netdev - Re: [PATCH] User mode linux bump maximum MTU tuntap interface [RESAND]

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

Message-ID: <1fb36224-81c0-0c4c-72c4-5a60dfe207ef@cambridgegreys.com>
Date:   Fri, 12 Jul 2019 10:22:41 +0100
From:   Anton Ivanov <anton.ivanov@...bridgegreys.com>
To:     Richard Weinberger <richard.weinberger@...il.com>,
        Алексей <ne-vlezay80@...dex.ru>
Cc:     netdev@...r.kernel.org, linux-um@...ts.infradead.org
Subject: Re: [PATCH] User mode linux bump maximum MTU tuntap interface
 [RESAND]

On 02/07/2019 15:40, Richard Weinberger wrote:
> CC'ing um folks.
> 
> On Tue, Jul 2, 2019 at 3:01 PM Алексей <ne-vlezay80@...dex.ru> wrote:
>>
>> Hello, the parameter  ETH_MAX_PACKET limited to 1500 bytes is the not
>> support jumbo frames.
>>
>> This patch change ETH_MAX_PACKET the 65535 bytes to jumbo frame support
>> with user mode linux tuntap driver.
>>
>>
>> PATCH:
>>
>> -------------------
>>
>>
>> diff -ruNP ../linux_orig/linux-5.1/arch/um/include/shared/net_user.h
>> ./arch/um/include/shared/net_user.h
>> --- a/arch/um/include/shared/net_user.h    2019-05-06 00:42:58.000000000
>> +0000
>> +++ b/arch/um/include/shared/net_user.h    2019-07-02 07:14:13.593333356
>> +0000
>> @@ -9,7 +9,7 @@
>>   #define ETH_ADDR_LEN (6)
>>   #define ETH_HEADER_ETHERTAP (16)
>>   #define ETH_HEADER_OTHER (26) /* 14 for ethernet + VLAN + MPLS for
>> crazy people */
>> -#define ETH_MAX_PACKET (1500)
>> +#define ETH_MAX_PACKET (65535)
>>
>>   #define UML_NET_VERSION (4)
>>
>> -------------------
>>
>>
> 
> 

This does not quite work because in some of the drivers you get extra 
added on top of this constant.

I am going to see what can be done to fix the old net* drivers, imho we 
should start phasing them out in favor of the vector ones.

-- 
Anton R. Ivanov
Cambridgegreys Limited. Registered in England. Company Number 10273661
https://www.cambridgegreys.com/