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Date:   Fri, 08 Feb 2019 23:04:35 -0800 (PST)
Message-Id: <20190208.230435.620453531327055896.davem@davemloft.net>
To:     gustavo@embeddedor.com
Cc:     jeffrey.t.kirsher@intel.com, intel-wired-lan@lists.osuosl.org,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH net-next] igc: Use struct_size() helper
From:   David Miller <davem@davemloft.net>
In-Reply-To: <20190208041945.GA4687@embeddedor>
References: <20190208041945.GA4687@embeddedor>
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From: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
Date: Thu, 7 Feb 2019 22:19:45 -0600

> One of the more common cases of allocation size calculations is finding
> the size of a structure that has a zero-sized array at the end, along
> with memory for some number of elements for that array. For example:
> 
> struct foo {
>     int stuff;
>     struct boo entry[];
> };
> 
> size = sizeof(struct foo) + count * sizeof(struct boo);
> instance = kzalloc(size, GFP_KERNEL)
> 
> Instead of leaving these open-coded and prone to type mistakes, we can
> now use the new struct_size() helper:
> 
> instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL)
> 
> Notice that, in this case, variable size is not necessary, hence
> it is removed.
> 
> This code was detected with the help of Coccinelle.
> 
> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>

Applied.