netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Sabrina Dubroca <sd@queasysnail.net>
To: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Cc: netdev@vger.kernel.org, yoshfuji@linux-ipv6.org,
	kuznet@ms2.inr.ac.ru, davem@davemloft.net,
	herbert@gondor.apana.org.au, steffen.klassert@secunet.com,
	eyal.birger@gmail.com
Subject: Re: [PATCH 1/2] xfrm6: call kfree_skb when skb is toobig
Date: Thu, 30 Aug 2018 15:23:11 +0200	[thread overview]
Message-ID: <20180830132310.GA29881@bistromath.localdomain> (raw)
In-Reply-To: <20180830125817.4567-1-cascardo@canonical.com>

2018-08-30, 09:58:16 -0300, Thadeu Lima de Souza Cascardo wrote:
> After commit d6990976af7c5d8f55903bfb4289b6fb030bf754 ("vti6: fix PMTU caching
> and reporting on xmit"), some too big skbs might be potentially passed down to
> __xfrm6_output, causing it to fail to transmit but not free the skb, causing a
> leak of skb, and consequentially a leak of dst references.
> 
> After running pmtu.sh, that shows as failure to unregister devices in a namespace:
> 
> [  311.397671] unregister_netdevice: waiting for veth_b to become free. Usage count = 1
> 
> The fix is to call kfree_skb in case of transmit failures.
> 
> Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>

Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>

I was about to post the same patch. Arguably, the commit introducing
this bug is the one that added those "return -EMSGSIZE" to
__xfrm6_output without freeing.

Either way, it's missing a Fixes: tag, which should be one of those,
or both:

Fixes: d6990976af7c ("vti6: fix PMTU caching and reporting on xmit")
Fixes: dd767856a36e ("xfrm6: Don't call icmpv6_send on local error")

-- 
Sabrina

  parent reply	other threads:[~2018-08-30 17:25 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-08-30 12:58 [PATCH 1/2] xfrm6: call kfree_skb when skb is toobig Thadeu Lima de Souza Cascardo
2018-08-30 12:58 ` [PATCH 2/2] vti6: do not check for ignore_df in order to update pmtu Thadeu Lima de Souza Cascardo
2018-08-31  6:42   ` Steffen Klassert
2018-08-30 13:23 ` Sabrina Dubroca [this message]
2018-08-31  6:47   ` [PATCH 1/2] xfrm6: call kfree_skb when skb is toobig Steffen Klassert
2018-08-31 11:38 ` [PATCH v2] " Thadeu Lima de Souza Cascardo
2018-09-03  8:21   ` Steffen Klassert

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=20180830132310.GA29881@bistromath.localdomain \
    --to=sd@queasysnail.net \
    --cc=cascardo@canonical.com \
    --cc=davem@davemloft.net \
    --cc=eyal.birger@gmail.com \
    --cc=herbert@gondor.apana.org.au \
    --cc=kuznet@ms2.inr.ac.ru \
    --cc=netdev@vger.kernel.org \
    --cc=steffen.klassert@secunet.com \
    --cc=yoshfuji@linux-ipv6.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).