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Date: Thu, 21 Oct 2010 15:08:47 +0200
From: Nicolas Kaiser <nikai@nikai.net>
To: Shan Wei <shanwei@cn.fujitsu.com>
Cc: Vlad Yasevich <vladislav.yasevich@hp.com>,
        Sridhar Samudrala <sri@us.ibm.com>, linux-sctp@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] sctp: remove redundant chunk length check
Message-ID: <20101021150847.3a5f3cb7@absol.kitzblitz>
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* Shan Wei <shanwei@cn.fujitsu.com>:
> Nicolas Kaiser wrote, at 10/21/2010 06:14 PM:
> > Checking the chunk length at this point appears redundant, as
> > the rest of the packet gets discarded anyway.
 
> Yes, indeed.
> 
> How did you find this? By reviewing the source code?

Actually I'm tinkering with Coccinelle patches.

Here's a simple semantic patch, that will give a lot of false
positives, and a lot of "if (a) return b; return b;":

// <smpl>
@@
expression a;
statement S;
@@

- if (a)
- {
- S
- }
 S
// </smpl>

Best regards,
Nicolas Kaiser