Re: [PATCH 2/2] add some safety checks for label store interface of flash dev in sysfs

[Junhui Tang]

Seems something wrong
when  size = SB_LABEL_SIZE and   u->label[size - 1] != '\n'
please check again.

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Tang Junhui
Forever me is me
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Dongbo Cao <cdbdyx@xxxxxxx> ä2018å9æ14æåä äå6:13åéï
>
> do some checks on the label's length and ending.
>
> Signed-off-by: Dongbo Cao <cdbdyx@xxxxxxx>
> ---
>  drivers/md/bcache/sysfs.c | 9 ++++++++-
>  1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c
> index e64c718f..cce793ef 100644
> --- a/drivers/md/bcache/sysfs.c
> +++ b/drivers/md/bcache/sysfs.c
> @@ -447,8 +447,15 @@ STORE(__bch_flash_dev)
>         }
>
>         if (attr == &sysfs_label) {
> +               if (size > SB_LABEL_SIZE)
> +                       return -EINVAL;
>                 memcpy(u->label, buf, SB_LABEL_SIZE);
> -               bch_uuid_write(d->c);
> +               if (size < SB_LABEL_SIZE)
> +                       u->label[size] = '\0';
> +               if (size && u->label[size - 1] == '\n')
> +                       u->label[size - 1] = '\0';
> +               if(d->c)
> +                       bch_uuid_write(d->c);
>         }
>
>         if (attr == &sysfs_unregister) {
> --
> 2.17.1
>
>