From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Date: Wed, 7 Jun 2017 22:44:54 -0400
Subject: ceph: ensure RNG is seeded before using
Git-commit: ae5b806a3d3c23d9d3b57aecbe687a0bd82ab086
Patch-mainline: v4.13-rc1
References: FATE#324714

Ceph uses the RNG for various nonce generations, and it shouldn't accept
using bad randomness. So, we wait for the RNG to be properly seeded. We
do this by calling wait_for_random_bytes() in a function that is
certainly called in process context, early on, so that all subsequent
calls to get_random_bytes are necessarily acceptable.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: "Yan, Zheng" <zyan@redhat.com>
Cc: Sage Weil <sage@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Acked-by: Luis Henriques <lhenriques@suse.com>
---
 net/ceph/ceph_common.c |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

--- a/net/ceph/ceph_common.c
+++ b/net/ceph/ceph_common.c
@@ -598,7 +598,11 @@ struct ceph_client *ceph_create_client(s
 {
 	struct ceph_client *client;
 	struct ceph_entity_addr *myaddr = NULL;
-	int err = -ENOMEM;
+	int err;
+
+	err = wait_for_random_bytes();
+	if (err < 0)
+		return ERR_PTR(err);
 
 	client = kzalloc(sizeof(*client), GFP_KERNEL);
 	if (client == NULL)