Re: MTD: How to get actual image size from MTD partition

From: Richard Weinberger
Date: Fri Jul 16 2021 - 12:27:02 EST


----- Ursprüngliche Mail -----
> Von: "Greg KH" <greg@xxxxxxxxx>
> An: "Pintu Agarwal" <pintu.ping@xxxxxxxxx>
> CC: "linux-kernel" <linux-kernel@xxxxxxxxxxxxxxx>, "linux-mtd" <linux-mtd@xxxxxxxxxxxxxxxxxxx>, "linux-fsdevel"
> <linux-fsdevel@xxxxxxxxxxxxxxx>, "Phillip Lougher" <phillip@xxxxxxxxxxxxxxx>, "Sean Nyekjaer" <sean@xxxxxxxxxx>,
> "Kernelnewbies" <kernelnewbies@xxxxxxxxxxxxxxxxx>, "richard" <richard@xxxxxx>
> Gesendet: Freitag, 16. Juli 2021 17:41:01
> Betreff: Re: MTD: How to get actual image size from MTD partition

> On Fri, Jul 16, 2021 at 12:12:41PM +0530, Pintu Agarwal wrote:
>> Hi,
>>
>> Our ARM32 Linux embedded system consists of these:
>> * Linux Kernel: 4.14
>> * Processor: Qualcomm Arm32 Cortex-A7
>> * Storage: NAND 512MB
>> * Platform: Simple busybox
>> * Filesystem: UBIFS, Squashfs
>> * Consists of nand raw partitions, squashfs ubi volumes.
>>
>> My requirement:
>> To find the checksum of a real image in runtime which is flashed in an
>> MTD partition.
>
> Try using the dm-verity module for ensuring that a block device really
> is properly signed before mounting it. That's what it was designed for
> and is independent of the block device type.

MTDs are not block devices. :-)

Thanks,
//richard