From mboxrd@z Thu Jan 1 00:00:00 1970 Reply-To: kernel-hardening@lists.openwall.com Date: Sat, 18 Jun 2016 11:03:20 -0700 From: Kees Cook Message-ID: <20160618180320.GA862@www.outflux.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Subject: [kernel-hardening] [PATCH] latent_entropy: provide userspace visibility To: kernel-hardening@lists.openwall.com Cc: Emese Revfy List-ID: This is just a toy to look at the latent_entropy value as it changes from userspace. Not intended for actual use... Signed-off-by: Kees Cook --- kernel/ksysfs.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c index 152da4a48867..64aed735098a 100644 --- a/kernel/ksysfs.c +++ b/kernel/ksysfs.c @@ -180,6 +180,15 @@ static ssize_t rcu_normal_store(struct kobject *kobj, KERNEL_ATTR_RW(rcu_normal); #endif /* #ifndef CONFIG_TINY_RCU */ +#ifdef CONFIG_GCC_PLUGIN_LATENT_ENTROPY +static ssize_t latent_entropy_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + return sprintf(buf, "0x%08llx\n", latent_entropy); +} +KERNEL_ATTR_RO(latent_entropy); +#endif + /* * Make /sys/kernel/notes give the raw contents of our kernel .notes section. */ @@ -225,6 +234,9 @@ static struct attribute * kernel_attrs[] = { &rcu_expedited_attr.attr, &rcu_normal_attr.attr, #endif +#ifdef CONFIG_GCC_PLUGIN_LATENT_ENTROPY + &latent_entropy_attr.attr, +#endif NULL }; -- 2.7.4 -- Kees Cook Chrome OS & Brillo Security