linux-kernel - Re: [PATCH] [DISCUSS] Make the variable NULL after freeing it.

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Date:	Thu, 28 Dec 2006 09:54:28 +0100 (MET)
From:	Jan Engelhardt <jengelh@...ux01.gwdg.de>
To:	Pavel Machek <pavel@....cz>
cc:	Amit Choudhary <amit2030@...oo.com>,
	Linux Kernel <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] [DISCUSS] Make the variable NULL after freeing it.


On Dec 27 2006 17:10, Pavel Machek wrote:

>> Was just wondering if the _var_ in kfree(_var_) could be set to
>> NULL after its freed. It may solve the problem of accessing some
>> freed memory as the kernel will crash since _var_ was set to NULL.
>> 
>> Does this make sense? If yes, then how about renaming kfree to
>> something else and providing a kfree macro that would do the
>> following:
>> 
>> #define kfree(x) do { \
>>                       new_kfree(x); \
>>                       x = NULL; \
>>                     } while(0)
>> 
>> There might be other better ways too.
>
>No, that would be very confusing. Otoh having
>KFREE() do kfree() and assignment might be acceptable.

What about setting x to some poison value from <linux/poison.h>?


	-`J'
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