[PATCH v2 1/2] Fix corner case in bad block table handling.

[Frieder Schrempf]

Hi stable maintainers,

On 06.04.21 03:47, Yoshio Furuyama wrote:
> From: "Doyle, Patrick" <pdoyle at irobot.com>
> 
> In the unlikely event that both blocks 10 and 11 are marked as bad (on a
> 32 bit machine), then the process of marking block 10 as bad stomps on
> cached entry for block 11.  There are (of course) other examples.
> 
> Signed-off-by: Patrick Doyle <pdoyle at irobot.com>
> Reviewed-by: Richard Weinberger <richard at nod.at>

We have systems on which this patch fixes real failures. Could you
please add the upstream patch fd0d8d85f723 ("mtd: nand: bbt: Fix corner
case in bad block table handling") to the stable queues for 4.19, 5.4, 5.10?

Thanks!

Cc: stable at vger.kernel.org
Fixes: 9c3736a3de21 ("mtd: nand: Add core infrastructure to deal with
NAND devices")

> ---
>  drivers/mtd/nand/bbt.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/mtd/nand/bbt.c b/drivers/mtd/nand/bbt.c
> index 044adf913854..64af6898131d 100644
> --- a/drivers/mtd/nand/bbt.c
> +++ b/drivers/mtd/nand/bbt.c
> @@ -123,7 +123,7 @@ int nanddev_bbt_set_block_status(struct nand_device *nand, unsigned int entry,
>  		unsigned int rbits = bits_per_block + offs - BITS_PER_LONG;
>  
>  		pos[1] &= ~GENMASK(rbits - 1, 0);
> -		pos[1] |= val >> rbits;
> +		pos[1] |= val >> (bits_per_block - rbits);
>  	}
>  
>  	return 0;