netdev - Re: [PATCH] ipv4: use daddr to get inet

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Fri, 14 Feb 2014 11:35:19 +0100
From:	Hannes Frederic Sowa <hannes@...essinduktion.org>
To:	Duan Jiong <duanj.fnst@...fujitsu.com>
Cc:	David Miller <davem@...emloft.net>, netdev <netdev@...r.kernel.org>
Subject: Re: [PATCH] ipv4: use daddr to get inet_peer

On Fri, Feb 14, 2014 at 05:51:07PM +0800, Duan Jiong wrote:
> 于 2014年02月14日 17:41, Hannes Frederic Sowa 写道:
> > On Fri, Feb 14, 2014 at 05:25:35PM +0800, Duan Jiong wrote:
> >>
> >> since commit 1d861aa4("inet: Minimize use of cached route inetpeer"),
> >> ip_error() uses saddr to get inet_peer, so ip_error() and icmpv4_xrlim_allow()
> >> use the same inet_peer to limit icmp error message twice.
> >>
> >> In ip_error(), peer->rate_tokens is set to ip_rt_error_burst, but in
> >> inet_peer_xrlim_allow() peer->rate_tokens is set to XRLIM_BURST_FACTOR.
> >> XRLIM_BURST_FACTOR is defined to 6, so user seting ip_rt_error_burst makes
> >> no sense.
> >>
> >> In my opinion, the ip_rt_error_burst is used to limit icmp error messages
> >> for daddr instead of saddr.
> > 
> > Hmmm...
> > 
> > ip_error is a dst_input function, as such it gets called with the incoming
> > packet. saddr is the address we send the reply back (see
> > icmp_send->icmp_route_lookup).
> > 
> 
> But if we still use saddr to get inet_peer, seting ip_rt_error_burst will make
> no sense, because it will be overwrited by XRLIM_BURST_FACTOR.

Sorry, I cannot follow you.

On output we refetch the inetpeer with the destination address. I don't
see how the patch helps.

Greetings,

  Hannes

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html