Commit f5f2c9a0 authored by Ilya Dryomov's avatar Ilya Dryomov
Browse files

libceph: align session_key and con_secret to 16 bytes 



crypto_shash_setkey() and crypto_aead_setkey() will do a (small)
GFP_ATOMIC allocation to align the key if it isn't suitably aligned.
It's not a big deal, but at the same time easy to avoid.

The actual alignment requirement is dynamic, queryable with
crypto_shash_alignmask() and crypto_aead_alignmask(), but shouldn't
be stricter than 16 bytes for our algorithms.

Fixes: cd1a677c ("libceph, ceph: implement msgr2.1 protocol (crc and secure modes)")
Signed-off-by: default avatarIlya Dryomov <idryomov@gmail.com>
parent ad32fe88

net/ceph/messenger_v2.c

+10 −2
Original line number Diff line number Diff line
@@ -2033,10 +2033,18 @@ static int process_auth_reply_more(struct ceph_connection *con, 
	return -EINVAL;

}



/*

 * Align session_key and con_secret to avoid GFP_ATOMIC allocation

 * inside crypto_shash_setkey() and crypto_aead_setkey() called from

 * setup_crypto().  __aligned(16) isn't guaranteed to work for stack

 * objects, so do it by hand.

 */

static int process_auth_done(struct ceph_connection *con, void *p, void *end)

{

	u8 session_key[CEPH_KEY_LEN];

	u8 con_secret[CEPH_MAX_CON_SECRET_LEN];

	u8 session_key_buf[CEPH_KEY_LEN + 16];

	u8 con_secret_buf[CEPH_MAX_CON_SECRET_LEN + 16];

	u8 *session_key = PTR_ALIGN(&session_key_buf[0], 16);

	u8 *con_secret = PTR_ALIGN(&con_secret_buf[0], 16);

	int session_key_len, con_secret_len;

	int payload_len;

	u64 global_id;