From: Rongqing Li <rongqing.li@windriver•com>
To: Eric Dumazet <eric.dumazet@gmail•com>
Cc: <netdev@vger•kernel.org>
Subject: Re: [PATCH 1/1] snmp6 relevant data structures are freed twice.
Date: Mon, 19 Sep 2011 16:32:48 +0800 [thread overview]
Message-ID: <4E76FE30.4000204@windriver.com> (raw)
In-Reply-To: <1316420989.2539.5.camel@edumazet-HP-Compaq-6005-Pro-SFF-PC>
On 09/19/2011 04:29 PM, Eric Dumazet wrote:
> Le lundi 19 septembre 2011 à 15:03 +0800, rongqing.li@windriver•com a
> écrit :
>> From: Roy.Li<rongqing.li@windriver•com>
>>
>> When calling snmp6_alloc_dev fails, the snmp6 relevant memory
>> are freed by snmp6_alloc_dev. Calling in6_dev_finish_destroy
>> will free these memory twice.
>>
>> Double free will lead that undefined behavior occurs.
>>
>> Signed-off-by: Roy.Li<rongqing.li@windriver•com>
>> ---
>> net/ipv6/addrconf.c | 4 ++--
>> 1 files changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
>> index 8f1e5be..ba01f72 100644
>> --- a/net/ipv6/addrconf.c
>> +++ b/net/ipv6/addrconf.c
>> @@ -374,8 +374,8 @@ static struct inet6_dev * ipv6_add_dev(struct net_device *dev)
>> "%s(): cannot allocate memory for statistics; dev=%s.\n",
>> __func__, dev->name));
>> neigh_parms_release(&nd_tbl, ndev->nd_parms);
>> - ndev->dead = 1;
>> - in6_dev_finish_destroy(ndev);
>> + dev_put(dev);
>> + kfree(ndev);
>> return NULL;
>> }
>>
>
> This seems a very old bug, and your fix applicable to old kernels as
> well, thanks.
>
> Could your patch title could be refined to the following ?
>
> 0) No need for the 1/1 suffix
> 1) include ipv6: prefix
> 2) change the message a bit, since normal operations are OK, only
> failure and error recovery is buggy.
>
> [PATCH] ipv6: fix a possible double free
>
> Acked-by: Eric Dumazet<eric.dumazet@gmail•com>
>
>
>
Ok, I will resend it.
--
Best Reagrds,
Roy | RongQing Li
prev parent reply other threads:[~2011-09-19 8:32 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-09-19 7:03 [PATCH 1/1] snmp6 relevant data structures are freed twice rongqing.li
2011-09-19 8:29 ` Eric Dumazet
2011-09-19 8:32 ` Rongqing Li [this message]
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=4E76FE30.4000204@windriver.com \
--to=rongqing.li@windriver$(echo .)com \
--cc=eric.dumazet@gmail$(echo .)com \
--cc=netdev@vger$(echo .)kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox