<br><br><div class="gmail_quote">On Thu, Oct 6, 2011 at 11:28 AM, Mulyadi Santosa <span dir="ltr"><<a href="mailto:mulyadi.santosa@gmail.com">mulyadi.santosa@gmail.com</a>></span> wrote:<br><blockquote style="margin: 0px 0px 0px 0.8ex; padding-left: 1ex; border-left-color: rgb(204, 204, 204); border-left-width: 1px; border-left-style: solid;" class="gmail_quote">
Hi...<br>
<div class="im"><br>
On Thu, Oct 6, 2011 at 02:34, Vaibhav Jain <<a href="mailto:vjoss197@gmail.com">vjoss197@gmail.com</a>> wrote:<br>
> Hi,<br>
><br>
> I am trying to run a program that scans memory from a given physical address<br>
> using /dev/mem.<br>
> It uses mmap to map physical address from /dev/mem. So to start with I used<br>
> /proc/iomem to look up the<br>
> physical memory mapping and found the address 00010000 to be the starting<br>
> address for System ram. But whenever I<br>
> provide this address to the program it throws an error of "Operation not<br>
> permitted".<br>
<br>
</div>Probably this could also due to mmap NULL dereferencing protection (at<br>
least that's how I name it :) )<br>
<br>
By default, the lowest 65536 byte (10000 in hex) is protected from<br>
mapping etc. It practically render such null dererefencing useless.<br>
<font color="#888888"><br>
<br>
--<br>
regards,<br>
<br>
Mulyadi Santosa<br>
Freelance Linux trainer and consultant<br>
<br>
blog: <a href="http://the-hydra.blogspot.com" target="_blank">the-hydra.blogspot.com</a><br>
training: <a href="http://mulyaditraining.blogspot.com" target="_blank">mulyaditraining.blogspot.com</a><br>
</font></blockquote></div><div><br>Hi,</div><div> </div><div>I tried the same with other addresses (greater than 0x10000 ) also but it is throwing the same error.</div><div>Is there a way to get over this ?</div><div> </div>
<div>Thanks</div><div>Vaibhav Jain</div><div> </div><div> </div>