[U-Boot] secure embedded linux system

[Wolfgang Denk]

Dear Mahendra Dobariya,

In message <BAY176-W171CCC856593BA0F7380DC90240 at phx.gbl> you wrote:
>
> hello,,I am from India.I am electronics hobbyist.currently I am using
> beaglebone black in my project.and I am afraid of security of linux
> systemits quite easy to copy or modify data from linux system if it
> has physical access.lets say ,I have BBB , and I boot it from
> external device(like external mmc ). and mount internal emmc then
> modify shadow file. and then boot from internal Emmc. now I will get
> root access , and I can modify anything on the system.

If you cannot prevent physical access, you cannot prevent one from
taking full control over your hardware.  If needed, I'll attach a JTAG
debugger and run my own version of U-Boot that circumvents all security
measures you installed in yours.

Best regards,

Wolfgang Denk

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