Re: NGROUPS 2.6.2rc2

[Tim Hockin <thockin@hockin.org>]

On Tue, Jan 27, 2004 at 04:46:15PM -0800, Andrew Morton wrote:
> > Attached is a patch to remove the NGROUPS limit (again).
> +/* export the group_info to a user-space array */
> +static int groups_to_user(gid_t *grouplist, struct group_info __user *info)

> This had me thorougly confused for a while ;) The __user tag here should
> apply to grouplist, not to info.

indeed.

> +static int groups16_to_user(old_gid_t __user *grouplist,
> +    struct group_info *info)
> +{
> +	int i;
> +	old_gid_t group;
> +
> +	if (info->ngroups > TASK_SIZE/sizeof(group))
> +		return -EFAULT;
> +	if (!access_ok(VERIFY_WRITE, grouplist, info->ngroups * sizeof(group)))
> +		return -EFAULT;
> 
> Why are many functions playing with TASK_SIZE?

Not sure - I thought it was maybe a paranoid check, Rusty included it in his
version of a similar patch a while ago.

> +extern asmlinkage long sys_setgroups(int gidsetsize, gid_t *grouplist);
> 
> rant.  We have soooo many syscalls declared in .c files.  We had a bug due
> to this a while back.  Problem is, we have no anointed header in which to
> place them.  include/linux/syscalls.h would suit.  And unistd.h for
> arch-specific syscalls.  But that's not appropriate to this patch.

Agreed.