Re: [PATCH] btrfs-progs: common: make sure that qgroup id is in range

[David Sterba <dsterba@suse.cz>]

On Mon, Mar 15, 2021 at 03:56:38PM +0000, Sidong Yang wrote:
> When user assign qgroup with qgroup id that is too big to exceeds
> range and invade level value, and it works without any error. but
> this action would be make undefined error. this code make sure that
> qgroup id doesn't exceed range(0 ~ 2^48-1).
> 
> Signed-off-by: Sidong Yang <realwakka@gmail.com>
> ---
>  common/utils.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/common/utils.c b/common/utils.c
> index 57e41432..a2f72550 100644
> --- a/common/utils.c
> +++ b/common/utils.c
> @@ -727,6 +727,8 @@ u64 parse_qgroupid(const char *p)
>  		id = strtoull(p, &ptr_parse_end, 10);
>  		if (ptr_parse_end != ptr_src_end)
>  			goto path;
> +		if (id >> BTRFS_QGROUP_LEVEL_SHIFT)
> +			goto err;

Please add a helper that validates the id or use btrfs_qgroup_level and
check that level is 0 if that makes sense in the context of the call.