netdev - Re: [PATCH net-next 6/6] net: Implmement RFC 6936 (zero RX csums for UDP/IPv6)

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: Windows password security audit tool. GUI, reports in PDF.

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

Message-Id: <20140407.131633.1635128478858805272.davem@davemloft.net>
Date:	Mon, 07 Apr 2014 13:16:33 -0400 (EDT)
From:	David Miller <davem@...emloft.net>
To:	therbert@...gle.com
Cc:	netdev@...r.kernel.org
Subject: Re: [PATCH net-next 6/6] net: Implmement RFC 6936 (zero RX csums
 for UDP/IPv6)

From: Tom Herbert <therbert@...gle.com>
Date: Fri, 4 Apr 2014 17:28:24 -0700 (PDT)

> RFC 6936 relaxes the requirement of RFC 2460 that UDP/IPv6 packets which
> are received with a zero UDP checksum value must be dropped. RFC 6936
> allow zero checksums to support tunnels over UDP.
> 
> This patch adds a new socket option UDP_CHECK6_ZERO_OKAY whcih can be
> set on a UDP socket to indicate that a zero checksum is acceptable
> (e.g. the socket is for a tunnel). The ip6 checksum and UDP receive
> functions were updated accordingly to deal with this.
> 
> Signed-off-by: Tom Herbert <therbert@...gle.com>

I see you reply to this later and say we can use sk_no_check.

Are you really sure?  This might create a surprise for someone
inadvertantly setting that now and expecting it to have a very
specific effect only for ipv4 UDP sockets.

The safest thing to do is to create the new option, then there
is no discrepancy.
--
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