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Subject: Re: [PATCH] netlink: Fix kfree NULL pointer
From: Eric Dumazet <eric.dumazet@gmail.com>
To: jovi zhang <bookjovi@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>,
        Johannes Berg <johannes.berg@intel.com>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        Alexey Dobriyan <adobriyan@openvz.org>, linux-kernel@vger.kernel.org,
        netdev@vger.kernel.org
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Date: Wed, 08 Sep 2010 07:55:24 +0200
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Le mercredi 08 septembre 2010 à 13:33 +0800, jovi zhang a écrit :

> YES, maybe kfree(NULL) is legal, but I cannot see there have any need
> to invoke kfree(NULL) in this function.
>  Also I check kfree usage in other code, I havn't find any kfree(NULL) usage.

We have hundred call sites doing kfree(NULL), if it makes code shorter.

Its usually code path handling exceptions (errors if you prefer), and we
prefer to use ugly gotos, and even kfree(NULL), to make it as short as
possible.