UBUNTU: SAUCE: apparmor4.0.0 [02/90]: LSM stacking v39: SM: Infrastructure management of the sock security

BugLink: http://bugs.launchpad.net/bugs/2028253

Move management of the sock->sk_security blob out
of the individual security modules and into the security
infrastructure. Instead of allocating the blobs from within
the modules the modules tell the infrastructure how much
space is required, and the space is allocated there.

Acked-by: Paul Moore <paul@paul-moore.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
(cherry picked from commit c493287fe3495fcf3854f246b42cbaa88ed130da
https://git.launchpad.net/~apparmor-dev/ubuntu-kernel-next)
Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>

security/apparmor/include/net.h

@@ -51,10 +51,9 @@ struct aa_sk_ctx {
 	struct aa_label *peer;
 };
 
-#define SK_CTX(X) ((X)->sk_security)
 static inline struct aa_sk_ctx *aa_sock(const struct sock *sk)
 {
-	return sk->sk_security;
+	return sk->sk_security + apparmor_blob_sizes.lbs_sock;
 }
 
 #define DEFINE_AUDIT_NET(NAME, OP, SK, F, T, P)				  \