[U-Boot] [PATCH 3/4] fs: prevent overwriting reserved memory

[Heinrich Schuchardt]

On 11/13/18 6:47 AM, Simon Goldschmidt wrote:
> On Tue, Nov 13, 2018 at 3:23 AM Fabio Estevam <festevam at gmail.com> wrote:
>>
>> Hi Simon,
>>
>> On Mon, Nov 12, 2018 at 7:25 PM Simon Goldschmidt
>> <simon.k.r.goldschmidt at gmail.com> wrote:
>>
>>> diff --git a/fs/fs.c b/fs/fs.c
>>> index adae98d021..4baf6b1c39 100644
>>> --- a/fs/fs.c
>>> +++ b/fs/fs.c
>>> @@ -428,13 +428,57 @@ int fs_size(const char *filename, loff_t *size)
>>>         return ret;
>>>  }
>>>
>>> -int fs_read(const char *filename, ulong addr, loff_t offset, loff_t len,
>>> -           loff_t *actread)
>>> +#ifdef CONFIG_LMB
>>
>> Unrelated to your series, but I was wondering if we could get rid of
>> the CONFIG_LMB option.
>>
>> As far as I can see all the architectures define it, the only
>> exception being arch/sh.
>>
>> If you agree I can send a patch after your series gets applied that
>> removes CONFIG_LMB.
> 
> Sure, that would clean things up.
> 
> Simon
> 

NAK

This patch-series does not provide what is needed. With
odroid-c2_defconfig I get

fdt list /reserved-memory/secmon at 10000000
reserved-memory {
        secmon at 10000000 {
                reg = <0x00000000 0x10000000 0x00000000 0x00200000>;
                no-map;
        };
};

=> load mmc 0:1 0x10000000 dtb
22925 bytes read in 8 ms (2.7 MiB/s)

So now I have successfully overwritten the secure monitor. Urrgh.

As you have observed load is still writing into a memory area that is
reserved by the device-tree.

Please, iterate over the device tree to ensure that nothing is loaded
into a reserved memory area. Do not expect board files to do anything
but create the reserve-memory entry in the device tree.

Best regards

Heinrich