fec6c20b57
A common flaw in UEFI systems is a refusal to POST triggered by a malformed boot variable. Once in this state, machines may only be restored by reflashing their firmware with an external hardware device. While this is obviously a firmware bug, the serious nature of the outcome suggests that operating systems should filter their variable writes in order to prevent a malicious user from rendering the machine unusable. Signed-off-by: Matthew Garrett <mjg@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>