vim/0001-patch-8.2.4977-memory-access-error-when-substitute-e.patch
Zdenek Dohnal e4ba274723 CVE-2022-1785 vim: Out-of-bounds Write
Resolves: CVE-2022-1785
2022-06-13 07:53:12 +02:00

60 lines
1.9 KiB
Diff

diff -up vim82/src/ex_cmds.c.cve1785 vim82/src/ex_cmds.c
--- vim82/src/ex_cmds.c.cve1785 2022-06-10 10:26:16.883312704 +0200
+++ vim82/src/ex_cmds.c 2022-06-10 10:26:16.910312568 +0200
@@ -4356,12 +4356,17 @@ ex_substitute(exarg_T *eap)
// Save flags for recursion. They can change for e.g.
// :s/^/\=execute("s#^##gn")
subflags_save = subflags;
+
+ // Disallow changing text or switching window in an expression.
+ ++textwinlock;
#endif
// get length of substitution part
sublen = vim_regsub_multi(&regmatch,
sub_firstlnum - regmatch.startpos[0].lnum,
sub, sub_firstline, FALSE, magic_isset(), TRUE);
#ifdef FEAT_EVAL
+ --textwinlock;
+
// If getting the substitute string caused an error, don't do
// the replacement.
// Don't keep flags set by a recursive call.
@@ -4462,9 +4467,15 @@ ex_substitute(exarg_T *eap)
mch_memmove(new_end, sub_firstline + copycol, (size_t)copy_len);
new_end += copy_len;
+#ifdef FEAT_EVAL
+ ++textwinlock;
+#endif
(void)vim_regsub_multi(&regmatch,
sub_firstlnum - regmatch.startpos[0].lnum,
sub, new_end, TRUE, magic_isset(), TRUE);
+#ifdef FEAT_EVAL
+ --textwinlock;
+#endif
sub_nsubs++;
did_sub = TRUE;
diff -up vim82/src/testdir/test_substitute.vim.cve1785 vim82/src/testdir/test_substitute.vim
--- vim82/src/testdir/test_substitute.vim.cve1785 2022-06-10 10:26:16.910312568 +0200
+++ vim82/src/testdir/test_substitute.vim 2022-06-10 10:27:02.166084629 +0200
@@ -942,5 +942,18 @@ func Test_using_old_sub()
set nocompatible
endfunc
+" This was switching windows in between computing the length and using it.
+func Test_sub_change_window()
+ silent! lfile
+ sil! norm o0000000000000000000000000000000000000000000000000000
+ func Repl()
+ lopen
+ endfunc
+ silent! s/\%')/\=Repl()
+ bwipe!
+ bwipe!
+ delfunc Repl
+endfunc
+
" vim: shiftwidth=2 sts=2 expandtab