Re: [Qemu-devel] [PATCH] block: Fix max nb_sectors in bdrv_make_zero

[Markus Armbruster]

Fam Zheng <address@hidden> writes:

> In bdrv_rw_co we report -EINVAL for nb_sectors > INT_MAX /
> BDRV_SECTOR_SIZE, so a caller shouldn't exceed it.

It's not obvious to me why we do that there.  iovec member iov_len is
size_t, not int.

> Signed-off-by: Fam Zheng <address@hidden>
> ---
>  block.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/block.c b/block.c
> index dacd881..5513379 100644
> --- a/block.c
> +++ b/block.c
> @@ -2790,8 +2790,8 @@ int bdrv_make_zero(BlockDriverState *bs, 
> BdrvRequestFlags flags)
>          if (nb_sectors <= 0) {
>              return 0;
>          }
> -        if (nb_sectors > INT_MAX) {
> -            nb_sectors = INT_MAX;
> +        if (nb_sectors > INT_MAX / BDRV_SECTOR_SIZE) {
> +            nb_sectors = INT_MAX / BDRV_SECTOR_SIZE;
>          }
>          ret = bdrv_get_block_status(bs, sector_num, nb_sectors, &n);
>          if (ret < 0) {

Noticed while checkout out bdrv_get_block_status(): function comment of
bdrv_co_get_block_status() claims it returns true/false.  It doesn't.