|
 |
ab295a |
From b52cdd7a8525325deba04554d8a00a578c397d56 Mon Sep 17 00:00:00 2001
|
|
|
ab295a |
From: David Mitchell <davem@iabyn.com>
|
|
|
ab295a |
Date: Thu, 11 Jul 2019 15:17:48 +0100
|
|
|
ab295a |
Subject: [PATCH] threads::shared: fix leak
|
|
|
ab295a |
MIME-Version: 1.0
|
|
|
ab295a |
Content-Type: text/plain; charset=UTF-8
|
|
|
ab295a |
Content-Transfer-Encoding: 8bit
|
|
|
ab295a |
|
|
|
ab295a |
When assigning a shared reference value to a variable containing a
|
|
|
ab295a |
shared string, the PV buffer in the shared space was leaked. For
|
|
|
ab295a |
example:
|
|
|
ab295a |
|
|
|
ab295a |
my $s :shared = "foo";
|
|
|
ab295a |
my $t :shared = shared_clone(\"bar");
|
|
|
ab295a |
$s = $t; # "foo" in shared space leaked
|
|
|
ab295a |
|
|
|
ab295a |
This was showing up as failed smokes under ASan.
|
|
|
ab295a |
|
|
|
ab295a |
Petr Písař: Ported to 1.60 from perl commit
|
|
|
ab295a |
59c73bd3d62c5096a6f9b2e3cbe05e1ab4c158cf.
|
|
|
ab295a |
|
|
|
ab295a |
Signed-off-by: Petr Písař <ppisar@redhat.com>
|
|
|
ab295a |
---
|
|
|
ab295a |
shared.xs | 15 +++++++++++----
|
|
|
ab295a |
1 file changed, 11 insertions(+), 4 deletions(-)
|
|
|
ab295a |
|
|
|
ab295a |
diff --git a/shared.xs b/shared.xs
|
|
|
ab295a |
index 6cdf094..858c6d6 100644
|
|
|
ab295a |
--- a/shared.xs
|
|
|
ab295a |
+++ b/shared.xs
|
|
|
ab295a |
@@ -818,12 +818,19 @@ sharedsv_scalar_store(pTHX_ SV *sv, SV *ssv)
|
|
|
ab295a |
SV *obj = SvRV(sv);
|
|
|
ab295a |
SV *sobj = Perl_sharedsv_find(aTHX_ obj);
|
|
|
ab295a |
if (sobj) {
|
|
|
ab295a |
+ SV* tmpref;
|
|
|
ab295a |
SHARED_CONTEXT;
|
|
|
ab295a |
- (void)SvUPGRADE(ssv, SVt_RV);
|
|
|
ab295a |
- sv_setsv_nomg(ssv, &PL_sv_undef);
|
|
|
ab295a |
+ /* Creating a tmp ref to sobj then assigning it to ssv ensures
|
|
|
ab295a |
+ * that any previous contents of ssv are correctly freed
|
|
|
ab295a |
+ * by sv_setsv(). Not sure if there is a better, API-legal way
|
|
|
ab295a |
+ * to achieve this */
|
|
|
ab295a |
+ tmpref = newSV_type(SVt_RV);
|
|
|
ab295a |
+ SvRV_set(tmpref, sobj);
|
|
|
ab295a |
+ SvROK_on(tmpref);
|
|
|
ab295a |
+ SvREFCNT_inc_simple_NN(sobj);
|
|
|
ab295a |
+ sv_setsv_nomg(ssv, tmpref);
|
|
|
ab295a |
+ SvREFCNT_dec_NN(tmpref);
|
|
|
ab295a |
|
|
|
ab295a |
- SvRV_set(ssv, SvREFCNT_inc(sobj));
|
|
|
ab295a |
- SvROK_on(ssv);
|
|
|
ab295a |
if (SvOBJECT(sobj)) {
|
|
|
ab295a |
/* Remove any old blessing */
|
|
|
ab295a |
SvREFCNT_dec(SvSTASH(sobj));
|
|
|
ab295a |
--
|
|
|
ab295a |
2.20.1
|
|
|
ab295a |
|