Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 187 insertions, 0 deletions

diff --git a/security/apparmor/resource.c b/security/apparmor/resource.c
new file mode 100644
index 000000000..1ae487425
--- /dev/null
+++ b/security/apparmor/resource.c
@@ -0,0 +1,187 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * AppArmor security module
+ *
+ * This file contains AppArmor resource mediation and attachment
+ *
+ * Copyright (C) 1998-2008 Novell/SUSE
+ * Copyright 2009-2010 Canonical Ltd.
+ */
+
+#include <linux/audit.h>
+#include <linux/security.h>
+
+#include "include/audit.h"
+#include "include/cred.h"
+#include "include/resource.h"
+#include "include/policy.h"
+
+/*
+ * Table of rlimit names: we generate it from resource.h.
+ */
+#include "rlim_names.h"
+
+struct aa_sfs_entry aa_sfs_entry_rlimit[] = {
+	AA_SFS_FILE_STRING("mask", AA_SFS_RLIMIT_MASK),
+	{ }
+};
+
+/* audit callback for resource specific fields */
+static void audit_cb(struct audit_buffer *ab, void *va)
+{
+	struct common_audit_data *sa = va;
+
+	audit_log_format(ab, " rlimit=%s value=%lu",
+			 rlim_names[aad(sa)->rlim.rlim], aad(sa)->rlim.max);
+	if (aad(sa)->peer) {
+		audit_log_format(ab, " peer=");
+		aa_label_xaudit(ab, labels_ns(aad(sa)->label), aad(sa)->peer,
+				FLAGS_NONE, GFP_ATOMIC);
+	}
+}
+
+/**
+ * audit_resource - audit setting resource limit
+ * @profile: profile being enforced  (NOT NULL)
+ * @resource: rlimit being auditing
+ * @value: value being set
+ * @error: error value
+ *
+ * Returns: 0 or sa->error else other error code on failure
+ */
+static int audit_resource(struct aa_profile *profile, unsigned int resource,
+			  unsigned long value, struct aa_label *peer,
+			  const char *info, int error)
+{
+	DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, OP_SETRLIMIT);
+
+	aad(&sa)->rlim.rlim = resource;
+	aad(&sa)->rlim.max = value;
+	aad(&sa)->peer = peer;
+	aad(&sa)->info = info;
+	aad(&sa)->error = error;
+
+	return aa_audit(AUDIT_APPARMOR_AUTO, profile, &sa, audit_cb);
+}
+
+/**
+ * aa_map_resouce - map compiled policy resource to internal #
+ * @resource: flattened policy resource number
+ *
+ * Returns: resource # for the current architecture.
+ *
+ * rlimit resource can vary based on architecture, map the compiled policy
+ * resource # to the internal representation for the architecture.
+ */
+int aa_map_resource(int resource)
+{
+	return rlim_map[resource];
+}
+
+static int profile_setrlimit(struct aa_profile *profile, unsigned int resource,
+			     struct rlimit *new_rlim)
+{
+	int e = 0;
+
+	if (profile->rlimits.mask & (1 << resource) && new_rlim->rlim_max >
+	    profile->rlimits.limits[resource].rlim_max)
+		e = -EACCES;
+	return audit_resource(profile, resource, new_rlim->rlim_max, NULL, NULL,
+			      e);
+}
+
+/**
+ * aa_task_setrlimit - test permission to set an rlimit
+ * @label - label confining the task  (NOT NULL)
+ * @task - task the resource is being set on
+ * @resource - the resource being set
+ * @new_rlim - the new resource limit  (NOT NULL)
+ *
+ * Control raising the processes hard limit.
+ *
+ * Returns: 0 or error code if setting resource failed
+ */
+int aa_task_setrlimit(struct aa_label *label, struct task_struct *task,
+		      unsigned int resource, struct rlimit *new_rlim)
+{
+	struct aa_profile *profile;
+	struct aa_label *peer;
+	int error = 0;
+
+	rcu_read_lock();
+	peer = aa_get_newest_cred_label(__task_cred(task));
+	rcu_read_unlock();
+
+	/* TODO: extend resource control to handle other (non current)
+	 * profiles.  AppArmor rules currently have the implicit assumption
+	 * that the task is setting the resource of a task confined with
+	 * the same profile or that the task setting the resource of another
+	 * task has CAP_SYS_RESOURCE.
+	 */
+
+	if (label != peer &&
+	    aa_capable(label, CAP_SYS_RESOURCE, CAP_OPT_NOAUDIT) != 0)
+		error = fn_for_each(label, profile,
+				audit_resource(profile, resource,
+					       new_rlim->rlim_max, peer,
+					       "cap_sys_resource", -EACCES));
+	else
+		error = fn_for_each_confined(label, profile,
+				profile_setrlimit(profile, resource, new_rlim));
+	aa_put_label(peer);
+
+	return error;
+}
+
+/**
+ * __aa_transition_rlimits - apply new profile rlimits
+ * @old_l: old label on task  (NOT NULL)
+ * @new_l: new label with rlimits to apply  (NOT NULL)
+ */
+void __aa_transition_rlimits(struct aa_label *old_l, struct aa_label *new_l)
+{
+	unsigned int mask = 0;
+	struct rlimit *rlim, *initrlim;
+	struct aa_profile *old, *new;
+	struct label_it i;
+
+	old = labels_profile(old_l);
+	new = labels_profile(new_l);
+
+	/* for any rlimits the profile controlled, reset the soft limit
+	 * to the lesser of the tasks hard limit and the init tasks soft limit
+	 */
+	label_for_each_confined(i, old_l, old) {
+		if (old->rlimits.mask) {
+			int j;
+
+			for (j = 0, mask = 1; j < RLIM_NLIMITS; j++,
+				     mask <<= 1) {
+				if (old->rlimits.mask & mask) {
+					rlim = current->signal->rlim + j;
+					initrlim = init_task.signal->rlim + j;
+					rlim->rlim_cur = min(rlim->rlim_max,
+							    initrlim->rlim_cur);
+				}
+			}
+		}
+	}
+
+	/* set any new hard limits as dictated by the new profile */
+	label_for_each_confined(i, new_l, new) {
+		int j;
+
+		if (!new->rlimits.mask)
+			continue;
+		for (j = 0, mask = 1; j < RLIM_NLIMITS; j++, mask <<= 1) {
+			if (!(new->rlimits.mask & mask))
+				continue;
+
+			rlim = current->signal->rlim + j;
+			rlim->rlim_max = min(rlim->rlim_max,
+					     new->rlimits.limits[j].rlim_max);
+			/* soft limit should not exceed hard limit */
+			rlim->rlim_cur = min(rlim->rlim_cur, rlim->rlim_max);
+		}
+	}
+}