latent_entropy: Mark functions with __latent_entropy

The __latent_entropy gcc attribute can be used only on functions and
variables.  If it is on a function then the plugin will instrument it for
gathering control-flow entropy. If the attribute is on a variable then
the plugin will initialize it with random contents.  The variable must
be an integer, an integer array type or a structure with integer fields.

These specific functions have been selected because they are init
functions (to help gather boot-time entropy), are called at unpredictable
times, or they have variable loops, each of which provide some level of
latent entropy.

Signed-off-by: Emese Revfy <re.emese@gmail.com>
[kees: expanded commit message]
Signed-off-by: Kees Cook <keescook@chromium.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index 32bf6f75a8fe..2d47980a1bc4 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -1633,7 +1633,7 @@ static inline void __run_timers(struct timer_base *base)
 /*
  * This function runs timers and the timer-tq in bottom half context.
  */
-static void run_timer_softirq(struct softirq_action *h)
+static __latent_entropy void run_timer_softirq(struct softirq_action *h)
 {
         struct timer_base *base = this_cpu_ptr(&timer_bases[BASE_STD]);