11f5207b7SJohn Levon /*
21f5207b7SJohn Levon  * Copyright (C) 2010 Dan Carpenter.
31f5207b7SJohn Levon  *
41f5207b7SJohn Levon  * This program is free software; you can redistribute it and/or
51f5207b7SJohn Levon  * modify it under the terms of the GNU General Public License
61f5207b7SJohn Levon  * as published by the Free Software Foundation; either version 2
71f5207b7SJohn Levon  * of the License, or (at your option) any later version.
81f5207b7SJohn Levon  *
91f5207b7SJohn Levon  * This program is distributed in the hope that it will be useful,
101f5207b7SJohn Levon  * but WITHOUT ANY WARRANTY; without even the implied warranty of
111f5207b7SJohn Levon  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
121f5207b7SJohn Levon  * GNU General Public License for more details.
131f5207b7SJohn Levon  *
141f5207b7SJohn Levon  * You should have received a copy of the GNU General Public License
151f5207b7SJohn Levon  * along with this program; if not, see http://www.gnu.org/copyleft/gpl.txt
161f5207b7SJohn Levon  */
171f5207b7SJohn Levon 
181f5207b7SJohn Levon /*
191f5207b7SJohn Levon  * This is kernel specific stuff for smatch_extra.
201f5207b7SJohn Levon  */
211f5207b7SJohn Levon 
221f5207b7SJohn Levon #include "scope.h"
231f5207b7SJohn Levon #include "smatch.h"
241f5207b7SJohn Levon #include "smatch_extra.h"
251f5207b7SJohn Levon 
26*efe51d0cSJohn Levon static sval_t err_ptr_min;
27*efe51d0cSJohn Levon static sval_t err_ptr_max;
28*efe51d0cSJohn Levon static sval_t null_ptr;
29*efe51d0cSJohn Levon 
301f5207b7SJohn Levon static int implied_err_cast_return(struct expression *call, void *unused, struct range_list **rl)
311f5207b7SJohn Levon {
321f5207b7SJohn Levon 	struct expression *arg;
331f5207b7SJohn Levon 
341f5207b7SJohn Levon 	arg = get_argument_from_call_expr(call->args, 0);
35*efe51d0cSJohn Levon 	if (!get_implied_rl(arg, rl)) {
36*efe51d0cSJohn Levon 		*rl = alloc_rl(err_ptr_min, err_ptr_max);
37*efe51d0cSJohn Levon 		*rl = cast_rl(get_type(arg), *rl);
38*efe51d0cSJohn Levon 	}
391f5207b7SJohn Levon 	return 1;
401f5207b7SJohn Levon }
411f5207b7SJohn Levon 
421f5207b7SJohn Levon static void hack_ERR_PTR(struct symbol *sym)
431f5207b7SJohn Levon {
441f5207b7SJohn Levon 	struct symbol *arg;
451f5207b7SJohn Levon 	struct smatch_state *estate;
461f5207b7SJohn Levon 	struct range_list *after;
471f5207b7SJohn Levon 	sval_t low_error;
481f5207b7SJohn Levon 	sval_t minus_one;
491f5207b7SJohn Levon 	sval_t zero;
501f5207b7SJohn Levon 
511f5207b7SJohn Levon 	low_error.type = &long_ctype;
521f5207b7SJohn Levon 	low_error.value = -4095;
531f5207b7SJohn Levon 
541f5207b7SJohn Levon 	minus_one.type = &long_ctype;
551f5207b7SJohn Levon 	minus_one.value = -1;
561f5207b7SJohn Levon 
571f5207b7SJohn Levon 	zero.type = &long_ctype;
581f5207b7SJohn Levon 	zero.value = 0;
591f5207b7SJohn Levon 
601f5207b7SJohn Levon 	if (!sym || !sym->ident)
611f5207b7SJohn Levon 		return;
621f5207b7SJohn Levon 	if (strcmp(sym->ident->name, "ERR_PTR") != 0)
631f5207b7SJohn Levon 		return;
641f5207b7SJohn Levon 
651f5207b7SJohn Levon 	arg = first_ptr_list((struct ptr_list *)sym->ctype.base_type->arguments);
661f5207b7SJohn Levon 	if (!arg || !arg->ident)
671f5207b7SJohn Levon 		return;
681f5207b7SJohn Levon 
691f5207b7SJohn Levon 	estate = get_state(SMATCH_EXTRA, arg->ident->name, arg);
701f5207b7SJohn Levon 	if (!estate) {
711f5207b7SJohn Levon 		after = alloc_rl(low_error, minus_one);
721f5207b7SJohn Levon 	} else {
731f5207b7SJohn Levon 		after = rl_intersection(estate_rl(estate), alloc_rl(low_error, zero));
741f5207b7SJohn Levon 		if (rl_equiv(estate_rl(estate), after))
751f5207b7SJohn Levon 			return;
761f5207b7SJohn Levon 	}
771f5207b7SJohn Levon 	set_state(SMATCH_EXTRA, arg->ident->name, arg, alloc_estate_rl(after));
781f5207b7SJohn Levon }
791f5207b7SJohn Levon 
801f5207b7SJohn Levon static void match_param_valid_ptr(const char *fn, struct expression *call_expr,
811f5207b7SJohn Levon 			struct expression *assign_expr, void *_param)
821f5207b7SJohn Levon {
831f5207b7SJohn Levon 	int param = PTR_INT(_param);
841f5207b7SJohn Levon 	struct expression *arg;
851f5207b7SJohn Levon 	struct smatch_state *pre_state;
861f5207b7SJohn Levon 	struct smatch_state *end_state;
87*efe51d0cSJohn Levon 	struct range_list *rl;
881f5207b7SJohn Levon 
891f5207b7SJohn Levon 	arg = get_argument_from_call_expr(call_expr->args, param);
901f5207b7SJohn Levon 	pre_state = get_state_expr(SMATCH_EXTRA, arg);
91*efe51d0cSJohn Levon 	if (estate_rl(pre_state)) {
92*efe51d0cSJohn Levon 		rl = estate_rl(pre_state);
93*efe51d0cSJohn Levon 		rl = remove_range(rl, null_ptr, null_ptr);
94*efe51d0cSJohn Levon 		rl = remove_range(rl, err_ptr_min, err_ptr_max);
95*efe51d0cSJohn Levon 	} else {
96*efe51d0cSJohn Levon 		rl = alloc_rl(valid_ptr_min_sval, valid_ptr_max_sval);
97*efe51d0cSJohn Levon 	}
98*efe51d0cSJohn Levon 	end_state = alloc_estate_rl(rl);
991f5207b7SJohn Levon 	set_extra_expr_nomod(arg, end_state);
1001f5207b7SJohn Levon }
1011f5207b7SJohn Levon 
1021f5207b7SJohn Levon static void match_param_err_or_null(const char *fn, struct expression *call_expr,
1031f5207b7SJohn Levon 			struct expression *assign_expr, void *_param)
1041f5207b7SJohn Levon {
1051f5207b7SJohn Levon 	int param = PTR_INT(_param);
1061f5207b7SJohn Levon 	struct expression *arg;
1071f5207b7SJohn Levon 	struct range_list *rl;
1081f5207b7SJohn Levon 	struct smatch_state *pre_state;
1091f5207b7SJohn Levon 	struct smatch_state *end_state;
1101f5207b7SJohn Levon 
1111f5207b7SJohn Levon 	arg = get_argument_from_call_expr(call_expr->args, param);
1121f5207b7SJohn Levon 	pre_state = get_state_expr(SMATCH_EXTRA, arg);
113*efe51d0cSJohn Levon 	call_results_to_rl(call_expr, &ptr_ctype, "0,(-4095)-(-1)", &rl);
1141f5207b7SJohn Levon 	rl = rl_intersection(estate_rl(pre_state), rl);
115*efe51d0cSJohn Levon 	rl = cast_rl(get_type(arg), rl);
1161f5207b7SJohn Levon 	end_state = alloc_estate_rl(rl);
1171f5207b7SJohn Levon 	set_extra_expr_nomod(arg, end_state);
1181f5207b7SJohn Levon }
1191f5207b7SJohn Levon 
1201f5207b7SJohn Levon static void match_not_err(const char *fn, struct expression *call_expr,
1211f5207b7SJohn Levon 			struct expression *assign_expr, void *unused)
1221f5207b7SJohn Levon {
1231f5207b7SJohn Levon 	struct expression *arg;
1241f5207b7SJohn Levon 	struct smatch_state *pre_state;
125*efe51d0cSJohn Levon 	struct range_list *rl;
1261f5207b7SJohn Levon 
1271f5207b7SJohn Levon 	arg = get_argument_from_call_expr(call_expr->args, 0);
1281f5207b7SJohn Levon 	pre_state = get_state_expr(SMATCH_EXTRA, arg);
129*efe51d0cSJohn Levon 	if (estate_rl(pre_state)) {
130*efe51d0cSJohn Levon 		rl = estate_rl(pre_state);
131*efe51d0cSJohn Levon 		rl = remove_range(rl, err_ptr_min, err_ptr_max);
132*efe51d0cSJohn Levon 	} else {
133*efe51d0cSJohn Levon 		rl = alloc_rl(valid_ptr_min_sval, valid_ptr_max_sval);
134*efe51d0cSJohn Levon 	}
135*efe51d0cSJohn Levon 	rl = cast_rl(get_type(arg), rl);
136*efe51d0cSJohn Levon 	set_extra_expr_nomod(arg, alloc_estate_rl(rl));
1371f5207b7SJohn Levon }
1381f5207b7SJohn Levon 
1391f5207b7SJohn Levon static void match_err(const char *fn, struct expression *call_expr,
1401f5207b7SJohn Levon 			struct expression *assign_expr, void *unused)
1411f5207b7SJohn Levon {
1421f5207b7SJohn Levon 	struct expression *arg;
1431f5207b7SJohn Levon 	struct smatch_state *pre_state;
144*efe51d0cSJohn Levon 	struct range_list *rl;
1451f5207b7SJohn Levon 
1461f5207b7SJohn Levon 	arg = get_argument_from_call_expr(call_expr->args, 0);
1471f5207b7SJohn Levon 	pre_state = get_state_expr(SMATCH_EXTRA, arg);
148*efe51d0cSJohn Levon 	rl = estate_rl(pre_state);
149*efe51d0cSJohn Levon 	if (!rl)
150*efe51d0cSJohn Levon 		rl = alloc_rl(err_ptr_min, err_ptr_max);
151*efe51d0cSJohn Levon 	rl = rl_intersection(rl, alloc_rl(err_ptr_min, err_ptr_max));
152*efe51d0cSJohn Levon 	rl = cast_rl(get_type(arg), rl);
153*efe51d0cSJohn Levon 	set_extra_expr_nomod(arg, alloc_estate_rl(rl));
1541f5207b7SJohn Levon }
1551f5207b7SJohn Levon 
1561f5207b7SJohn Levon static void match_container_of_macro(const char *fn, struct expression *expr, void *unused)
1571f5207b7SJohn Levon {
1581f5207b7SJohn Levon 	set_extra_expr_mod(expr->left, alloc_estate_range(valid_ptr_min_sval, valid_ptr_max_sval));
1591f5207b7SJohn Levon }
1601f5207b7SJohn Levon 
1611f5207b7SJohn Levon static void match_container_of(struct expression *expr)
1621f5207b7SJohn Levon {
1631f5207b7SJohn Levon 	struct expression *right = expr->right;
1641f5207b7SJohn Levon 	char *macro;
1651f5207b7SJohn Levon 
1661f5207b7SJohn Levon 	/*
1671f5207b7SJohn Levon 	 * The problem here is that sometimes the container_of() macro is itself
1681f5207b7SJohn Levon 	 * inside a macro and get_macro() only returns the name of the outside
1691f5207b7SJohn Levon 	 * macro.
1701f5207b7SJohn Levon 	 */
1711f5207b7SJohn Levon 
1721f5207b7SJohn Levon 	/*
1731f5207b7SJohn Levon 	 * This actually an expression statement assignment but smatch_flow
1741f5207b7SJohn Levon 	 * pre-mangles it for us so we only get the last chunk:
1751f5207b7SJohn Levon 	 * sk = (typeof(sk))((char *)__mptr - offsetof(...))
1761f5207b7SJohn Levon 	 */
1771f5207b7SJohn Levon 
1781f5207b7SJohn Levon 	macro = get_macro_name(right->pos);
1791f5207b7SJohn Levon 	if (!macro)
1801f5207b7SJohn Levon 		return;
1811f5207b7SJohn Levon 	if (right->type != EXPR_CAST)
1821f5207b7SJohn Levon 		return;
1831f5207b7SJohn Levon 	right = strip_expr(right);
1841f5207b7SJohn Levon 	if (right->type != EXPR_BINOP || right->op != '-' ||
1851f5207b7SJohn Levon 	    right->left->type != EXPR_CAST)
1861f5207b7SJohn Levon 		return;
1871f5207b7SJohn Levon 	right = strip_expr(right->left);
1881f5207b7SJohn Levon 	if (right->type != EXPR_SYMBOL)
1891f5207b7SJohn Levon 		return;
1901f5207b7SJohn Levon 	if (!right->symbol->ident ||
1911f5207b7SJohn Levon 	    strcmp(right->symbol->ident->name, "__mptr") != 0)
1921f5207b7SJohn Levon 		return;
1931f5207b7SJohn Levon 	set_extra_expr_mod(expr->left, alloc_estate_range(valid_ptr_min_sval, valid_ptr_max_sval));
1941f5207b7SJohn Levon }
1951f5207b7SJohn Levon 
1961f5207b7SJohn Levon static int match_next_bit(struct expression *call, void *unused, struct range_list **rl)
1971f5207b7SJohn Levon {
1981f5207b7SJohn Levon 	struct expression *start_arg;
1991f5207b7SJohn Levon 	struct expression *size_arg;
2001f5207b7SJohn Levon 	struct symbol *type;
2011f5207b7SJohn Levon 	sval_t min, max, tmp;
2021f5207b7SJohn Levon 
2031f5207b7SJohn Levon 	size_arg = get_argument_from_call_expr(call->args, 1);
2041f5207b7SJohn Levon 	/* btw. there isn't a start_arg for find_first_bit() */
2051f5207b7SJohn Levon 	start_arg = get_argument_from_call_expr(call->args, 2);
2061f5207b7SJohn Levon 
2071f5207b7SJohn Levon 	type = get_type(call);
2081f5207b7SJohn Levon 	min = sval_type_val(type, 0);
2091f5207b7SJohn Levon 	max = sval_type_val(type, sizeof(long long) * 8);
2101f5207b7SJohn Levon 
2111f5207b7SJohn Levon 	if (get_implied_max(size_arg, &tmp) && tmp.uvalue < max.value)
2121f5207b7SJohn Levon 		max = tmp;
2131f5207b7SJohn Levon 	if (start_arg && get_implied_min(start_arg, &tmp) && !sval_is_negative(tmp))
2141f5207b7SJohn Levon 		min = tmp;
2151f5207b7SJohn Levon 	if (sval_cmp(min, max) > 0)
2161f5207b7SJohn Levon 		max = min;
2171f5207b7SJohn Levon 	min = sval_cast(type, min);
2181f5207b7SJohn Levon 	max = sval_cast(type, max);
2191f5207b7SJohn Levon 	*rl = alloc_rl(min, max);
2201f5207b7SJohn Levon 	return 1;
2211f5207b7SJohn Levon }
2221f5207b7SJohn Levon 
2231f5207b7SJohn Levon static int match_fls(struct expression *call, void *unused, struct range_list **rl)
2241f5207b7SJohn Levon {
2251f5207b7SJohn Levon 	struct expression *arg;
2261f5207b7SJohn Levon 	struct range_list *arg_rl;
2271f5207b7SJohn Levon 	sval_t zero = {};
2281f5207b7SJohn Levon 	sval_t start, end, sval;
2291f5207b7SJohn Levon 
2301f5207b7SJohn Levon 	start.type = &int_ctype;
2311f5207b7SJohn Levon 	start.value = 0;
2321f5207b7SJohn Levon 	end.type = &int_ctype;
2331f5207b7SJohn Levon 	end.value = 32;
2341f5207b7SJohn Levon 
2351f5207b7SJohn Levon 	arg = get_argument_from_call_expr(call->args, 0);
2361f5207b7SJohn Levon 	if (!get_implied_rl(arg, &arg_rl))
2371f5207b7SJohn Levon 		return 0;
2381f5207b7SJohn Levon 	if (rl_to_sval(arg_rl, &sval)) {
2391f5207b7SJohn Levon 		int i;
2401f5207b7SJohn Levon 
2411f5207b7SJohn Levon 		for (i = 63; i >= 0; i--) {
2421f5207b7SJohn Levon 			if (sval.uvalue & 1ULL << i)
2431f5207b7SJohn Levon 				break;
2441f5207b7SJohn Levon 		}
2451f5207b7SJohn Levon 		sval.value = i + 1;
2461f5207b7SJohn Levon 		*rl = alloc_rl(sval, sval);
2471f5207b7SJohn Levon 		return 1;
2481f5207b7SJohn Levon 	}
2491f5207b7SJohn Levon 	zero.type = rl_type(arg_rl);
2501f5207b7SJohn Levon 	if (!rl_has_sval(arg_rl, zero))
2511f5207b7SJohn Levon 		start.value = 1;
2521f5207b7SJohn Levon 	*rl = alloc_rl(start, end);
2531f5207b7SJohn Levon 	return 1;
2541f5207b7SJohn Levon }
2551f5207b7SJohn Levon 
2561f5207b7SJohn Levon 
2571f5207b7SJohn Levon 
2581f5207b7SJohn Levon static void find_module_init_exit(struct symbol_list *sym_list)
2591f5207b7SJohn Levon {
2601f5207b7SJohn Levon 	struct symbol *sym;
2611f5207b7SJohn Levon 	struct symbol *fn;
2621f5207b7SJohn Levon 	struct statement *stmt;
2631f5207b7SJohn Levon 	char *name;
2641f5207b7SJohn Levon 	int init;
2651f5207b7SJohn Levon 	int count;
2661f5207b7SJohn Levon 
2671f5207b7SJohn Levon 	/*
2681f5207b7SJohn Levon 	 * This is more complicated because Sparse ignores the "alias"
2691f5207b7SJohn Levon 	 * attribute.  I search backwards because module_init() is normally at
2701f5207b7SJohn Levon 	 * the end of the file.
2711f5207b7SJohn Levon 	 */
2721f5207b7SJohn Levon 	count = 0;
2731f5207b7SJohn Levon 	FOR_EACH_PTR_REVERSE(sym_list, sym) {
2741f5207b7SJohn Levon 		if (sym->type != SYM_NODE)
2751f5207b7SJohn Levon 			continue;
2761f5207b7SJohn Levon 		if (!(sym->ctype.modifiers & MOD_STATIC))
2771f5207b7SJohn Levon 			continue;
2781f5207b7SJohn Levon 		fn = get_base_type(sym);
2791f5207b7SJohn Levon 		if (!fn)
2801f5207b7SJohn Levon 			continue;
2811f5207b7SJohn Levon 		if (fn->type != SYM_FN)
2821f5207b7SJohn Levon 			continue;
2831f5207b7SJohn Levon 		if (!sym->ident)
2841f5207b7SJohn Levon 			continue;
2851f5207b7SJohn Levon 		if (!fn->inline_stmt)
2861f5207b7SJohn Levon 			continue;
2871f5207b7SJohn Levon 		if (strcmp(sym->ident->name, "__inittest") == 0)
2881f5207b7SJohn Levon 			init = 1;
2891f5207b7SJohn Levon 		else if (strcmp(sym->ident->name, "__exittest") == 0)
2901f5207b7SJohn Levon 			init = 0;
2911f5207b7SJohn Levon 		else
2921f5207b7SJohn Levon 			continue;
2931f5207b7SJohn Levon 
2941f5207b7SJohn Levon 		count++;
2951f5207b7SJohn Levon 
2961f5207b7SJohn Levon 		stmt = first_ptr_list((struct ptr_list *)fn->inline_stmt->stmts);
2971f5207b7SJohn Levon 		if (!stmt || stmt->type != STMT_RETURN)
2981f5207b7SJohn Levon 			continue;
2991f5207b7SJohn Levon 		name = expr_to_var(stmt->ret_value);
3001f5207b7SJohn Levon 		if (!name)
3011f5207b7SJohn Levon 			continue;
3021f5207b7SJohn Levon 		if (init)
3031f5207b7SJohn Levon 			sql_insert_function_ptr(name, "(struct module)->init");
3041f5207b7SJohn Levon 		else
3051f5207b7SJohn Levon 			sql_insert_function_ptr(name, "(struct module)->exit");
3061f5207b7SJohn Levon 		free_string(name);
3071f5207b7SJohn Levon 		if (count >= 2)
3081f5207b7SJohn Levon 			return;
3091f5207b7SJohn Levon 	} END_FOR_EACH_PTR_REVERSE(sym);
3101f5207b7SJohn Levon }
3111f5207b7SJohn Levon 
3121f5207b7SJohn Levon static void match_end_file(struct symbol_list *sym_list)
3131f5207b7SJohn Levon {
3141f5207b7SJohn Levon 	struct symbol *sym;
3151f5207b7SJohn Levon 
3161f5207b7SJohn Levon 	/* find the last static symbol in the file */
3171f5207b7SJohn Levon 	FOR_EACH_PTR_REVERSE(sym_list, sym) {
3181f5207b7SJohn Levon 		if (!(sym->ctype.modifiers & MOD_STATIC))
3191f5207b7SJohn Levon 			continue;
3201f5207b7SJohn Levon 		if (!sym->scope)
3211f5207b7SJohn Levon 			continue;
3221f5207b7SJohn Levon 		find_module_init_exit(sym->scope->symbols);
3231f5207b7SJohn Levon 		return;
3241f5207b7SJohn Levon 	} END_FOR_EACH_PTR_REVERSE(sym);
3251f5207b7SJohn Levon }
3261f5207b7SJohn Levon 
3271f5207b7SJohn Levon static struct expression *get_val_expr(struct expression *expr)
3281f5207b7SJohn Levon {
3291f5207b7SJohn Levon 	struct symbol *sym, *val;
3301f5207b7SJohn Levon 
3311f5207b7SJohn Levon 	if (expr->type != EXPR_DEREF)
3321f5207b7SJohn Levon 		return NULL;
3331f5207b7SJohn Levon 	expr = expr->deref;
3341f5207b7SJohn Levon 	if (expr->type != EXPR_SYMBOL)
3351f5207b7SJohn Levon 		return NULL;
3361f5207b7SJohn Levon 	if (strcmp(expr->symbol_name->name, "__u") != 0)
3371f5207b7SJohn Levon 		return NULL;
3381f5207b7SJohn Levon 	sym = get_base_type(expr->symbol);
3391f5207b7SJohn Levon 	val = first_ptr_list((struct ptr_list *)sym->symbol_list);
3401f5207b7SJohn Levon 	if (!val || strcmp(val->ident->name, "__val") != 0)
3411f5207b7SJohn Levon 		return NULL;
3421f5207b7SJohn Levon 	return member_expression(expr, '.', val->ident);
3431f5207b7SJohn Levon }
3441f5207b7SJohn Levon 
3451f5207b7SJohn Levon static void match__write_once_size(const char *fn, struct expression *call,
3461f5207b7SJohn Levon 			       void *unused)
3471f5207b7SJohn Levon {
3481f5207b7SJohn Levon 	struct expression *dest, *data, *assign;
3491f5207b7SJohn Levon 	struct range_list *rl;
3501f5207b7SJohn Levon 
3511f5207b7SJohn Levon 	dest = get_argument_from_call_expr(call->args, 0);
3521f5207b7SJohn Levon 	if (dest->type != EXPR_PREOP || dest->op != '&')
3531f5207b7SJohn Levon 		return;
3541f5207b7SJohn Levon 	dest = strip_expr(dest->unop);
3551f5207b7SJohn Levon 
3561f5207b7SJohn Levon 	data = get_argument_from_call_expr(call->args, 1);
3571f5207b7SJohn Levon 	data = get_val_expr(data);
3581f5207b7SJohn Levon 	if (!data)
3591f5207b7SJohn Levon 		return;
3601f5207b7SJohn Levon 	get_absolute_rl(data, &rl);
3611f5207b7SJohn Levon 	assign = assign_expression(dest, '=', data);
3621f5207b7SJohn Levon 
3631f5207b7SJohn Levon 	__in_fake_assign++;
3641f5207b7SJohn Levon 	__split_expr(assign);
3651f5207b7SJohn Levon 	__in_fake_assign--;
3661f5207b7SJohn Levon }
3671f5207b7SJohn Levon 
3681f5207b7SJohn Levon static void match__read_once_size(const char *fn, struct expression *call,
3691f5207b7SJohn Levon 			       void *unused)
3701f5207b7SJohn Levon {
3711f5207b7SJohn Levon 	struct expression *dest, *data, *assign;
3721f5207b7SJohn Levon 	struct symbol *type, *val_sym;
3731f5207b7SJohn Levon 
3741f5207b7SJohn Levon 	/*
3751f5207b7SJohn Levon 	 * We want to change:
3761f5207b7SJohn Levon 	 *	__read_once_size_nocheck(&(x), __u.__c, sizeof(x));
3771f5207b7SJohn Levon 	 * into a fake assignment:
3781f5207b7SJohn Levon 	 *	__u.val = x;
3791f5207b7SJohn Levon 	 *
3801f5207b7SJohn Levon 	 */
3811f5207b7SJohn Levon 
3821f5207b7SJohn Levon 	data = get_argument_from_call_expr(call->args, 0);
3831f5207b7SJohn Levon 	if (data->type != EXPR_PREOP || data->op != '&')
3841f5207b7SJohn Levon 		return;
3851f5207b7SJohn Levon 	data = strip_parens(data->unop);
3861f5207b7SJohn Levon 
3871f5207b7SJohn Levon 	dest = get_argument_from_call_expr(call->args, 1);
3881f5207b7SJohn Levon 	if (dest->type != EXPR_DEREF || dest->op != '.')
3891f5207b7SJohn Levon 		return;
3901f5207b7SJohn Levon 	if (!dest->member || strcmp(dest->member->name, "__c") != 0)
3911f5207b7SJohn Levon 		return;
3921f5207b7SJohn Levon 	dest = dest->deref;
3931f5207b7SJohn Levon 	type = get_type(dest);
3941f5207b7SJohn Levon 	if (!type)
3951f5207b7SJohn Levon 		return;
3961f5207b7SJohn Levon 	val_sym = first_ptr_list((struct ptr_list *)type->symbol_list);
3971f5207b7SJohn Levon 	dest = member_expression(dest, '.', val_sym->ident);
3981f5207b7SJohn Levon 
3991f5207b7SJohn Levon 	assign = assign_expression(dest, '=', data);
4001f5207b7SJohn Levon 	__in_fake_assign++;
4011f5207b7SJohn Levon 	__split_expr(assign);
4021f5207b7SJohn Levon 	__in_fake_assign--;
4031f5207b7SJohn Levon }
4041f5207b7SJohn Levon 
405*efe51d0cSJohn Levon bool is_ignored_kernel_data(const char *name)
406*efe51d0cSJohn Levon {
407*efe51d0cSJohn Levon 	if (option_project != PROJ_KERNEL)
408*efe51d0cSJohn Levon 		return false;
409*efe51d0cSJohn Levon 
410*efe51d0cSJohn Levon 	/*
411*efe51d0cSJohn Levon 	 * On the file I was looking at lockdep was 25% of the DB.
412*efe51d0cSJohn Levon 	 */
413*efe51d0cSJohn Levon 	if (strstr(name, ".dep_map."))
414*efe51d0cSJohn Levon 		return true;
415*efe51d0cSJohn Levon 	if (strstr(name, ".lockdep_map."))
416*efe51d0cSJohn Levon 		return true;
417*efe51d0cSJohn Levon 	return false;
418*efe51d0cSJohn Levon }
419*efe51d0cSJohn Levon 
4201f5207b7SJohn Levon void check_kernel(int id)
4211f5207b7SJohn Levon {
4221f5207b7SJohn Levon 	if (option_project != PROJ_KERNEL)
4231f5207b7SJohn Levon 		return;
4241f5207b7SJohn Levon 
425*efe51d0cSJohn Levon 	err_ptr_min.type = &ptr_ctype;
426*efe51d0cSJohn Levon 	err_ptr_min.value = -4095;
427*efe51d0cSJohn Levon 	err_ptr_max.type = &ptr_ctype;
428*efe51d0cSJohn Levon 	err_ptr_max.value = -1l;
429*efe51d0cSJohn Levon 	null_ptr.type = &ptr_ctype;
430*efe51d0cSJohn Levon 	null_ptr.value = 0;
431*efe51d0cSJohn Levon 
432*efe51d0cSJohn Levon 	err_ptr_min = sval_cast(&ptr_ctype, err_ptr_min);
433*efe51d0cSJohn Levon 	err_ptr_max = sval_cast(&ptr_ctype, err_ptr_max);
434*efe51d0cSJohn Levon 
4351f5207b7SJohn Levon 	add_implied_return_hook("ERR_PTR", &implied_err_cast_return, NULL);
4361f5207b7SJohn Levon 	add_implied_return_hook("ERR_CAST", &implied_err_cast_return, NULL);
4371f5207b7SJohn Levon 	add_implied_return_hook("PTR_ERR", &implied_err_cast_return, NULL);
4381f5207b7SJohn Levon 	add_hook(hack_ERR_PTR, AFTER_DEF_HOOK);
4391f5207b7SJohn Levon 	return_implies_state("IS_ERR_OR_NULL", 0, 0, &match_param_valid_ptr, (void *)0);
4401f5207b7SJohn Levon 	return_implies_state("IS_ERR_OR_NULL", 1, 1, &match_param_err_or_null, (void *)0);
4411f5207b7SJohn Levon 	return_implies_state("IS_ERR", 0, 0, &match_not_err, NULL);
4421f5207b7SJohn Levon 	return_implies_state("IS_ERR", 1, 1, &match_err, NULL);
4431f5207b7SJohn Levon 	return_implies_state("tomoyo_memory_ok", 1, 1, &match_param_valid_ptr, (void *)0);
4441f5207b7SJohn Levon 
4451f5207b7SJohn Levon 	add_macro_assign_hook_extra("container_of", &match_container_of_macro, NULL);
4461f5207b7SJohn Levon 	add_hook(match_container_of, ASSIGNMENT_HOOK);
4471f5207b7SJohn Levon 
4481f5207b7SJohn Levon 	add_implied_return_hook("find_next_bit", &match_next_bit, NULL);
4491f5207b7SJohn Levon 	add_implied_return_hook("find_next_zero_bit", &match_next_bit, NULL);
4501f5207b7SJohn Levon 	add_implied_return_hook("find_first_bit", &match_next_bit, NULL);
4511f5207b7SJohn Levon 	add_implied_return_hook("find_first_zero_bit", &match_next_bit, NULL);
4521f5207b7SJohn Levon 
4531f5207b7SJohn Levon 	add_implied_return_hook("fls", &match_fls, NULL);
4541f5207b7SJohn Levon 	add_implied_return_hook("fls64", &match_fls, NULL);
4551f5207b7SJohn Levon 
4561f5207b7SJohn Levon 	add_function_hook("__ftrace_bad_type", &__match_nullify_path_hook, NULL);
4571f5207b7SJohn Levon 	add_function_hook("__write_once_size", &match__write_once_size, NULL);
4581f5207b7SJohn Levon 
4591f5207b7SJohn Levon 	add_function_hook("__read_once_size", &match__read_once_size, NULL);
4601f5207b7SJohn Levon 	add_function_hook("__read_once_size_nocheck", &match__read_once_size, NULL);
4611f5207b7SJohn Levon 
4621f5207b7SJohn Levon 	if (option_info)
4631f5207b7SJohn Levon 		add_hook(match_end_file, END_FILE_HOOK);
4641f5207b7SJohn Levon }
465