x86: Lock down IO port access when securelevel is enabled
authorMatthew Garrett <mjg59@srcf.ucam.org>
Thu, 8 Mar 2012 15:35:59 +0000 (10:35 -0500)
committerAurelien Jarno <aurel32@debian.org>
Fri, 2 Mar 2018 07:52:22 +0000 (07:52 +0000)
commited79c5eeebeb598db80d832eab61d11f1604c058
tree443c1d99a923e1efbe619f678435ddd285266281
parent93f32d8fd664ba9ef4fb4407d917aed26e740de8
x86: Lock down IO port access when securelevel is enabled

IO port access would permit users to gain access to PCI configuration
registers, which in turn (on a lot of hardware) give access to MMIO register
space. This would potentially permit root to trigger arbitrary DMA, so lock
it down when securelevel is set.

Signed-off-by: Matthew Garrett <mjg59@srcf.ucam.org>
Gbp-Pq: Topic features/all/securelevel
Gbp-Pq: Name x86-lock-down-io-port-access-when-securelevel-is-ena.patch
arch/x86/kernel/ioport.c
drivers/char/mem.c