From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mimi Zohar Subject: Re: [PATCH V31 07/25] kexec_file: Restrict at runtime if the kernel is locked down Date: Mon, 24 Jun 2019 21:46:03 -0400 Message-ID: <1561427163.4340.98.camel@linux.ibm.com> References: <20190326182742.16950-1-matthewgarrett@google.com> <20190326182742.16950-8-matthewgarrett@google.com> <20190621064340.GB4528@localhost.localdomain> <20190624015206.GB2976@dhcp-128-65.nay.redhat.com> <1561411657.4340.70.camel@linux.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Matthew Garrett Cc: Dave Young , James Morris , Jiri Bohac , Linux API , kexec@lists.infradead.org, Linux Kernel Mailing List , David Howells , LSM List , Andy Lutomirski List-Id: linux-api@vger.kernel.org On Mon, 2019-06-24 at 17:02 -0700, Matthew Garrett wrote: > On Mon, Jun 24, 2019 at 2:27 PM Mimi Zohar wrote: > > > I agree with Dave. There should be a stub lockdown function to > > prevent enforcing lockdown when it isn't enabled. > > Sorry, when what isn't enabled? If no LSMs are enforcing lockdown then > the check will return 0. The goal here is for distributions to be able > to ship a kernel that has CONFIG_KEXEC_SIG=y, CONFIG_KEXEC_SIG_FORCE=n > and at runtime be able to enforce a policy that requires signatures on > kexec payloads. Never mind, the call can't be moved earlier.