linux-kernel - kfree a pointer "from the middle" causing protection faults

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Message-ID: <CAHhAz+g7HJX1HAYqyZT9VLV9GerJT7iuiJ=2ahHFLFX-O2ryQA@mail.gmail.com>
Date:	Wed, 2 Sep 2015 20:32:15 +0530
From:	Muni Sekhar <munisekharrms@...il.com>
To:	linux-kernel@...r.kernel.org
Subject: kfree a pointer "from the middle" causing protection faults

 [ Please keep me in CC as I'm not subscribed to the list]

Hello,


I am getting protection faults in different kernel modules if I try to
free a pointer "from the middle" for example, look at the following
code:


u8 *buf;


buf = kzalloc( 100 , GFP_KERNEL );

…

buf = buf + 50;

…

Kfree(buf);




I would like to know, why the above code is causing protection faults
in other kernel modules?


Regards,
Sekhar
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