Re: [PATCH 4/4] Allow unprivileged chroot when safe

[Andy Lutomirski]

On Tue, Jan 17, 2012 at 8:23 AM, Oleg Nesterov <oleg@xxxxxxxxxx> wrote:
> On 01/15, Andy Lutomirski wrote:
>>
>> Chroot can easily be used to subvert setuid programs.  If no_new_privs,
>> then setuid programs don't gain any privilege, so allow chroot.
>>
>> ...
>>
>> +     if (!(current->no_new_privs && !is_chrooted) &&
>> +         !capable(CAP_SYS_CHROOT))
>
> I must have missed something. How no_new_privs can help if fs->users != 1 ?

Whoops.  That needs fixing.

--Andy
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