Mercurial > vim
view src/testdir/test_tab.vim @ 33811:06219b3bdaf3 v9.0.2121
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 | 08940efa6b4e |
children |
line wrap: on
line source
" Various tests for inserting a Tab. " Tests for "r<Tab>" with 'smarttab' and 'expandtab' set/not set. " Also test that dv_ works correctly func Test_smarttab() enew! set smarttab expandtab ts=8 sw=4 " make sure that backspace works, no matter what termcap is used exe "set t_kD=\<C-V>x7f t_kb=\<C-V>x08" call append(0, ['start text', \ "\t\tsome test text", \ 'test text', \ "\t\tother test text", \ ' a cde', \ ' f ghi', \ 'test text', \ ' Second line beginning with whitespace' \ ]) call cursor(1, 1) exe "normal /some\<CR>" exe "normal r\t" call assert_equal("\t\t ome test text", getline('.')) set noexpandtab exe "normal /other\<CR>" exe "normal r\t" call assert_equal("\t\t ther test text", getline('.')) " Test replacing with Tabs and then backspacing to undo it exe "normal j0wR\t\t\t\<BS>\<BS>\<BS>" call assert_equal(" a cde", getline('.')) " Test replacing with Tabs exe "normal j0wR\t\t\t" call assert_equal(" \t\thi", getline('.')) " Test that copyindent works with expandtab set set expandtab smartindent copyindent ts=8 sw=8 sts=8 exe "normal jo{\<CR>x" call assert_equal('{', getline(line('.') - 1)) call assert_equal(' x', getline('.')) set nosol exe "normal /Second line/\<CR>" exe "normal fwdv_" call assert_equal(' with whitespace', getline('.')) enew! set expandtab& smartindent& copyindent& ts& sw& sts& endfunc func Test_softtabstop() new set sts=0 sw=0 exe "normal ix\<Tab>x\<Esc>" call assert_equal("x\tx", getline(1)) call setline(1, '') set sts=4 exe "normal ix\<Tab>x\<Esc>" call assert_equal("x x", getline(1)) call setline(1, '') set sts=-1 sw=4 exe "normal ix\<Tab>x\<Esc>" call assert_equal("x x", getline(1)) call setline(1, 'x ') set sts=0 sw=0 backspace=start exe "normal A\<BS>x\<Esc>" call assert_equal("x x", getline(1)) call setline(1, 'x ') set sts=4 exe "normal A\<BS>x\<Esc>" call assert_equal("x x", getline(1)) call setline(1, 'x ') set sts=-1 sw=4 exe "normal A\<BS>x\<Esc>" call assert_equal("x x", getline(1)) call setline(1, 'x') set sts=-1 sw=0 smarttab exe "normal I\<Tab>\<Esc>" call assert_equal("\tx", getline(1)) call setline(1, 'x') exe "normal I\<Tab>\<BS>\<Esc>" call assert_equal("x", getline(1)) set sts=0 sw=0 backspace& nosmarttab bwipe! endfunc " vim: shiftwidth=2 sts=2 expandtab