From: Jakub Jelinek <jakub@redhat.com>
To: Ulrich Drepper <drepper@redhat.com>
Cc: Glibc hackers <libc-hacker@sources.redhat.com>
Subject: [PATCH] Avoid leaks in res_init
Date: Wed, 21 Jul 2004 17:39:00 -0000 [thread overview]
Message-ID: <20040721152324.GQ30497@sunsite.ms.mff.cuni.cz> (raw)
Hi!
#include <malloc.h>
#include <resolv.h>
#include <netdb.h>
int main (void)
{
int i;
mtrace ();
for (i = 0; i < 50; ++i)
{
res_init ();
gethostbyname ("www.google.com");
}
}
leaks memory and if IPv6 is enabled also filehandles.
I have googled around but could not find a word about whether
res_init can or can't be called multiple times, but certainly
we need such an interface e.g. for nscd to reread resolv.conf
during nscd -i hosts.
2004-07-21 Jakub Jelinek <jakub@redhat.com>
* resolv/res_libc.c (res_init): If RES_INIT is set and
_res.nscount > 0, call __res_nclose and free nsaddrs.
--- libc/resolv/res_libc.c.jj 2003-07-23 09:56:18.000000000 +0200
+++ libc/resolv/res_libc.c 2004-07-21 19:25:05.419402346 +0200
@@ -54,6 +54,14 @@ res_init(void) {
_res.retry = 4;
if (!(_res.options & RES_INIT))
_res.options = RES_DEFAULT;
+ else if (_res.nscount > 0) {
+ __res_nclose (&_res); /* Close any VC sockets. */
+
+ for (int ns = 0; ns < MAXNS; ns++) {
+ free (_res._u._ext.nsaddrs[ns]);
+ _res._u._ext.nsaddrs[ns] = NULL;
+ }
+ }
/*
* This one used to initialize implicitly to zero, so unless the app
Jakub
next reply other threads:[~2004-07-21 17:39 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-07-21 17:39 Jakub Jelinek [this message]
2004-07-21 18:07 ` [PATCH] tst-leaks2 Jakub Jelinek
2004-07-21 18:31 ` [PATCH] Avoid leaks in res_init Ulrich Drepper
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