patch 9.0.2123: Problem with initializing the length of range() lists Commit: https://github.com/vim/vim/commit/df63da98d8dc284b1c76cfe1b17fa0acbd6094d8 Author: Christian Brabandt <cb@256bit.org> Date: Thu Nov 23 20:14:28 2023 +0100 patch 9.0.2123: Problem with initializing the length of range() lists Problem: Problem with initializing the length of range() lists Solution: Set length explicitly when it shouldn't contain any items range() may cause a wrong calculation of list length, which may later then cause a segfault in list_find(). This is usually not a problem, because range_list_materialize() calculates the length, when it materializes the list. In addition, in list_find() when the length of the range was wrongly initialized, it may seem to be valid, so the check for list index out-of-bounds will not be true, because it is called before the list is actually materialized. And so we may eventually try to access a null pointer, causing a segfault. So this patch does 3 things: - In f_range(), when we know that the list should be empty, explicitly set the list->lv_len value to zero. This should happen, when start is larger than end (in case the stride is positive) or end is larger than start when the stride is negative. This should fix the underlying issue properly. However, - as a safety measure, let's check that the requested index is not out of range one more time, after the list has been materialized and return NULL in case it suddenly is. - add a few more tests to verify the behaviour. fixes: #13557 closes: #13563 Co-authored-by: Tim Pope <tpope@github.com> Signed-off-by: Christian Brabandt <cb@256bit.org>

" Common preparations for running tests.

" Only load this once.
if 1

  " When using xterm version 377 the response to the modifyOtherKeys status
  " interferes with some tests.  Remove the request from the t_TI termcap
  " entry.
  let &t_TI = substitute(&t_TI, "\<Esc>\\[?4m", '', '')

  if exists('s:did_load')
    finish
  endif
  let s:did_load = 1
endif

" Make sure 'runtimepath' and 'packpath' does not include $HOME.
set rtp=$VIM/vimfiles,$VIMRUNTIME,$VIM/vimfiles/after
if has('packages')
  let &packpath = &rtp
endif

" Only when the +eval feature is present.
if 1
  " Make sure the .Xauthority file can be found after changing $HOME.
  if $XAUTHORITY == ''
    let $XAUTHORITY = $HOME . '/.Xauthority'
  endif

  " Avoid storing shell history.
  let $HISTFILE = ""

  " Have current $HOME available as $ORIGHOME.  $HOME is used for option
  " defaults before we get here, and test_mksession checks that.
  let $ORIGHOME = $HOME

  " Make sure $HOME does not get read or written.
  " It must exist, gnome tries to create $HOME/.gnome2
  let $HOME = getcwd() . '/XfakeHOME'
  if !isdirectory($HOME)
    call mkdir($HOME)
  endif
endif