From 979ae704ddc9e6f19d8dbf7a83bea155065ef3cc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Petr=20P=C3=ADsa=C5=99?= <ppisar@redhat.com>
Date: Mon, 6 Feb 2017 15:26:09 +0100
Subject: [PATCH] prevent leak of class name from retrieve_hook() on an
exception
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Ported from perl:
commit da1ec2b1b9abdfd956d9c539abf39d908d046304
Author: Tony Cook <tony@develop-help.com>
Date: Mon Feb 6 11:38:10 2017 +1100
prevent leak of class name from retrieve_hook() on an exception
If supplied with a large class name, retrieve_hook() allocates
buffer for the class name and Safefree()s it on exit path.
Unfortunately this memory leaks if load_module() (or a couple of other
code paths) throw an exception.
So use SAVEFREEPV() to release the memory instead.
==20183== 193 bytes in 1 blocks are definitely lost in loss record 4 of 6
==20183== at 0x4C28C20: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==20183== by 0x55F85D: Perl_safesysmalloc (util.c:153)
==20183== by 0x6ACA046: retrieve_hook (Storable.xs:4265)
==20183== by 0x6AD6D19: retrieve (Storable.xs:6217)
==20183== by 0x6AD8144: do_retrieve (Storable.xs:6401)
==20183== by 0x6AD85B7: pretrieve (Storable.xs:6506)
==20183== by 0x6AD8E14: XS_Storable_pretrieve (Storable.xs:6718)
==20183== by 0x5C176D: Perl_pp_entersub (pp_hot.c:4227)
==20183== by 0x55E1C6: Perl_runops_debug (dump.c:2450)
==20183== by 0x461B79: S_run_body (perl.c:2528)
==20183== by 0x46115C: perl_run (perl.c:2451)
==20183== by 0x41F1CD: main (perlmain.c:123)
Signed-off-by: Petr Písař <ppisar@redhat.com>
---
Storable.xs | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/Storable.xs b/Storable.xs
index 3cce3ed..75ce3df 100644
--- a/Storable.xs
+++ b/Storable.xs
@@ -4249,6 +4249,11 @@ static SV *retrieve_hook(pTHX_ stcxt_t *cxt, const char *cname)
TRACEME(("class name: %s", classname));
+ if (!(flags & SHF_IDX_CLASSNAME) && classname != buf) {
+ /* some execution paths can throw an exception */
+ SAVEFREEPV(classname);
+ }
+
/*
* Decode user-frozen string length and read it in an SV.
*
@@ -4367,8 +4372,6 @@ static SV *retrieve_hook(pTHX_ stcxt_t *cxt, const char *cname)
SEEN0(sv, 0);
SvRV_set(attached, NULL);
SvREFCNT_dec(attached);
- if (!(flags & SHF_IDX_CLASSNAME) && classname != buf)
- Safefree(classname);
return sv;
}
CROAK(("STORABLE_attach did not return a %s object", classname));
@@ -4449,8 +4452,6 @@ static SV *retrieve_hook(pTHX_ stcxt_t *cxt, const char *cname)
SvREFCNT_dec(frozen);
av_undef(av);
sv_free((SV *) av);
- if (!(flags & SHF_IDX_CLASSNAME) && classname != buf)
- Safefree(classname);
/*
* If we had an <extra> type, then the object was not as simple, and
--
2.7.4