capabilities: introduce security_capable_noaudit

Exactly like security_capable except don't audit any denials.  This is for
places where the kernel may make decisions about what to do if a task has a
given capability, but which failing that capability is not a sign of a
security policy violation.  An example is checking if a task has
CAP_SYS_ADMIN to lower it's likelyhood of being killed by the oom killer.
This check is not a security violation if it is denied.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Serge E. Hallyn <serge.hallyn@canonical.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/security/security.c b/security/security.c
index b9e57f4fc44a..b7edaae77d1d 100644
--- a/security/security.c
+++ b/security/security.c
@@ -160,6 +160,12 @@ int security_capable(const struct cred *cred, struct user_namespace *ns,
 	return security_ops->capable(cred, ns, cap, SECURITY_CAP_AUDIT);
 }
 
+int security_capable_noaudit(const struct cred *cred, struct user_namespace *ns,
+			     int cap)
+{
+	return security_ops->capable(cred, ns, cap, SECURITY_CAP_NOAUDIT);
+}
+
 int security_real_capable(struct task_struct *tsk, struct user_namespace *ns,
 			  int cap)
 {