Re: [PATCH 4/6] BC: user interface (syscalls)

[Chandra Seetharaman <sekharan@us.ibm.com>]

On Wed, 2006-08-23 at 15:06 +0400, Kirill Korotaev wrote:
<snip>

> +asmlinkage long sys_set_bclimit(uid_t id, unsigned long resource,
> +		unsigned long *limits)
> +{
> +	int error;
> +	unsigned long flags;
> +	struct beancounter *bc;
> +	unsigned long new_limits[2];
> +
> +	error = -EPERM;
> +	if(!capable(CAP_SYS_RESOURCE))
> +		goto out;
> +
> +	error = -EINVAL;
> +	if (resource >= BC_RESOURCES)
> +		goto out;
> +
> +	error = -EFAULT;
> +	if (copy_from_user(&new_limits, limits, sizeof(new_limits)))
> +		goto out;
> +
> +	error = -EINVAL;
> +	if (new_limits[0] > BC_MAXVALUE || new_limits[1] > BC_MAXVALUE)
> +		goto out;
> +
> +	error = -ENOENT;
> +	bc = beancounter_findcreate(id, 0);
> +	if (bc == NULL)
> +		goto out;
> +
> +	spin_lock_irqsave(&bc->bc_lock, flags);
> +	bc->bc_parms[resource].barrier = new_limits[0];
> +	bc->bc_parms[resource].limit = new_limits[1];

	No check for barrier <= limit
> +	spin_unlock_irqrestore(&bc->bc_lock, flags);
> +
> +	put_beancounter(bc);
> +	error = 0;
> +out:
> +	return error;
> +}
<snip>
-- 

----------------------------------------------------------------------
    Chandra Seetharaman               | Be careful what you choose....
              - sekharan@us.ibm.com   |      .......you may get it.
----------------------------------------------------------------------