The cred_prepared bprm flag has a misleading name. It has nothing to do
with the bprm_prepare_cred hook, and actually tracks if bprm_set_creds has
been called. Rename this flag and improve its comment.

Cc: David Howells <dhowells@redhat.com>
Cc: John Johansen <john.johansen@canonical.com>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Stephen Smalley <redacted>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Cc: James Morris <redacted>
Signed-off-by: Kees Cook <redacted>
---
 fs/binfmt_flat.c           | 2 +-
 fs/exec.c                  | 2 +-
 include/linux/binfmts.h    | 8 ++++++--
 security/apparmor/domain.c | 2 +-
 security/selinux/hooks.c   | 2 +-
 security/smack/smack_lsm.c | 2 +-
 security/tomoyo/tomoyo.c   | 2 +-
 7 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
index 2edcefc0a294..a722530cc468 100644
--- a/fs/binfmt_flat.c
+++ b/fs/binfmt_flat.c

@@ -885,7 +885,7 @@ static int load_flat_shared_library(int id, struct lib_info *libs)
         * as we're past the point of no return and are dealing with shared
         * libraries.
         */
-       bprm.cred_prepared = 1;
+       bprm.called_set_creds = 1;