--- /dev/null	Fri Dec 21 15:00:04 2018
+++ new/usr/src/tools/smatch/src/check_frees_param_strict.c	Fri Dec 21 15:00:04 2018
@@ -0,0 +1,162 @@
+/*
+ * Copyright (C) 2014 Oracle.
+ *
+ * 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; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see http://www.gnu.org/copyleft/gpl.txt
+ */
+
+/*
+ * This file is sort of like check_dereferences_param.c.  In theory the one
+ * difference should be that the param is NULL it should still be counted as a
+ * free.  But for now I don't handle that case.
+ */
+
+#include "smatch.h"
+#include "smatch_extra.h"
+#include "smatch_slist.h"
+
+static int my_id;
+
+STATE(freed);
+STATE(ignore);
+
+static struct smatch_state *unmatched_state(struct sm_state *sm)
+{
+	if (sm->state != &freed)
+		return &undefined;
+	if (parent_is_null_var_sym(sm->name, sm->sym))
+		return &freed;
+	return &undefined;
+}
+
+static void set_ignore(struct sm_state *sm, struct expression *mod_expr)
+{
+	set_state(my_id, sm->name, sm->sym, &ignore);
+}
+
+static int counter_was_inced(struct expression *expr)
+{
+	char *name;
+	struct symbol *sym;
+	char buf[256];
+	int ret = 0;
+
+	name = expr_to_var_sym(expr, &sym);
+	if (!name || !sym)
+		goto free;
+
+	snprintf(buf, sizeof(buf), "%s->users.counter", name);
+	ret = was_inced(buf, sym);
+free:
+	free_string(name);
+	return ret;
+}
+
+static void match_free(const char *fn, struct expression *expr, void *param)
+{
+	struct expression *arg, *tmp;
+	int cnt = 0;
+
+	arg = get_argument_from_call_expr(expr->args, PTR_INT(param));
+	if (!arg)
+		return;
+	while ((tmp = get_assigned_expr(arg))) {
+		arg = strip_expr(tmp);
+		if (cnt++ > 5)
+			break;
+	}
+
+	if (get_param_num(arg) < 0)
+		return;
+	if (param_was_set(arg))
+		return;
+	if (strcmp(fn, "kfree_skb") == 0 && counter_was_inced(arg))
+		return;
+
+	set_state_expr(my_id, arg, &freed);
+}
+
+static void set_param_freed(struct expression *expr, int param, char *key, char *value)
+{
+	struct expression *arg;
+	char *name;
+	struct symbol *sym;
+
+	while (expr->type == EXPR_ASSIGNMENT)
+		expr = strip_expr(expr->right);
+	if (expr->type != EXPR_CALL)
+		return;
+
+	arg = get_argument_from_call_expr(expr->args, param);
+	if (!arg)
+		return;
+	name = get_variable_from_key(arg, key, &sym);
+	if (!name || !sym)
+		goto free;
+	if (get_param_num_from_sym(sym) < 0)
+		goto free;
+
+	if (param_was_set_var_sym(name, sym))
+		goto free;
+
+	set_state(my_id, name, sym, &freed);
+free:
+	free_string(name);
+}
+
+static void param_freed_info(int return_id, char *return_ranges, struct expression *expr)
+{
+	struct sm_state *sm;
+	int param;
+	const char *param_name;
+
+	if (on_atomic_dec_path())
+		return;
+
+	FOR_EACH_MY_SM(my_id, __get_cur_stree(), sm) {
+		if (sm->state != &freed)
+			continue;
+
+		param = get_param_num_from_sym(sm->sym);
+		if (param < 0)
+			continue;
+
+		param_name = get_param_name(sm);
+		if (!param_name)
+			continue;
+
+		sql_insert_return_states(return_id, return_ranges, PARAM_FREED,
+					 param, param_name, "");
+	} END_FOR_EACH_SM(sm);
+}
+
+void check_frees_param_strict(int id)
+{
+	my_id = id;
+
+	if (option_project != PROJ_KERNEL)
+		return;
+
+	add_function_hook("kfree", &match_free, INT_PTR(0));
+	add_function_hook("kmem_cache_free", &match_free, INT_PTR(1));
+	add_function_hook("kfree_skb", &match_free, INT_PTR(0));
+	add_function_hook("kfree_skbmem", &match_free, INT_PTR(0));
+	add_function_hook("dma_pool_free", &match_free, INT_PTR(1));
+	add_function_hook("spi_unregister_controller", &match_free, INT_PTR(0));
+
+	select_return_states_hook(PARAM_FREED, &set_param_freed);
+	add_modification_hook(my_id, &set_ignore);
+	add_split_return_callback(&param_freed_info);
+
+	add_unmatched_state_hook(my_id, &unmatched_state);
+}
