netdev - Re: [PATCH v2 net-next 07/14] ipv6: add GRO_IPV6_MAX

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]

Date:   Thu, 3 Mar 2022 21:37:17 -0700
From:   David Ahern <dsahern@...nel.org>
To:     Eric Dumazet <eric.dumazet@...il.com>,
        "David S . Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>
Cc:     netdev <netdev@...r.kernel.org>,
        Eric Dumazet <edumazet@...gle.com>,
        Coco Li <lixiaoyan@...gle.com>,
        Alexander Duyck <alexanderduyck@...com>
Subject: Re: [PATCH v2 net-next 07/14] ipv6: add GRO_IPV6_MAX_SIZE

On 3/3/22 11:16 AM, Eric Dumazet wrote:
> From: Coco Li <lixiaoyan@...gle.com>
> 
> Enable GRO to have IPv6 specific limit for max packet size.
> 
> This patch introduces new dev->gro_ipv6_max_size
> that is modifiable through ip link.
> 
> ip link set dev eth0 gro_ipv6_max_size 185000
> 
> Note that this value is only considered if bigger than
> gro_max_size, and for non encapsulated TCP/ipv6 packets.
> 

What is the point of a max size for the Rx path that is per ingress
device? If the stack understands the larger packets then the ingress
device limits should not matter. (yes, I realize the existing code has
it this way, so I guess this is a historical question)