From bc7fb8964ca3a422f472189b0eff751c1cc377b0 Mon Sep 17 00:00:00 2001
From: zherczeg <zherczeg@6239d852-aaf2-0410-a92c-79f79f948069>
Date: Mon, 9 Sep 2019 07:12:00 +0000
Subject: [PATCH] Add underflow check in JIT.
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git-svn-id: svn://vcs.exim.org/pcre2/code/trunk@1167 6239d852-aaf2-0410-a92c-79f79f948069
Petr Písař: Ported to 10.33.
---
 src/pcre2_jit_compile.c | 8 ++++++--

diff --git a/src/pcre2_jit_compile.c b/src/pcre2_jit_compile.c
index 8cbd8f9..79a27fd 100644
--- a/src/pcre2_jit_compile.c
+++ b/src/pcre2_jit_compile.c
@@ -5793,12 +5793,16 @@ if (common->match_end_ptr != 0)
   {
   OP1(SLJIT_MOV, TMP1, 0, SLJIT_MEM1(SLJIT_SP), common->match_end_ptr);
   OP1(SLJIT_MOV, TMP3, 0, STR_END, 0);
-  OP2(SLJIT_SUB, STR_END, 0, STR_END, 0, SLJIT_IMM, IN_UCHARS(max));
+  OP2(SLJIT_SUB | SLJIT_SET_LESS, STR_END, 0, STR_END, 0, SLJIT_IMM, IN_UCHARS(max));
+  add_jump(compiler, &common->failed_match, JUMP(SLJIT_LESS));
   OP2(SLJIT_SUB | SLJIT_SET_GREATER, SLJIT_UNUSED, 0, STR_END, 0, TMP1, 0);
   CMOV(SLJIT_GREATER, STR_END, TMP1, 0);
   }
 else
-  OP2(SLJIT_SUB, STR_END, 0, STR_END, 0, SLJIT_IMM, IN_UCHARS(max));
+  {
+  OP2(SLJIT_SUB | SLJIT_SET_LESS, STR_END, 0, STR_END, 0, SLJIT_IMM, IN_UCHARS(max));
+  add_jump(compiler, &common->failed_match, JUMP(SLJIT_LESS));
+  }
 
 SLJIT_ASSERT(range_right >= 0);
 
-- 
2.21.0