[U-Boot] U-Boot TFTP protection

[Lukasz Majewski <lukma@denx.de>]

Hi Stefan,

> Hello,
> We have been looking at protecting U-Boot from (malicious) TFTP
> overwrites. We want to do this after our ARMv7 U-Boot has relocated.
> 
> The memory map looks like this (I hope):
> 
> ---------------------------  Top of DRAM
> | U-Boot (Protected)
> | -------------------------- U_Boot_start
> | Heap (Protected)
> | -------------------------- Start_Heap = U_Boot_start - Heap_Size
> | Stack (Protected)
> | -------------------------- Start_Stack = Start_Heap - Stack_Size
> | Buffers (Protected)
> | -------------------------- ???
> | Free DRAM (Not Protected)
> ---------------------------  Start of DRAM
> 
> I seem to get lost in the code trying to find possible buffers, can
> you please give a hint how I can find the address "???"

By default the tftp writes its data to the address pointed by the
"loadaddr" env variable.

printenv loadaddr

> 
> Best Regards,
> Stefan
> 
> _______________________________________________
> U-Boot mailing list
> U-Boot at lists.denx.de
> https://lists.denx.de/listinfo/u-boot




Best regards,

Lukasz Majewski

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