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Re: Plug-and-wipe and Secure Boot semantics
From: Florian Weimer <fweimer () redhat com>
Date: Tue, 18 Dec 2012 15:52:50 +0100

On 12/18/2012 03:41 PM, Greg KH wrote:
On Tue, Dec 18, 2012 at 01:46:47PM +0100, Florian Weimer wrote:
Some UEFI machines seem to boot from USB by default, without any
prompting, probably assuming that a signed boot loader cannot cause
any damage.

Specific model name(s) please?

Lenovo M72e 0896A9G

This is a business-class Windows 8 machine which comes with a Windows 8 logo sticker, so Secure Boot was enabled in the factory (and my testing reflected that). I'm not sure if the type number encodes that—Lenovo surely offers essentially the same hardware with Secure Boot disabled by default, so that customers can install Windows 7 more easily.

Most signed Linux boot loaders only verify the kernel (and,
indirectly, code that's loaded into the kernel), but not the
initrd contents.

Given that there is only one public signed Linux boot loader, saying
"most" is a bit odd here :)

Uhm, aren't there a couple of them in circulation?

The Fedora 18 TC3 installer boots on the machine mentioned above, in the factory default configuration. Previous installer versions showed a Secure Boot error message. I've run into an installer bug, though:

Florian Weimer / Red Hat Product Security Team

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