On Thu, Oct 6, 2011 at 11:28 AM, Mulyadi Santosa <mulyadi.santosa@xxxxxxxxx> wrote:
Hi...
Probably this could also due to mmap NULL dereferencing protection (at
On Thu, Oct 6, 2011 at 02:34, Vaibhav Jain <vjoss197@xxxxxxxxx> wrote:
> Hi,
>
> I am trying to run a program that scans memory from a given physical address
> using /dev/mem.
> It uses mmap to map physical address from /dev/mem. So to start with I used
> /proc/iomem to look up the
> physical memory mapping and found the address 00010000 to be the starting
> address for System ram. But whenever I
> provide this address to the program it throws an error of "Operation not
> permitted".
least that's how I name it :) )
By default, the lowest 65536 byte (10000 in hex) is protected from
mapping etc. It practically render such null dererefencing useless.
--
regards,
Mulyadi Santosa
Freelance Linux trainer and consultant
blog: the-hydra.blogspot.com
training: mulyaditraining.blogspot.com
Hi,
I tried the same with other addresses (greater than 0x10000 ) also but it is throwing the same error.
Is there a way to get over this ?
Thanks
Vaibhav Jain
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