netfilter-devel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Florian Westphal <fw@strlen.de>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Florian Westphal <fw@strlen.de>, netfilter-devel@vger.kernel.org
Subject: Re: [PATCH -next 3/4] netfilter: xtables: don't save/restore jumpstack offset
Date: Thu, 9 Jul 2015 11:14:15 +0200	[thread overview]
Message-ID: <20150709091415.GA17984@breakpoint.cc> (raw)
In-Reply-To: <1436428454.24939.13.camel@edumazet-glaptop2.roam.corp.google.com>

Eric Dumazet <eric.dumazet@gmail.com> wrote:
> > +	/* Switch to alternate jumpstack if we're being invoked via TEE.
> > +	 * The problem is that TEE issues XT_CONTINUE verdict on original
> > +	 * skb so we must not clobber the jumpstack.
> > +	 *
> > +	 * For recursion via REJECT or SYNPROXY the stack will be clobbered
> > +	 * but its no problem since absolute verdict is issued by these.
> > +	 */
> > +	jumpstack += private->stacksize * __this_cpu_read(nf_skb_duplicated);
> 
> This could eventually be garded by
> 
> #if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TEE)
> 
> Or even better, a jump label that would be enabled when TEE module is
> loaded.

I can add a static key, sure.

Thanks for the suggestion Eric.

  reply	other threads:[~2015-07-09  9:14 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-07-08 21:15 [PATCH -next 0/4] netfilter: xtables: improve jumpstack handling Florian Westphal
2015-07-08 21:15 ` [PATCH -next 1/4] xtables: compute exact size needed for jumpstack Florian Westphal
2015-07-08 21:15 ` [PATCH -next 2/4] netfilter: move tee_active to core Florian Westphal
2015-07-08 21:15 ` [PATCH -next 3/4] netfilter: xtables: don't save/restore jumpstack offset Florian Westphal
2015-07-08 21:47   ` Jan Engelhardt
2015-07-09  0:29     ` Florian Westphal
2015-07-09  8:16       ` Jan Engelhardt
2015-07-09  7:54   ` Eric Dumazet
2015-07-09  9:14     ` Florian Westphal [this message]
2015-07-08 21:15 ` [PATCH RFC -next 4/4] netfilter: xtables: add upper limit on call chain depth Florian Westphal

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=20150709091415.GA17984@breakpoint.cc \
    --to=fw@strlen.de \
    --cc=eric.dumazet@gmail.com \
    --cc=netfilter-devel@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 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).