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Date: Tue, 18 Jan 2011 18:59:22 +0100
From: Stefan Weil <weil@mail.berlios.de>
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Subject: Re: [Qemu-devel] [PATCH] linux-user: Fix possible realloc memory leak
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To: Markus Armbruster <armbru@redhat.com>
Cc: Riku Voipio <riku.voipio@iki.fi>, QEMU Developers <qemu-devel@nongnu.org>

Am 18.01.2011 18:51, schrieb Markus Armbruster:
> Stefan Weil<weil@mail.berlios.de>  writes:
>
>    
>> Am 18.01.2011 09:26, schrieb Markus Armbruster:
>>      
>>> Stefan Weil<weil@mail.berlios.de>  writes:
>>>
>>>        
>>>> Extract from "man realloc":
>>>> "If realloc() fails the original block is left untouched;
>>>> it is not freed or moved."
>>>>
>>>> Fix a possible memory leak (reported by cppcheck).
>>>>
>>>> Cc: Riku Voipio<riku.voipio@iki.fi>
>>>> Signed-off-by: Stefan Weil<weil@mail.berlios.de>
>>>>          
>>> Sidestep the problem via qemu_realloc() instead?
>>>        
>> The same change was applied to bsd-user/elfload.c.
>>
>> As symbol loading is not essential in most applications,
>> returning after out-of-memory should be better than
>> aborting (that's what qemu_realloc does).
>>      
> Unless the requested size is *really* large, I'd expect this to stave
> off the out-of-memory failure for a few microseconds at best.
>    

If realloc fails, some memory is released before returning,
so maybe you would be surprised that your program
finishes without any more problems :-)