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Subject: Re: malloc() returns pointer to already allocated memory
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Date: Mon, 17 Jun 2019 18:31:50 +0200
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On 2019-06-17 07:48, Rod Pemberton wrote:
> One thing he could do is reduce the likelihood, i.e., probability, that
> he'll get a false positive, i.e., random value.  He could check for
> multiple magic values in a row.  The more values he checks for, the
> lower the probability will be that it's random.  I'd probably
> check for an entire block.
Then the test also depends on how well aligned the pointers returned by 
malloc are. eg. you write a 16-byte value to 0x1000, if malloc next 
returns a pointer to 0x1008 it still overlaps, but this would be more 
difficult to detect.