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From: chetan loke <loke.chetan@gmail.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: netdev@vger.kernel.org, davem@davemloft.net, kaber@trash.net,
	johann.baudy@gnu-log.net, Chetan Loke <lokec@ccs.neu.edu>
Subject: Re: [af-packet 1/2] Enhance af-packet to provide (near zero)lossless packet capture functionality.
Date: Wed, 8 Jun 2011 18:10:02 -0400	[thread overview]
Message-ID: <BANLkTi=_EFRaiPuT=OjwRaJ4XPw0sUhcnA@mail.gmail.com> (raw)
In-Reply-To: <1307507754.3102.18.camel@edumazet-laptop>

On Wed, Jun 8, 2011 at 12:35 AM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
> Le mardi 07 juin 2011 à 23:13 -0400, Chetan Loke a écrit :
>>
>> +struct tpacket3_hdr {
>> +     __u32           tp_status;
>> +     __u32           tp_len;
>> +     __u32           tp_snaplen;
>> +     __u16           tp_mac;
>> +     __u16           tp_net;
>
>> +     __u32           tp_sec;
>> +     __u32           tp_nsec;
>> +     __u16           tp_vlan_tci;
>
> missing "__u16 tp_padding;" here
>
> check :
>
> http://git2.kernel.org/?p=linux/kernel/git/davem/net-2.6.git;a=commit;h=13fcb7bd322164c67926ffe272846d4860196dc6


Eric, thanks for pointing that. I will add the padding. But just out
of curiosity, how is the information being leaked in tpacket_rcv()?

If someone is capturing packets then they have access to all the data
anyways. Also, tpacket_rcv doesn't memset the frame-element to 'zero'
before calling
skb_copy_bits(). And we would never want to memset anyways.

thnx
Chetan Loke

  reply	other threads:[~2011-06-08 22:10 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-06-08  3:13 [af-packet 0/2] Enhance af-packet to provide (near zero)lossless packet capture functionality Chetan Loke
2011-06-08  3:13 ` [af-packet 1/2] " Chetan Loke
2011-06-08  4:35   ` Eric Dumazet
2011-06-08 22:10     ` chetan loke [this message]
2011-06-08 22:22       ` Eric Dumazet
2011-06-08 16:03   ` Stephen Hemminger
2011-06-08  3:13 ` [af-packet 2/2] " Chetan Loke
2011-06-08  4:18   ` Joe Perches
2011-06-08 22:01     ` chetan loke

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