x86: Restrict MSR access when securelevel is set
authorMatthew Garrett <mjg59@srcf.ucam.org>
Fri, 8 Feb 2013 19:12:13 +0000 (11:12 -0800)
committerBen Hutchings <ben@decadent.org.uk>
Tue, 2 May 2017 15:21:44 +0000 (15:21 +0000)
commitbc946ffb3d8f806ffc57e78c98b933837fcbaaa5
treecb7a123556d040439d839bae1db7d33630c3f2a0
parent050ce0a441a1ca322fc320b51f370b77491dac84
x86: Restrict MSR access when securelevel is set

Permitting write access to MSRs allows userspace to modify the running
kernel. Prevent this if securelevel has been set. Based on a patch by Kees
Cook.

Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Matthew Garrett <mjg59@srcf.ucam.org>
Gbp-Pq: Topic features/all/securelevel
Gbp-Pq: Name x86-restrict-msr-access-when-securelevel-is-set.patch
arch/x86/kernel/msr.c