From: Vincent Pit <vince@profvince.com>
Date: Sat, 27 Sep 2008 23:05:43 +0000 (+0200)
Subject: Hide previously deleted magic tokens in vmg_svt_free (Yuval Kogman)
X-Git-Tag: v0.21_02~1
X-Git-Url: http://git.vpit.fr/?a=commitdiff_plain;h=4323766d111bf2a00bcd68fc8ce18fa34ef00e46;p=perl%2Fmodules%2FVariable-Magic.git

Hide previously deleted magic tokens in vmg_svt_free (Yuval Kogman)
---

diff --git a/Magic.xs b/Magic.xs
index d9bc4b4..2883f00 100644
--- a/Magic.xs
+++ b/Magic.xs
@@ -548,6 +548,12 @@ STATIC int vmg_svt_clear(pTHX_ SV *sv, MAGIC *mg) {
 STATIC int vmg_svt_free(pTHX_ SV *sv, MAGIC *mg) {
  /* So that it can survive tmp cleanup in vmg_cb_call */
  SvREFCNT_inc(sv);
+#if !VMG_HAS_PERL_AND(32686, 5, 11, 0)
+ /* The previous magic tokens were freed but the magic chain wasn't updated, so
+  * if you access the sv from the callback the old deleted magics will trigger
+  * and cause memory misreads. Change 32686 solved it that way : */
+ SvMAGIC_set(sv, mg);
+#endif
  /* Perl_mg_free will get rid of the magic and decrement mg->mg_obj and
   * mg->mg_ptr reference count */
  return vmg_cb_call1(SV2MGWIZ(mg->mg_ptr)->cb_free, sv, mg->mg_obj);