lkml.org 
[lkml]   [2019]   [Jun]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    SubjectRe: [PATCH V31 07/25] kexec_file: Restrict at runtime if the kernel is locked down
    From
    Date
    Hi Matthew,

    On Mon, 2019-06-24 at 14:06 -0700, Matthew Garrett wrote:
    > On Sun, Jun 23, 2019 at 6:52 PM Dave Young <dyoung@redhat.com> wrote:
    > >
    > > On 06/21/19 at 01:18pm, Matthew Garrett wrote:
    > > > I don't think so - we want it to be possible to load images if they
    > > > have a valid signature.
    > >
    > > I know it works like this way because of the previous patch. But from
    > > the patch log "When KEXEC_SIG is not enabled, kernel should not load
    > > images", it is simple to check it early for !IS_ENABLED(CONFIG_KEXEC_SIG) &&
    > > kernel_is_locked_down(reason, LOCKDOWN_INTEGRITY) instead of depending
    > > on the late code to verify signature. In that way, easier to
    > > understand the logic, no?
    >
    > But that combination doesn't enforce signature validation? We can't
    > depend on !IS_ENABLED(CONFIG_KEXEC_SIG_FORCE) because then it'll
    > enforce signature validation even if lockdown is disabled.

    I agree with Dave.  There should be a stub lockdown function to
    prevent enforcing lockdown when it isn't enabled.

    Mimi

    \
     
     \ /
      Last update: 2019-06-24 23:28    [W:4.203 / U:0.032 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site