eddystone_flash_access_flags makes HardFault

[wanghuayuan0]

Hi tony, I think I found a little problem of function eddystone_flash_access_flags when I using this SDK at nrf51422

 ...
        case EDDYSTONE_FLASH_ACCESS_READ:
            err_code = pstorage_load((uint8_t*)p_flags,
                                     &flags_handle,
                                     FLASH_BLOCK_SIZE,
                                     0);
            RETURN_IF_ERROR(err_code);
            break;
...

The size of eddystone_flash_flags_t is 8, and loading size is FLASH_BLOCK_SIZE(32). It will damage other data in ram

[tonywu-nordicsemi]

Hello! Sorry I don't quite understand your question, would you mind clarifying? Thanks!

[wanghuayuan0]

Hi, Tony,

Sorry for my poor english and unclear description T^T.

I mean, the FLASH_BLOCK_SIZE is 32:

#ifndef EDDYSTONE_FLASH_H
#define EDDYSTONE_FLASH_H

#include <stdint.h>
#include <stdbool.h>
#include "ble_ecs.h"
#include "pstorage.h"
#include "eddystone_app_config.h"

#define FLASH_BLOCK_SIZE    32  //Minimum size 32, for ECDH key storage

and the size of eddystone_flash_flags_t is 8

typedef struct
{
    bool    factory_state;                                  //If this flag is true, then use factory default frame configs
    bool    slot_is_empty[APP_MAX_ADV_SLOTS];
    uint8_t padding[ WORD_SIZE - ((APP_MAX_ADV_SLOTS+1) % WORD_SIZE) ];    //Add padding up to the next multiple of WORD_SIZE
} eddystone_flash_flags_t; //TODO: talk about having the flags struct match flash block size here

you don't match the flags struct to flash block size this version.

when calling this code snippet

case EDDYSTONE_FLASH_ACCESS_READ:
            err_code = pstorage_load((uint8_t*)p_flags,
                                     &flags_handle,
                                     FLASH_BLOCK_SIZE,
                                     0);
            RETURN_IF_ERROR(err_code);
            break;

32 bytes data in flash will load to point p_flags, but there are only 8 bytes expected , the unnecessary 24 bytes may overwrite something in ram and cause hardfault..

I tested this SDK on 52DK, it performed will, but it caused hardfault on 51DK

Thanks