File-copy from v4.4.100
This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Please refer to that tree for all history prior to this point.
Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/security/apparmor/ipc.c b/security/apparmor/ipc.c
new file mode 100644
index 0000000..777ac1c
--- /dev/null
+++ b/security/apparmor/ipc.c
@@ -0,0 +1,111 @@
+/*
+ * AppArmor security module
+ *
+ * This file contains AppArmor ipc mediation
+ *
+ * Copyright (C) 1998-2008 Novell/SUSE
+ * Copyright 2009-2010 Canonical Ltd.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, version 2 of the
+ * License.
+ */
+
+#include <linux/gfp.h>
+#include <linux/ptrace.h>
+
+#include "include/audit.h"
+#include "include/capability.h"
+#include "include/context.h"
+#include "include/policy.h"
+#include "include/ipc.h"
+
+/* call back to audit ptrace fields */
+static void audit_cb(struct audit_buffer *ab, void *va)
+{
+ struct common_audit_data *sa = va;
+ audit_log_format(ab, " target=");
+ audit_log_untrustedstring(ab, sa->aad->target);
+}
+
+/**
+ * aa_audit_ptrace - do auditing for ptrace
+ * @profile: profile being enforced (NOT NULL)
+ * @target: profile being traced (NOT NULL)
+ * @error: error condition
+ *
+ * Returns: %0 or error code
+ */
+static int aa_audit_ptrace(struct aa_profile *profile,
+ struct aa_profile *target, int error)
+{
+ struct common_audit_data sa;
+ struct apparmor_audit_data aad = {0,};
+ sa.type = LSM_AUDIT_DATA_NONE;
+ sa.aad = &aad;
+ aad.op = OP_PTRACE;
+ aad.target = target;
+ aad.error = error;
+
+ return aa_audit(AUDIT_APPARMOR_AUTO, profile, GFP_ATOMIC, &sa,
+ audit_cb);
+}
+
+/**
+ * aa_may_ptrace - test if tracer task can trace the tracee
+ * @tracer: profile of the task doing the tracing (NOT NULL)
+ * @tracee: task to be traced
+ * @mode: whether PTRACE_MODE_READ || PTRACE_MODE_ATTACH
+ *
+ * Returns: %0 else error code if permission denied or error
+ */
+int aa_may_ptrace(struct aa_profile *tracer, struct aa_profile *tracee,
+ unsigned int mode)
+{
+ /* TODO: currently only based on capability, not extended ptrace
+ * rules,
+ * Test mode for PTRACE_MODE_READ || PTRACE_MODE_ATTACH
+ */
+
+ if (unconfined(tracer) || tracer == tracee)
+ return 0;
+ /* log this capability request */
+ return aa_capable(tracer, CAP_SYS_PTRACE, 1);
+}
+
+/**
+ * aa_ptrace - do ptrace permission check and auditing
+ * @tracer: task doing the tracing (NOT NULL)
+ * @tracee: task being traced (NOT NULL)
+ * @mode: ptrace mode either PTRACE_MODE_READ || PTRACE_MODE_ATTACH
+ *
+ * Returns: %0 else error code if permission denied or error
+ */
+int aa_ptrace(struct task_struct *tracer, struct task_struct *tracee,
+ unsigned int mode)
+{
+ /*
+ * tracer can ptrace tracee when
+ * - tracer is unconfined ||
+ * - tracer is in complain mode
+ * - tracer has rules allowing it to trace tracee currently this is:
+ * - confined by the same profile ||
+ * - tracer profile has CAP_SYS_PTRACE
+ */
+
+ struct aa_profile *tracer_p = aa_get_task_profile(tracer);
+ int error = 0;
+
+ if (!unconfined(tracer_p)) {
+ struct aa_profile *tracee_p = aa_get_task_profile(tracee);
+
+ error = aa_may_ptrace(tracer_p, tracee_p, mode);
+ error = aa_audit_ptrace(tracer_p, tracee_p, error);
+
+ aa_put_profile(tracee_p);
+ }
+ aa_put_profile(tracer_p);
+
+ return error;
+}