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
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/testdir/test_crash.vim b/src/testdir/test_crash.vim
index fd786e5..29061aa 100644
--- a/src/testdir/test_crash.vim
+++ b/src/testdir/test_crash.vim
@@ -190,6 +190,12 @@
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!