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Subject: Re: [PATCH] drivers/net/wimax/i2400m/fw.c fix possible double free
From: Darren Jenkins <darrenrjenkins@gmail.com>
To: Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
Cc: David Miller <davem@davemloft.net>, linux-wimax <linux-wimax@intel.com>,
       "kernel-janitors@vger.kernel.org" <kernel-janitors@vger.kernel.org>,
       "Kao, Cindy H" <cindy.h.kao@intel.com>,
       "Brandewie, Dirk J" <dirk.j.brandewie@intel.com>,
       "wimax@linuxwimax.org" <wimax@linuxwimax.org>,
       "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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Date: Thu, 18 Mar 2010 19:46:48 +1100
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On Thu, Mar 18, 2010 at 9:10 AM, Inaky Perez-Gonzalez
<inaky.perez-gonzalez@intel.com> wrote:

> If krealloc() fails to aallocate a new pointer, the old block is
> unmodified, so by doing this you are leaking a buffer allocation.

It seems you are right.
So now understanding correctly how krealloc() works I can see that the
double kfree() can only actually happen if the el_size parameter to
i2400m_zrealloc_2x() is zero, and it isn't at the two call sites.

So this was a false positive and I am sorry for the noise.

Darren J.