commit c27a3e4d upstream.

We hard code cephx auth ticket buffer size to 256 bytes.  This isn't
enough for any moderate setups and, in case tickets themselves are not
encrypted, leads to buffer overflows (ceph_x_decrypt() errors out, but
ceph_decode_copy() doesn't - it's just a memcpy() wrapper).  Since the
buffer is allocated dynamically anyway, allocated it a bit later, at
the point where we know how much is going to be needed.

Fixes: http://tracker.ceph.com/issues/8979Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Sage Weil <sage@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>