vim/backport-CVE-2021-3974.patch
ExtinctFire a1622b8443 fix CVE-2021-3973 CVE-2021-3974
Signed-off-by: ExtinctFire <shenyining_00@126.com>
(cherry picked from commit 20e53e3a69bad745d01299378ff5fdac9b08aa22)
2021-12-01 11:31:46 +08:00

67 lines
2.2 KiB
Diff

From 64066b9acd9f8cffdf4840f797748f938a13f2d6 Mon Sep 17 00:00:00 2001
From: Bram Moolenaar <Bram@vim.org>
Date: Wed, 17 Nov 2021 18:22:56 +0000
Subject: [PATCH] patch 8.2.3612: using freed memory with regexp using a mark
Problem: Using freed memory with regexp using a mark.
Solution: Get the line again after getting the mark position.
Reference:https://github.com/vim/vim/commit/64066b9acd9f8cffdf4840f797748f938a13f2d6
---
src/regexp.c | 2 +-
src/regexp_nfa.c | 8 ++++++++
src/testdir/test_regexp_latin.vim | 8 ++++++++
3 files changed, 17 insertions(+), 1 deletion(-)
diff --git a/src/regexp.c b/src/regexp.c
index 112f753..2e94e5a 100644
--- a/src/regexp.c
+++ b/src/regexp.c
@@ -1092,7 +1092,7 @@ typedef struct {
// The current match-position is stord in these variables:
linenr_T lnum; // line number, relative to first line
char_u *line; // start of current line
- char_u *input; // current input, points into "regline"
+ char_u *input; // current input, points into "line"
int need_clear_subexpr; // subexpressions still need to be cleared
#ifdef FEAT_SYN_HL
diff --git a/src/regexp_nfa.c b/src/regexp_nfa.c
index bc4a4b6..433523e 100644
--- a/src/regexp_nfa.c
+++ b/src/regexp_nfa.c
@@ -6623,8 +6623,16 @@ nfa_regmatch(
case NFA_MARK_GT:
case NFA_MARK_LT:
{
+ size_t col = rex.input - rex.line;
pos_T *pos = getmark_buf(rex.reg_buf, t->state->val, FALSE);
+ // Line may have been freed, get it again.
+ if (REG_MULTI)
+ {
+ rex.line = reg_getline(rex.lnum);
+ rex.input = rex.line + col;
+ }
+
// Compare the mark position to the match position.
result = (pos != NULL // mark doesn't exist
&& pos->lnum > 0 // mark isn't set in reg_buf
diff --git a/src/testdir/test_regexp_latin.vim b/src/testdir/test_regexp_latin.vim
index 7a4d98f..3168edc 100644
--- a/src/testdir/test_regexp_latin.vim
+++ b/src/testdir/test_regexp_latin.vim
@@ -141,3 +141,11 @@ func Test_pattern_compile_speed()
call assert_inrange(0.01, 10.0, reltimefloat(reltime(start)))
set spc=
endfunc
+
+func Test_using_mark_position()
+ " this was using freed memory
+ new
+ norm O0
+ call assert_fails("s/\\%')", 'E486:')
+ bwipe!
+endfunc
--
2.23.0