From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Sun, 29 Apr 2018 10:35:53 +0000 (+0200)
Subject: 4.9-stable patches
X-Git-Tag: v4.16.7~41
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=4ff98f26af382a16fb894f4861cb9a94077a0113;p=thirdparty%2Fkernel%2Fstable-queue.git

4.9-stable patches

added patches:
	random-set-up-the-numa-crng-instances-after-the-crng-is-fully-initialized.patch
---

diff --git a/queue-4.9/random-set-up-the-numa-crng-instances-after-the-crng-is-fully-initialized.patch b/queue-4.9/random-set-up-the-numa-crng-instances-after-the-crng-is-fully-initialized.patch
new file mode 100644
index 00000000000..1b4bcfdadb8
--- /dev/null
+++ b/queue-4.9/random-set-up-the-numa-crng-instances-after-the-crng-is-fully-initialized.patch
@@ -0,0 +1,99 @@
+From 8ef35c866f8862df074a49a93b0309725812dea8 Mon Sep 17 00:00:00 2001
+From: Theodore Ts'o <tytso@mit.edu>
+Date: Wed, 11 Apr 2018 15:23:56 -0400
+Subject: random: set up the NUMA crng instances after the CRNG is fully initialized
+
+From: Theodore Ts'o <tytso@mit.edu>
+
+commit 8ef35c866f8862df074a49a93b0309725812dea8 upstream.
+
+Until the primary_crng is fully initialized, don't initialize the NUMA
+crng nodes.  Otherwise users of /dev/urandom on NUMA systems before
+the CRNG is fully initialized can get very bad quality randomness.  Of
+course everyone should move to getrandom(2) where this won't be an
+issue, but there's a lot of legacy code out there.  This related to
+CVE-2018-1108.
+
+Reported-by: Jann Horn <jannh@google.com>
+Fixes: 1e7f583af67b ("random: make /dev/urandom scalable for silly...")
+Cc: stable@kernel.org # 4.8+
+Signed-off-by: Theodore Ts'o <tytso@mit.edu>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/char/random.c |   46 +++++++++++++++++++++++++++-------------------
+ 1 file changed, 27 insertions(+), 19 deletions(-)
+
+--- a/drivers/char/random.c
++++ b/drivers/char/random.c
+@@ -819,6 +819,32 @@ static int crng_fast_load(const char *cp
+ 	return 1;
+ }
+ 
++#ifdef CONFIG_NUMA
++static void numa_crng_init(void)
++{
++	int i;
++	struct crng_state *crng;
++	struct crng_state **pool;
++
++	pool = kcalloc(nr_node_ids, sizeof(*pool), GFP_KERNEL|__GFP_NOFAIL);
++	for_each_online_node(i) {
++		crng = kmalloc_node(sizeof(struct crng_state),
++				    GFP_KERNEL | __GFP_NOFAIL, i);
++		spin_lock_init(&crng->lock);
++		crng_initialize(crng);
++		pool[i] = crng;
++	}
++	mb();
++	if (cmpxchg(&crng_node_pool, NULL, pool)) {
++		for_each_node(i)
++			kfree(pool[i]);
++		kfree(pool);
++	}
++}
++#else
++static void numa_crng_init(void) {}
++#endif
++
+ static void crng_reseed(struct crng_state *crng, struct entropy_store *r)
+ {
+ 	unsigned long	flags;
+@@ -848,6 +874,7 @@ static void crng_reseed(struct crng_stat
+ 	memzero_explicit(&buf, sizeof(buf));
+ 	crng->init_time = jiffies;
+ 	if (crng == &primary_crng && crng_init < 2) {
++		numa_crng_init();
+ 		crng_init = 2;
+ 		process_random_ready_list();
+ 		wake_up_interruptible(&crng_init_wait);
+@@ -1661,29 +1688,10 @@ static void init_std_data(struct entropy
+  */
+ static int rand_initialize(void)
+ {
+-#ifdef CONFIG_NUMA
+-	int i;
+-	struct crng_state *crng;
+-	struct crng_state **pool;
+-#endif
+-
+ 	init_std_data(&input_pool);
+ 	init_std_data(&blocking_pool);
+ 	crng_initialize(&primary_crng);
+ 	crng_global_init_time = jiffies;
+-
+-#ifdef CONFIG_NUMA
+-	pool = kcalloc(nr_node_ids, sizeof(*pool), GFP_KERNEL|__GFP_NOFAIL);
+-	for_each_online_node(i) {
+-		crng = kmalloc_node(sizeof(struct crng_state),
+-				    GFP_KERNEL | __GFP_NOFAIL, i);
+-		spin_lock_init(&crng->lock);
+-		crng_initialize(crng);
+-		pool[i] = crng;
+-	}
+-	mb();
+-	crng_node_pool = pool;
+-#endif
+ 	return 0;
+ }
+ early_initcall(rand_initialize);
diff --git a/queue-4.9/series b/queue-4.9/series
index d513c14b1c0..e220dacddc5 100644
--- a/queue-4.9/series
+++ b/queue-4.9/series
@@ -2,3 +2,4 @@ ext4-prevent-right-shifting-extents-beyond-ext_max_blocks.patch
 ext4-set-h_journal-if-there-is-a-failure-starting-a-reserved-handle.patch
 ext4-add-validity-checks-for-bitmap-block-numbers.patch
 ext4-fix-bitmap-position-validation.patch
+random-set-up-the-numa-crng-instances-after-the-crng-is-fully-initialized.patch