Re: [PATCH] diskquota: 32bit quota tools on 64bit architectures

[Andi Kleen <ak@suse.de>]

Vasily Tarasov <vtaras@openvz.org> writes:

> OpenVZ Linux kernel team has discovered the problem 
> with 32bit quota tools working on 64bit architectures.
> In 2.6.10 kernel sys32_quotactl() function was replaced by sys_quotactl() with
> the comment "sys_quotactl seems to be 32/64bit clean, enable it for 32bit"
> However this isn't right. Look at if_dqblk structure:
> 
> struct if_dqblk {
>         __u64 dqb_bhardlimit;
>         __u64 dqb_bsoftlimit;
>         __u64 dqb_curspace;
>         __u64 dqb_ihardlimit;
>         __u64 dqb_isoftlimit;
>         __u64 dqb_curinodes;
>         __u64 dqb_btime;
>         __u64 dqb_itime;
>         __u32 dqb_valid;
> };
> 
> For 32 bit quota tools sizeof(if_dqblk) == 0x44.
> But for 64 bit kernel its size is 0x48, 'cause of alignment!
> Thus we got a problem.
> Attached patch reintroduce sys32_quotactl() function,
> that handles the situation.

Thanks. But the code should be probably common somewhere in fs/*, not 
duplicated.

-Andi