On Thu, 25 May 2017 13:50:20 +0900
Masahiro Yamada <[email protected]> wrote:
> Drivers are supposed to set correct ecc->{size,strength,bytes} before
> calling nand_scan_tail(), but it does not complain about ecc->total
> bigger than oobsize.
>
> In this case, chip->scan_bbt() crashes due to memory corruption, but
> it is hard to debug. It would be kind to fail it earlier with a clear
> message.
>
> Signed-off-by: Masahiro Yamada <[email protected]>
Applied to nand/next.
Thanks,
Boris
> ---
>
> I was actually hit by this case.
>
> I wasted half a day until I figured out my coding mistake in my
> Denali driver. It will be helpful to check this in NAND core.
>
>
> drivers/mtd/nand/nand_base.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
> index f4d686192717..14d6a5aa3ee8 100644
> --- a/drivers/mtd/nand/nand_base.c
> +++ b/drivers/mtd/nand/nand_base.c
> @@ -4970,6 +4970,11 @@ int nand_scan_tail(struct mtd_info *mtd)
> goto err_free;
> }
> ecc->total = ecc->steps * ecc->bytes;
> + if (ecc->total > mtd->oobsize) {
> + WARN(1, "Total number of ECC bytes exceeded oobsize\n");
> + ret = -EINVAL;
> + goto err_free;
> + }
>
> /*
> * The number of bytes available for a client to place data into
