Re: [PATCH u-boot 2/4] cmd: mvebu/bubt: Validate EXT_CSD[179] eMMC register in mmc_burn_image()

+ Martin

On Thursday 13 April 2023 23:10:55 Pali Rohár wrote:

When determining eMMC boot partition for a bootloader, validate that EXT_CSD[179] eMMC register is set to recognized value.

This prevent situation that EXT_CSD[179] Boot Enable value is improperly parsed and passed into EXT_CSD[179] Partition Access.

Signed-off-by: Pali Rohár pali@kernel.org

cmd/mvebu/bubt.c | 24 ++++++++++++++++++++++-- 1 file changed, 22 insertions(+), 2 deletions(-)

diff --git a/cmd/mvebu/bubt.c b/cmd/mvebu/bubt.c index ca24a5c1c4ba..b8fe7c7a1461 100644 --- a/cmd/mvebu/bubt.c +++ b/cmd/mvebu/bubt.c @@ -223,9 +223,29 @@ static int mmc_burn_image(size_t image_size) orig_part = mmc->block_dev.hwpart; #endif

• part = EXT_CSD_EXTRACT_BOOT_PART(mmc->part_config);
• if (part == 7)

• if (mmc->part_config == MMCPART_NOAVAILABLE) { part = 0;
• } else {

• switch (EXT_CSD_EXTRACT_BOOT_PART(mmc->part_config)) {
  

• case 0: /* Booting from this eMMC device is disabled */
  

• 	printf("Error - Booting from this eMMC device is disabled\n");
  

• 	printf("Hint: Use 'mmc partconf' command to choose boot partition\n");
  

• 	return -ENODEV;
  

• case 1: /* Boot partition 1 is used for booting */
  

• 	part = 1;
  

• 	break;
  

• case 2: /* Boot partition 2 is used for booting */
  

• 	part = 2;
  

• 	break;
  

• case 7: /* User area is used for booting */
  

• 	part = 0;
  

• 	break;
  

• default: /* Other values are reserved / unsupported */
  

• 	printf("Error - This eMMC device has configured Reserved boot option\n");
  

• 	printf("Hint: Use 'mmc partconf' command to choose boot partition\n");
  

• 	return -ENODEV;
  

• }
  

• }

#ifdef CONFIG_BLK err = blk_dselect_hwpart(blk_desc, part); -- 2.20.1