neovim

commit 6af359ef4cc3c221e0e3102ab2b54cf64d7c9835
parent a4bec30b7b2fa66a2db9d03f54e51dff58116465
Author: zeertzjq <zeertzjq@outlook.com>
Date:   Fri,  2 Aug 2024 06:00:02 +0800

vim-patch:9.1.0647: [security] use-after-free in tagstack_clear_entry

Problem:  [security] use-after-free in tagstack_clear_entry
          (Suyue Guo )
Solution: Instead of manually calling vim_free() on each of the tagstack
          entries, let's use tagstack_clear_entry(), which will
          also free the stack, but using the VIM_CLEAR macro,
          which prevents a use-after-free by setting those pointers
          to NULL

This addresses CVE-2024-41957

Github advisory:
https://github.com/vim/vim/security/advisories/GHSA-f9cr-gv85-hcr4

https://github.com/vim/vim/commit/8a0bbe7b8aad6f8da28dee218c01bc8a0185a2d5

Co-authored-by: Christian Brabandt <cb@256bit.org>

Diffstat:
M
src/nvim/window.c
 | 
4
++--
M
test/functional/legacy/crash_spec.lua
 | 
19
+++++++++++++++++++
A
test/old/testdir/crash/double_free
 | 
0

M
test/old/testdir/test_crash.vim
 | 
6
++++++

4 files changed, 27 insertions(+), 2 deletions(-)
diff --git a/src/nvim/window.c b/src/nvim/window.c
@@ -73,6 +73,7 @@
 #include "nvim/statusline.h"
 #include "nvim/strings.h"
 #include "nvim/syntax.h"
+#include "nvim/tag.h"
 #include "nvim/terminal.h"
 #include "nvim/types_defs.h"
 #include "nvim/ui.h"
@@ -5205,8 +5206,7 @@ void win_free(win_T *wp, tabpage_T *tp)
   xfree(wp->w_lines);
 
   for (int i = 0; i < wp->w_tagstacklen; i++) {
-    xfree(wp->w_tagstack[i].tagname);
-    xfree(wp->w_tagstack[i].user_data);
+    tagstack_clear_entry(&wp->w_tagstack[i]);
   }
 
   xfree(wp->w_localdir);
diff --git a/test/functional/legacy/crash_spec.lua b/test/functional/legacy/crash_spec.lua
@@ -1,8 +1,12 @@
+local t = require('test.testutil')
 local n = require('test.functional.testnvim')()
 
 local assert_alive = n.assert_alive
 local clear = n.clear
 local command = n.command
+local eq = t.eq
+local eval = n.eval
+local exec = n.exec
 local feed = n.feed
 
 before_each(clear)
@@ -32,3 +36,18 @@ it('no crash with very long option error message', function()
   pcall(command, 'source test/old/testdir/crash/poc_did_set_langmap')
   assert_alive()
 end)
+
+it('no crash when closing window with tag in loclist', function()
+  exec([[
+    new
+    lexpr ['foo']
+    lopen
+    let g:qf_bufnr = bufnr()
+    lclose
+    call settagstack(1, #{items: [#{tagname: 'foo', from: [g:qf_bufnr, 1, 1, 0]}]})
+  ]])
+  eq(1, eval('bufexists(g:qf_bufnr)'))
+  command('1close')
+  eq(0, eval('bufexists(g:qf_bufnr)'))
+  assert_alive()
+end)
diff --git a/test/old/testdir/crash/double_free b/test/old/testdir/crash/double_free
Binary files differ.
diff --git a/test/old/testdir/test_crash.vim b/test/old/testdir/test_crash.vim
@@ -190,6 +190,12 @@ func Test_crash1_3()
   call term_sendkeys(buf, args)
   call TermWait(buf, 150)
 
+  let file = 'crash/double_free'
+  let cmn_args = "%s -u NONE -i NONE -n -e -s -S %s -c ':qa!'\<cr>"
+  let args = printf(cmn_args, vim, file)
+  call term_sendkeys(buf, args)
+  call TermWait(buf, 50)
+
   " clean up
   exe buf .. "bw!"
   bw!