apparmor: audit policy ns specified in policy load

Verify that profiles in a load set specify the same policy ns and
audit the name of the policy ns that policy is being loaded for.
Signed-off-by: John Johansen <john.johansen@canonical.com>

security/apparmor/include/policy_unpack.h

@@ -23,6 +23,7 @@ struct aa_load_ent {
 	struct aa_profile *new;
 	struct aa_profile *old;
 	struct aa_profile *rename;
+	const char *ns_name;
 };
 
 void aa_load_ent_free(struct aa_load_ent *ent);

security/apparmor/policy.c

@@ -819,7 +819,7 @@ ssize_t aa_replace_profiles(struct aa_ns *view, bool noreplace,
 	struct aa_ns *ns = NULL;
 	struct aa_load_ent *ent, *tmp;
 	int op = OP_PROF_REPL;
-	ssize_t error;
+	ssize_t count, error;
 	LIST_HEAD(lh);
 
 	/* released below */
@@ -827,14 +827,40 @@ ssize_t aa_replace_profiles(struct aa_ns *view, bool noreplace,
 	if (error)
 		goto out;
 
-	/* released below */
+	/* ensure that profiles are all for the same ns
+	 * TODO: update locking to remove this constaint. All profiles in
+	 *       the load set must succeed as a set or the load will
+	 *       fail. Sort ent list and take ns locks in hierarchy order
+	 */
+	count = 0;
+	list_for_each_entry(ent, &lh, list) {
+		if (ns_name) {
+			if (ent->ns_name &&
+			    strcmp(ent->ns_name, ns_name) != 0) {
+				info = "policy load has mixed namespaces";
+				error = -EACCES;
+				goto fail;
+			}
+		} else if (ent->ns_name) {
+			if (count) {
+				info = "policy load has mixed namespaces";
+				error = -EACCES;
+				goto fail;
+			}
+			ns_name = ent->ns_name;
+		} else
+			count++;
+	}
+	if (ns_name) {
 		ns = aa_prepare_ns(view, ns_name);
-	if (!ns) {
-		error = audit_policy(__aa_current_profile(), op, GFP_KERNEL,
-				     NULL, ns_name,
-				     "failed to prepare namespace", -ENOMEM);
-		goto free;
+		if (IS_ERR(ns)) {
+			info = "failed to prepare namespace";
+			error = PTR_ERR(ns);
+			ns = NULL;
+			goto fail;
 		}
+	} else
+		ns = aa_get_ns(view);
 
 	mutex_lock(&ns->lock);
 	/* setup parent and ns info */
@@ -964,7 +990,8 @@ ssize_t aa_replace_profiles(struct aa_ns *view, bool noreplace,
 
 	/* audit cause of failure */
 	op = (!ent->old) ? OP_PROF_LOAD : OP_PROF_REPL;
-	audit_policy(__aa_current_profile(), op, GFP_KERNEL, NULL,
+fail:
+	audit_policy(__aa_current_profile(), op, GFP_KERNEL, ns_name,
 		     ent->new->base.hname, info, error);
 	/* audit status that rest of profiles in the atomic set failed too */
 	info = "valid profile in failed atomic policy load";
@@ -975,10 +1002,9 @@ ssize_t aa_replace_profiles(struct aa_ns *view, bool noreplace,
 			continue;
 		}
 		op = (!ent->old) ? OP_PROF_LOAD : OP_PROF_REPL;
-		audit_policy(__aa_current_profile(), op, GFP_KERNEL, NULL,
+		audit_policy(__aa_current_profile(), op, GFP_KERNEL, ns_name,
 			     tmp->new->base.hname, info, error);
 	}
-free:
 	list_for_each_entry_safe(ent, tmp, &lh, list) {
 		list_del_init(&ent->list);
 		aa_load_ent_free(ent);
@@ -1005,6 +1031,7 @@ ssize_t aa_remove_profiles(struct aa_ns *view, char *fqname, size_t size)
 	struct aa_ns *root = NULL, *ns = NULL;
 	struct aa_profile *profile = NULL;
 	const char *name = fqname, *info = NULL;
+	char *ns_name = NULL;
 	ssize_t error = 0;
 
 	if (*fqname == 0) {
@@ -1016,7 +1043,6 @@ ssize_t aa_remove_profiles(struct aa_ns *view, char *fqname, size_t size)
 	root = view;
 
 	if (fqname[0] == ':') {
-		char *ns_name;
 		name = aa_split_fqname(fqname, &ns_name);
 		/* released below */
 		ns = aa_find_ns(root, ns_name);
@@ -1050,7 +1076,7 @@ ssize_t aa_remove_profiles(struct aa_ns *view, char *fqname, size_t size)
 
 	/* don't fail removal if audit fails */
 	(void) audit_policy(__aa_current_profile(), OP_PROF_RM, GFP_KERNEL,
-			    NULL, name, info, error);
+			    ns_name, name, info, error);
 	aa_put_ns(ns);
 	aa_put_profile(profile);
 	return size;
@@ -1061,6 +1087,6 @@ ssize_t aa_remove_profiles(struct aa_ns *view, char *fqname, size_t size)
 
 fail:
 	(void) audit_policy(__aa_current_profile(), OP_PROF_RM, GFP_KERNEL,
-			    NULL, name, info, error);
+			    ns_name, name, info, error);
 	return error;
 }

security/apparmor/policy_unpack.c

@@ -91,6 +91,7 @@ static void audit_cb(struct audit_buffer *ab, void *va)
 /**
  * audit_iface - do audit message for policy unpacking/load/replace/remove
  * @new: profile if it has been allocated (MAYBE NULL)
+ * @ns_name: name of the ns the profile is to be loaded to (MAY BE NULL)
  * @name: name of the profile being manipulated (MAYBE NULL)
  * @info: any extra info about the failure (MAYBE NULL)
  * @e: buffer position info
@@ -98,14 +99,16 @@ static void audit_cb(struct audit_buffer *ab, void *va)
  *
  * Returns: %0 or error
  */
-static int audit_iface(struct aa_profile *new, const char *name,
-		       const char *info, struct aa_ext *e, int error)
+static int audit_iface(struct aa_profile *new, const char *ns_name,
+		       const char *name, const char *info, struct aa_ext *e,
+		       int error)
 {
 	struct aa_profile *profile = __aa_current_profile();
 	struct common_audit_data sa;
 	struct apparmor_audit_data aad = {0,};
 	sa.type = LSM_AUDIT_DATA_NONE;
 	sa.aad = &aad;
+	aad.iface.ns = ns_name;
 	if (e)
 		aad.iface.pos = e->pos - e->start;
 	aad.iface.target = new;
@@ -486,19 +489,32 @@ static bool unpack_rlimits(struct aa_ext *e, struct aa_profile *profile)
  *
  * NOTE: unpack profile sets audit struct if there is a failure
  */
-static struct aa_profile *unpack_profile(struct aa_ext *e)
+static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
 {
 	struct aa_profile *profile = NULL;
-	const char *name = NULL;
+	const char *tmpname, *tmpns = NULL, *name = NULL;
+	size_t ns_len;
 	int i, error = -EPROTO;
 	kernel_cap_t tmpcap;
 	u32 tmp;
 
+	*ns_name = NULL;
+
 	/* check that we have the right struct being passed */
 	if (!unpack_nameX(e, AA_STRUCT, "profile"))
 		goto fail;
 	if (!unpack_str(e, &name, NULL))
 		goto fail;
+	if (*name == '\0')
+		goto fail;
+
+	tmpname = aa_splitn_fqname(name, strlen(name), &tmpns, &ns_len);
+	if (tmpns) {
+		*ns_name = kstrndup(tmpns, ns_len, GFP_KERNEL);
+		if (!*ns_name)
+			goto fail;
+		name = tmpname;
+	}
 
 	profile = aa_alloc_profile(name, GFP_KERNEL);
 	if (!profile)
@@ -646,7 +662,8 @@ static struct aa_profile *unpack_profile(struct aa_ext *e)
 		name = NULL;
 	else if (!name)
 		name = "unknown";
-	audit_iface(profile, name, "failed to unpack profile", e, error);
+	audit_iface(profile, NULL, name, "failed to unpack profile", e,
+		    error);
 	aa_free_profile(profile);
 
 	return ERR_PTR(error);
@@ -669,7 +686,7 @@ static int verify_header(struct aa_ext *e, int required, const char **ns)
 	/* get the interface version */
 	if (!unpack_u32(e, &e->version, "version")) {
 		if (required) {
-			audit_iface(NULL, NULL, "invalid profile format",
+			audit_iface(NULL, NULL, NULL, "invalid profile format",
 				    e, error);
 			return error;
 		}
@@ -680,15 +697,21 @@ static int verify_header(struct aa_ext *e, int required, const char **ns)
 	 * Mask off everything that is not kernel abi version
 	 */
 	if (VERSION_LT(e->version, v5) && VERSION_GT(e->version, v7)) {
-		audit_iface(NULL, NULL, "unsupported interface version",
+		audit_iface(NULL, NULL, NULL, "unsupported interface version",
 			    e, error);
 		return error;
 	}
 
 	/* read the namespace if present */
 	if (unpack_str(e, &name, "namespace")) {
+		if (*name == '\0') {
+			audit_iface(NULL, NULL, NULL, "invalid namespace name",
+				    e, error);
+			return error;
+		}
 		if (*ns && strcmp(*ns, name))
-			audit_iface(NULL, NULL, "invalid ns change", e, error);
+			audit_iface(NULL, NULL, NULL, "invalid ns change", e,
+				    error);
 		else if (!*ns)
 			*ns = name;
 	}
@@ -730,7 +753,7 @@ static int verify_profile(struct aa_profile *profile)
 	if (profile->file.dfa &&
 	    !verify_dfa_xindex(profile->file.dfa,
 			       profile->file.trans.size)) {
-		audit_iface(profile, NULL, "Invalid named transition",
+		audit_iface(profile, NULL, NULL, "Invalid named transition",
 			    NULL, -EPROTO);
 		return -EPROTO;
 	}
@@ -744,6 +767,7 @@ void aa_load_ent_free(struct aa_load_ent *ent)
 		aa_put_profile(ent->rename);
 		aa_put_profile(ent->old);
 		aa_put_profile(ent->new);
+		kfree(ent->ns_name);
 		kzfree(ent);
 	}
 }
@@ -782,13 +806,14 @@ int aa_unpack(struct aa_loaddata *udata, struct list_head *lh,
 
 	*ns = NULL;
 	while (e.pos < e.end) {
+		char *ns_name = NULL;
 		void *start;
 		error = verify_header(&e, e.pos == e.start, ns);
 		if (error)
 			goto fail;
 
 		start = e.pos;
-		profile = unpack_profile(&e);
+		profile = unpack_profile(&e, &ns_name);
 		if (IS_ERR(profile)) {
 			error = PTR_ERR(profile);
 			goto fail;
@@ -810,6 +835,7 @@ int aa_unpack(struct aa_loaddata *udata, struct list_head *lh,
 		}
 
 		ent->new = profile;
+		ent->ns_name = ns_name;
 		list_add_tail(&ent->list, lh);
 	}
 	udata->abi = e.version & K_ABI_MASK;