All of lore.kernel.org
 help / color / mirror / Atom feed
From: David Marchand <david.marchand@pace.com>
To: netdev@vger.kernel.org
Subject: [RFC] Move in6_dev_hold under CONFIG_IPV6_PRIVACY
Date: Thu, 30 Aug 2012 11:42:33 +0200	[thread overview]
Message-ID: <503F3589.5070804@pace.com> (raw)

Hello,

I am currently looking at a problem with in6 interface refcnt on a 
really old kernel and I have just noticed something I find suspicious in 
all kernels until now.

The comment at net/ipv6/addrconf.c:396 suggests that the call to 
in6_dev_hold is only for ipv6_regen_rndid.
As a consequence, if CONFIG_IPV6_PRIVACY is not set, then this 
in6_dev_hold will leak a refcnt.

Can someone look at this ?
I did not test this patch, yet it looks reasonable to me.

Thank you.


$ git diff
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 6bc85f7..263fcf3 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -393,11 +393,6 @@ static struct inet6_dev *ipv6_add_dev(struct 
net_device *dev)
                 return NULL;
         }

-       /* One reference from device.  We must do this before
-        * we invoke __ipv6_regen_rndid().
-        */
-       in6_dev_hold(ndev);
-
         if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
                 ndev->cnf.accept_dad = -1;

@@ -410,6 +405,12 @@ static struct inet6_dev *ipv6_add_dev(struct 
net_device *dev)

  #ifdef CONFIG_IPV6_PRIVACY
         INIT_LIST_HEAD(&ndev->tempaddr_list);
+
+       /* One reference from device.  We must do this before
+        * we invoke ipv6_regen_rndid().
+        */
+       in6_dev_hold(ndev);
+
         setup_timer(&ndev->regen_timer, ipv6_regen_rndid, (unsigned 
long)ndev);
         if ((dev->flags&IFF_LOOPBACK) ||
             dev->type == ARPHRD_TUNNEL ||



-- 
David Marchand


This message has been scanned for viruses by BlackSpider MailControl. - www.blackspider.com

             reply	other threads:[~2012-08-30 10:32 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-08-30  9:42 David Marchand [this message]
2012-08-30 15:25 ` [RFC] Move in6_dev_hold under CONFIG_IPV6_PRIVACY Eric Dumazet
2012-08-30 16:52   ` David Marchand
2012-08-30 17:28     ` Eric Dumazet

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=503F3589.5070804@pace.com \
    --to=david.marchand@pace.com \
    --cc=netdev@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.