From: Jim Baxter <jim_baxter@mentor.com>
To: Vlad Yasevich <vyasevich@gmail.com>, <linux-usb@vger.kernel.org>,
<linux-kernel@vger.kernel.org>,
"netdev@vger.kernel.org" <netdev@vger.kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>, <kamal@canonical.com>,
Ben Hutchings <bhutchings@solarflare.com>, <edumazet@google.com>,
<mszeredi@suse.cz>, <fw@strlen.de>
Subject: Re: skbuff truesize incorrect.
Date: Thu, 22 May 2014 20:39:27 +0100 [thread overview]
Message-ID: <537E526F.8060608@mentor.com> (raw)
In-Reply-To: <537E4F29.9080103@gmail.com>
On 22/05/14 20:25, Vlad Yasevich wrote:
> On 05/22/2014 03:07 PM, Jim Baxter wrote:
>>
>> skb2 = skb_clone(skb, GFP_ATOMIC);
>> if (skb2 == NULL)
>> goto err;
>>
>> if (!skb_pull(skb2, index)) {
>> ret = -EOVERFLOW;
>> goto err;
>> }
>
> This assumes that you original 16K packet is linear. Is that
> always the case?
The packets within the original packet are linear, however they could be
in an arbitrary order because they are just offsets from the start of
the 16k skb.
>
> This is the very same problem that I ran into with SCTP since it
> has similar code in it. You can play games with truesize manually,
> but you have to be very careful here.
>
> -vlad
I now think that the correct solution here is to create a new smaller
skb and copy the data from the sub packets into it.
Jim
next prev parent reply other threads:[~2014-05-22 19:39 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-05-22 19:07 skbuff truesize incorrect Jim Baxter
2014-05-22 19:21 ` David Miller
2014-05-22 20:21 ` Jim Baxter
2014-05-22 20:30 ` Eric Dumazet
2014-05-22 20:58 ` David Miller
2014-05-23 9:21 ` Jim Baxter
2014-05-23 9:27 ` David Laight
2014-05-23 16:46 ` David Miller
2014-05-22 19:25 ` Vlad Yasevich
2014-05-22 19:39 ` Jim Baxter [this message]
2014-05-22 19:59 ` Eric Dumazet
2014-05-22 20:21 ` Jim Baxter
2014-05-22 20:58 ` Eric Dumazet
2014-05-22 21:03 ` Eric Dumazet
2014-05-22 21:10 ` David Miller
2014-05-23 7:07 ` Bjørn Mork
2014-05-23 8:58 ` Jim Baxter
2014-05-23 9:33 ` Bjørn Mork
2014-05-23 14:00 ` Eric Dumazet
2014-05-23 15:44 ` Rick Jones
2014-05-23 16:00 ` Eric Dumazet
2014-05-23 8:52 ` David Laight
2014-05-23 9:48 ` Bjørn Mork
2014-05-23 10:45 ` David Laight
2014-05-23 11:13 ` Jim Baxter
2014-05-23 13:47 ` Eric Dumazet
2014-05-23 15:00 ` Jim Baxter
2014-05-23 15:30 ` David Laight
2014-05-23 15:41 ` Eric Dumazet
2014-05-23 20:18 ` David Miller
2014-05-27 15:23 ` David Laight
2014-05-27 15:52 ` David Miller
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