Mercurial > vim

view src/testdir/test_backspace_opt.vim @ 33811:06219b3bdaf3 v9.0.2121

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
patch 9.0.2121: [security]: use-after-free in ex_substitute Commit: https://github.com/vim/vim/commit/26c11c56888d01e298cd8044caf860f3c26f57bb Author: Christian Brabandt <cb@256bit.org> Date: Wed Nov 22 21:26:41 2023 +0100 patch 9.0.2121: [security]: use-after-free in ex_substitute Problem: [security]: use-after-free in ex_substitute Solution: always allocate memory closes: #13552 A recursive :substitute command could cause a heap-use-after free in Vim (CVE-2023-48706). The whole reproducible test is a bit tricky, I can only reproduce this reliably when no previous substitution command has been used yet (which is the reason, the test needs to run as first one in the test_substitute.vim file) and as a combination of the `:~` command together with a :s command that contains the special substitution atom `~\=` which will make use of a sub-replace special atom and calls a vim script function. There was a comment in the existing :s code, that already makes the `sub` variable allocate memory so that a recursive :s call won't be able to cause any issues here, so this was known as a potential problem already. But for the current test-case that one does not work, because the substitution does not start with `\=` but with `~\=` (and since there does not yet exist a previous substitution atom, Vim will simply increment the `sub` pointer (which then was not allocated dynamically) and later one happily use a sub-replace special expression (which could then free the `sub` var). The following commit fixes this, by making the sub var always using allocated memory, which also means we need to free the pointer whenever we leave the function. Since sub is now always an allocated variable, we also do no longer need the sub_copy variable anymore, since this one was used to indicated when sub pointed to allocated memory (and had therefore to be freed on exit) and when not. Github Security Advisory: https://github.com/vim/vim/security/advisories/GHSA-c8qm-x72m-q53q Signed-off-by: Christian Brabandt <cb@256bit.org>
author Christian Brabandt <cb@256bit.org>
date Wed, 22 Nov 2023 22:15:05 +0100
parents e7ab58f57ea3
children
line wrap: on
line source

" Tests for 'backspace' settings

func Test_backspace_option()
  set backspace=
  call assert_equal('', &backspace)
  set backspace=indent
  call assert_equal('indent', &backspace)
  set backspace=eol
  call assert_equal('eol', &backspace)
  set backspace=start
  call assert_equal('start', &backspace)
  set backspace=nostop
  call assert_equal('nostop', &backspace)
  " Add the value
  set backspace=
  set backspace=indent
  call assert_equal('indent', &backspace)
  set backspace+=eol
  call assert_equal('indent,eol', &backspace)
  set backspace+=start
  call assert_equal('indent,eol,start', &backspace)
  set backspace+=nostop
  call assert_equal('indent,eol,start,nostop', &backspace)
  " Delete the value
  set backspace-=nostop
  call assert_equal('indent,eol,start', &backspace)
  set backspace-=indent
  call assert_equal('eol,start', &backspace)
  set backspace-=start
  call assert_equal('eol', &backspace)
  set backspace-=eol
  call assert_equal('', &backspace)
  " Check the error
  call assert_fails('set backspace=ABC', 'E474:')
  call assert_fails('set backspace+=def', 'E474:')
  " NOTE: Vim doesn't check following error...
  "call assert_fails('set backspace-=ghi', 'E474:')

  " Check backwards compatibility with version 5.4 and earlier
  set backspace=0
  call assert_equal('0', &backspace)
  set backspace=1
  call assert_equal('1', &backspace)
  set backspace=2
  call assert_equal('2', &backspace)
  set backspace=3
  call assert_equal('3', &backspace)
  call assert_fails('set backspace=4', 'E474:')
  call assert_fails('set backspace=10', 'E474:')

  " Cleared when 'compatible' is set
  set compatible
  call assert_equal('', &backspace)
  set nocompatible viminfo+=nviminfo
endfunc

" Test with backspace set to the non-compatible setting
func Test_backspace_ctrl_u()
  new
  call append(0,  [
        \ "1 this shouldn't be deleted",
        \ "2 this shouldn't be deleted",
        \ "3 this shouldn't be deleted",
        \ "4 this should be deleted",
        \ "5 this shouldn't be deleted",
        \ "6 this shouldn't be deleted",
        \ "7 this shouldn't be deleted",
        \ "8 this shouldn't be deleted (not touched yet)"])
  call cursor(2, 1)

  set compatible
  set backspace=2

  exe "normal Avim1\<C-U>\<Esc>\<CR>"
  exe "normal Avim2\<C-G>u\<C-U>\<Esc>\<CR>"

  set cpo-=<
  inoremap <c-u> <left><c-u>
  exe "normal Avim3\<*C-U>\<Esc>\<CR>"
  iunmap <c-u>
  exe "normal Avim4\<C-U>\<C-U>\<Esc>\<CR>"

  " Test with backspace set to the compatible setting
  set backspace= visualbell
  exe "normal A vim5\<Esc>A\<C-U>\<C-U>\<Esc>\<CR>"
  exe "normal A vim6\<Esc>Azwei\<C-G>u\<C-U>\<Esc>\<CR>"

  inoremap <c-u> <left><c-u>
  exe "normal A vim7\<*C-U>\<*C-U>\<Esc>\<CR>"

  call assert_equal([
        \ "1 this shouldn't be deleted",
        \ "2 this shouldn't be deleted",
        \ "3 this shouldn't be deleted",
        \ "4 this should be deleted3",
        \ "",
        \ "6 this shouldn't be deleted vim5",
        \ "7 this shouldn't be deleted vim6",
        \ "8 this shouldn't be deleted (not touched yet) vim7",
        \ ""], getline(1, '$'))

  " Reset values
  set compatible&vim
  set visualbell&vim
  set backspace&vim

  " Test new nostop option
  %d_
  let expected = "foo bar foobar"
  call setline(1, expected)
  call cursor(1, 8)
  exe ":norm! ianotherone\<c-u>"
  call assert_equal(expected, getline(1))
  call cursor(1, 8)
  exe ":norm! ianothertwo\<c-w>"
  call assert_equal(expected, getline(1))

  let content = getline(1)
  for value in ['indent,nostop', 'eol,nostop', 'indent,eol,nostop', 'indent,eol,start,nostop']
    exe ":set bs=".. value
    %d _
    call setline(1, content)
    let expected = " foobar"
    call cursor(1, 8)
    exe ":norm! ianotherone\<c-u>"
    call assert_equal(expected, getline(1), 'CTRL-U backspace value: '.. &bs)
    let expected = "foo  foobar"
    call setline(1, content)
    call cursor(1, 8)
    exe ":norm! ianothertwo\<c-w>"
    call assert_equal(expected, getline(1), 'CTRL-W backspace value: '.. &bs)
  endfor

  " Reset options
  set compatible&vim
  set visualbell&vim
  set backspace&vim
  close!
endfunc

" Test for setting 'backspace' to a number value (for backward compatibility)
func Test_backspace_number_value()
  new

  set backspace=0
  call setline(1, ['one two', 'three four'])
  call cursor(2, 1)
  exe "normal! A\<C-W>\<C-U>"
  call assert_equal('three four', getline(2))

  set backspace=1
  exe "normal! A\<CR>five\<C-W>\<C-U>\<C-W>\<C-U>"
  call assert_equal(['one two', 'three four'], getline(1, '$'))

  set backspace=2
  call cursor(2, 7)
  exe "normal! ihalf\<C-U>"
  call assert_equal('three four', getline(2))

  set backspace=3
  call cursor(2, 7)
  exe "normal! ihalf\<C-U>"
  call assert_equal('four', getline(2))

  bw!
  set backspace&
endfunc

" vim: shiftwidth=2 sts=2 expandtab