Patch "libceph: rename and align ceph_x_authorizer::reply_buf" has been added to the 4.9-stable tree

This is a note to let you know that I've just added the patch titled

libceph: rename and align ceph_x_authorizer::reply_buf

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
libceph-rename-and-align-ceph_x_authorizer-reply_buf.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Ilya Dryomov <[email protected]>
Date: Fri, 2 Dec 2016 16:35:07 +0100
Subject: libceph: rename and align ceph_x_authorizer::reply_buf

From: Ilya Dryomov <[email protected]>

commit 7882a26d2e2e520099e2961d5e2e870f8e4172dc upstream.

It's going to be used as a temporary buffer for in-place en/decryption with ceph_crypt() instead of on-stack buffers, so rename to enc_buf. Ensure alignment to avoid GFP_ATOMIC allocations in the crypto stack.

---
 net/ceph/auth_x.c |   10 +++++-----
 net/ceph/auth_x.h |    3 ++-
 2 files changed, 7 insertions(+), 6 deletions(-)

@@ -603,8 +603,8 @@ static int ceph_x_create_authorizer(
 	auth->authorizer = (struct ceph_authorizer *) au;
 	auth->authorizer_buf = au->buf->vec.iov_base;
 	auth->authorizer_buf_len = au->buf->vec.iov_len;
-	auth->authorizer_reply_buf = au->reply_buf;
-	auth->authorizer_reply_buf_len = sizeof (au->reply_buf);
+	auth->authorizer_reply_buf = au->enc_buf;
+	auth->authorizer_reply_buf_len = CEPHX_AU_ENC_BUF_LEN;
 	auth->sign_message = ac->ops->sign_message;
 	auth->check_message_signature = ac->ops->check_message_signature;
 

@@ -638,10 +638,10 @@ static int ceph_x_verify_authorizer_repl
 	int ret = 0;
 	struct ceph_x_authorize_reply reply;
 	void *preply = &reply;
-	void *p = au->reply_buf;
-	void *end = p + sizeof(au->reply_buf);
+	void *p = au->enc_buf;
 
-	ret = ceph_x_decrypt(&au->session_key, &p, end, &preply, sizeof(reply));
+	ret = ceph_x_decrypt(&au->session_key, &p, p + CEPHX_AU_ENC_BUF_LEN,
+			     &preply, sizeof(reply));
 	if (ret < 0)
 		return ret;
 	if (ret != sizeof(reply))

@@ -24,6 +24,7 @@ struct ceph_x_ticket_handler {
 	unsigned long renew_after, expires;
 };
 
+#define CEPHX_AU_ENC_BUF_LEN	128  /* big enough for encrypted blob */
 
 struct ceph_x_authorizer {
 	struct ceph_authorizer base;

@@ -32,7 +33,7 @@ struct ceph_x_authorizer {
 	unsigned int service;
 	u64 nonce;
 	u64 secret_id;
-	char reply_buf[128];  /* big enough for encrypted blob */
+	char enc_buf[CEPHX_AU_ENC_BUF_LEN] __aligned(8);
 };
 
 struct ceph_x_info {

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/libceph-switch-ceph_x_decrypt-to-ceph_crypt.patch queue-4.9/libceph-introduce-ceph_x_encrypt_offset.patch queue-4.9/libceph-rename-and-align-ceph_x_authorizer-reply_buf.patch queue-4.9/libceph-ceph_x_encrypt_buflen-takes-in_len.patch queue-4.9/libceph-introduce-ceph_crypt-for-in-place-en-decryption.patch queue-4.9/libceph-old_key-in-process_one_ticket-is-redundant.patch queue-4.9/libceph-tweak-calcu_signature-a-little.patch queue-4.9/libceph-remove-now-unused-ceph_-en-de-crypt-functions.patch queue-4.9/ceph-fix-bad-endianness-handling-in-parse_reply_info_extra.patch queue-4.9/libceph-switch-ceph_x_encrypt-to-ceph_crypt.patch