index 05d3877..e44b25f 100644
--- a/src/testdir/test_cd.vim
+++ b/src/testdir/test_cd.vim
@@ -101,6 +101,8 @@
   call assert_fails("call chdir('dir-abcd')", 'E472:')
   silent! let d = chdir("dir_abcd")
   call assert_equal("", d)
+  " Should not crash
+  call chdir(d)
 
   only | tabonly
   call chdir(topdir)

src/version.c

diff --git a/src/version.c b/src/version.c
index 9a3d42f..5f090c3 100644
--- a/src/version.c
+++ b/src/version.c
@@ -743,6 +743,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    189,
+/**/
     188,
 /**/
     187,