Re: different capability from different namespace required for prctl_set_mm_exe_file

From: Greg KH
Date: Tue Sep 25 2018 - 13:37:52 EST

On Tue, Sep 25, 2018 at 01:26:55PM -0400, Tong Zhang wrote:
> Kernel Version: 4.18.5
> Problem Description:
> We discovered inconsistent check when using prctl_set_mm_exe_file(), which is used to setup exe file link.
> It is required to have capable(CAP_SYS_RESOURCE) in prctl_set_mm().
> while ns_capable(CAP_SYS_ADMIN) in prctl_set_mm_map().
> There are two differences:
> 1)requiring capability from: user namespace, init namespace.
> 2)capability bit required is different

Can you submit a patch showing what you think is the correct fix here?


greg k-h