[kernel-hardening] [PATCH v2 2/5] time: mark syscore_ops as __ro_after_init

Jess Frazelle
2017-02-11T01:37:55Z

Marked syscore_ops structs as __ro_after_init when register_syscore_ops was
called only during init. Most of the caller functions were already annotated as
__init.
unregister_syscore_ops() was never called on these ops.
This protects the data structure from accidental corruption.

Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jess Frazelle <me@jessfraz.com>
Acked-by: Rik van Riel <riel@redhat.com>
---
kernel/time/sched_clock.c | 2 +-
kernel/time/timekeeping.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/time/sched_clock.c b/kernel/time/sched_clock.c
index a26036d37a38..5df2fc07300b 100644
--- a/kernel/time/sched_clock.c
+++ b/kernel/time/sched_clock.c
@@ -289,7 +289,7 @@ static void sched_clock_resume(void)
rd->read_sched_clock = cd.actual_read_sched_clock;
}

-static struct syscore_ops sched_clock_ops = {
+static struct syscore_ops sched_clock_ops __ro_after_init = {
.suspend = sched_clock_suspend,
.resume = sched_clock_resume,
};
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index db087d7e106d..467e3021723a 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -1756,7 +1756,7 @@ int timekeeping_suspend(void)
}

/* sysfs resume/suspend bits for timekeeping */
-static struct syscore_ops timekeeping_syscore_ops = {
+static struct syscore_ops timekeeping_syscore_ops __ro_after_init = {
.resume = timekeeping_resume,
.suspend = timekeeping_suspend,
};
--
2.11.0