efi: Validate UEFI boot variables
authorMatthew Garrett <mjg@redhat.com>
Mon, 30 Apr 2012 20:11:30 +0000 (16:11 -0400)
committerVarun Wadekar <vwadekar@nvidia.com>
Mon, 14 May 2012 12:35:57 +0000 (17:35 +0530)
commitbd4ed9bbad88bdd1b8c5a19edfcc0d2d23069c96
tree963c9585528e1d7a186eced23ef1d589aaaf9c06
parentef5abc5692d188c72b581d8124bb6d5660511325
efi: Validate UEFI boot variables

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>
drivers/firmware/efivars.c