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Message-ID: <661de9470603052326i5f4a6a7q79bc370d180737b1@mail.gmail.com>
Date: Mon, 6 Mar 2006 12:56:03 +0530
From: "Balbir Singh" <bsingharora@gmail.com>
To: "David S. Miller" <davem@davemloft.net>
Subject: Re: 9pfs double kfree
Cc: davej@redhat.com, linux-kernel@vger.kernel.org, ericvh@gmail.com,
       rminnich@lanl.gov
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On 3/6/06, David S. Miller <davem@davemloft.net> wrote:
> From: Dave Jones <davej@redhat.com>
> Date: Mon, 6 Mar 2006 02:04:58 -0500
>
> > (I wish we had a kfree variant that NULL'd the target when it was free'd)
>
> Excellent idea.
> -

Slab debugging should catch double frees, but it will not attract your
attention till you see your dmesg log. kfree() will ignore NULL
pointer, from the comments in kfree

/**
  * kfree - free previously allocated memory
  * @objp: pointer returned by kmalloc.
 *
  * If @objp is NULL, no operation is performed.
<snip>

May we could have such a variant under CONFIG_DEBUG_SLAB if we needed
and also change the variant kfree to BUG_ON() a NULL pointer.

Balbir
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