On Tue, 2017-11-14 at 13:38 +0100, Greg Kroah-Hartman wrote: > On Tue, Nov 14, 2017 at 07:21:38AM -0500, Mimi Zohar wrote: > > On Mon, 2017-11-13 at 14:09 -0800, Linus Torvalds wrote: > > > On Mon, Nov 13, 2017 at 1:44 PM, David Howells <dhowells@xxxxxxxxxx> wrote: > > > > > > > > Whilst that may be true, we either have to check signatures on every bit of > > > > firmware that the appropriate driver doesn't say is meant to be signed or not > > > > bother. > > > > > > I vote for "not bother". > > > > > > Seriously, if you have firmware in /lib/firmware, and you don't trust > > > it, what the hell are you doing? > > > > I might "trust" the files in /lib/firmware, but I also want to make > > sure that they haven't changed. File signatures provide file > > provenance and integrity guarantees. > > Then "verify" them with signatures that you generate yourself. Like > dm-verify does for the partition that you put the firmware on. The discussion, here, is in the context of the "lockdown" patch set, without IMA-appraisal configured. Kernel modules and the kexec kernel image require file signatures in lockdown mode. An equivalent method of requiring file signatures for firmware (without IMA-appraisal) does not exist. I posted the patch [RFC PATCH v2] "fw_lockdown: new micro LSM module to prevent loading unsigned firmware". The patch and discussion can be found here - (https://lkml.org/lkml/2017/11/13/217). Mimi -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
