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)
committerSalvatore Bonaccorso <carnil@debian.org>
Fri, 2 Dec 2016 05:35:22 +0000 (05:35 +0000)
commit1d785a3dc163bc71933b64e16498604e95b41eac
tree9d8031900e2757b6b9183d4f6ab254c83642838b
parent430b1a1249e904429c2c86c3338e5a392265ad5c
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