First time accepted submitter YurB writes "Matthew Garrett, a Linux kernel developer who was investigating the recent Linux-on-Samsung-in-UEFI-mode problem, has bricked a Samsung laptop using a test userspace program in Windows. The most fascinating part of the story is on what is actually causing the firmware boot failure: 'Unfortunately, it turns out that some Samsung laptops will fail to boot if too much of the [UEFI] variable storage space is used. We don't know what "too much" is yet, but writing a bunch of variables from Windows is enough to trigger it. I put some sample code here — it writes out 36 variables each containing a kilobyte of random data. I ran this as an administrator under Windows and then rebooted the system. It never came back.'"
hypnosec writes "The Linux Foundation's UEFI Secure Boot pre-bootloader for independent Linux distros and software developers has finally been released. Announcing the release of the secure boot system James Bottomley noted that the signed pre-bootloader was delivered by Microsoft on February 6th. Bottomley has released two validated files: PreLoader.efi and HashTool.efi. Bottomley has also created a bootable mini-USB image that provides 'an EFI shell where the kernel should be and uses Gummiboot to boot.' Just last week the pre-bootloader had to be rewritten to accommodate booting of all versions of Linux."