diff options
author | shyouhei <shyouhei@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2018-09-11 09:48:58 +0000 |
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committer | shyouhei <shyouhei@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2018-09-11 09:48:58 +0000 |
commit | c2bfb4e93c674347b7eb09a30856e3d75f74cf4d (patch) | |
tree | b898add4e9f9ab117aebcad189d47e79984c2f16 /tool | |
parent | ecda2d23d593eea81a4daf97ec0d74945fa96baf (diff) |
add new instruction attribute called leaf
An instruction is leaf if it has no rb_funcall inside. In order to
check this property, we introduce stack canary which is a random
number collected at runtime. Stack top is always filled with this
number and checked for stack smashing operations, when VM_CHECK_MODE.
[GH-1947]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@64677 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Diffstat (limited to 'tool')
-rwxr-xr-x | tool/ruby_vm/models/bare_instructions.rb | 8 | ||||
-rw-r--r-- | tool/ruby_vm/views/_insn_entry.erb | 21 | ||||
-rw-r--r-- | tool/ruby_vm/views/_leaf_helpers.erb | 105 | ||||
-rw-r--r-- | tool/ruby_vm/views/insns_info.inc.erb | 1 |
4 files changed, 135 insertions, 0 deletions
diff --git a/tool/ruby_vm/models/bare_instructions.rb b/tool/ruby_vm/models/bare_instructions.rb index d2ff1341a0..5c27af3a38 100755 --- a/tool/ruby_vm/models/bare_instructions.rb +++ b/tool/ruby_vm/models/bare_instructions.rb @@ -105,6 +105,10 @@ class RubyVM::BareInstructions /\b(false|0)\b/ !~ @attrs['handles_sp'].expr.expr end + def complicated_return_values? + @sig[:ret].any? {|i| i == '...' } + end + def inspect sprintf "#<%s %s@%s:%d>", self.class.name, @name, @loc[0], @loc[1] end @@ -130,6 +134,10 @@ class RubyVM::BareInstructions generate_attribute 'rb_num_t', 'width', width generate_attribute 'rb_snum_t', 'sp_inc', rets.size - pops.size generate_attribute 'bool', 'handles_sp', false + generate_attribute 'bool', 'leaf', opes.all? {|o| + # Insn with ISEQ should yield it; can never be a leaf. + o[:type] != 'ISEQ' + } end def typesplit a diff --git a/tool/ruby_vm/views/_insn_entry.erb b/tool/ruby_vm/views/_insn_entry.erb index e3e3ea42ea..90a489f624 100644 --- a/tool/ruby_vm/views/_insn_entry.erb +++ b/tool/ruby_vm/views/_insn_entry.erb @@ -13,6 +13,12 @@ INSN_ENTRY(<%= insn.name %>) %# NAME_OF_CURRENT_INSN is used in vm_exec.h # define NAME_OF_CURRENT_INSN <%= insn.name %> # define INSN_ATTR(x) <%= insn.call_attribute(' ## x ## ') %> +% unless insn.complicated_return_values? +# if VM_CHECK_MODE > 0 + bool leaf; + VALUE *canary; +# endif +% end % unless insn.declarations.empty? <%= insn.declarations.join(";\n ") %>; @@ -33,12 +39,27 @@ INSN_ENTRY(<%= insn.name %>) % if insn.handles_sp? POPN(INSN_ATTR(popn)); % end +% unless insn.complicated_return_values? +#if VM_CHECK_MODE > 0 + if ((leaf = INSN_ATTR(leaf))) { + canary = STACK_ADDR_FROM_TOP(-1); + *canary = vm_stack_canary; + } +#endif +% end COLLECT_USAGE_INSN(INSN_ATTR(bin)); % insn.opes.each_with_index do |ope, i| COLLECT_USAGE_OPERAND(INSN_ATTR(bin), <%= i %>, <%= ope[:name] %>); % end <%= render_c_expr insn.expr -%> CHECK_VM_STACK_OVERFLOW_FOR_INSN(VM_REG_CFP, INSN_ATTR(retn)); +% unless insn.complicated_return_values? +#if VM_CHECK_MODE > 0 + if (leaf && (*canary != vm_stack_canary)) { + vm_canary_is_found_dead(INSN_ATTR(bin), *canary); + } +#endif +% end % if insn.handles_sp? % insn.rets.reverse_each do |ret| PUSH(<%= insn.cast_to_VALUE ret %>); diff --git a/tool/ruby_vm/views/_leaf_helpers.erb b/tool/ruby_vm/views/_leaf_helpers.erb new file mode 100644 index 0000000000..00c2e3882a --- /dev/null +++ b/tool/ruby_vm/views/_leaf_helpers.erb @@ -0,0 +1,105 @@ +%# -*- mode:c; style:ruby; coding: utf-8; indent-tabs-mode: nil -*- +%# Copyright (c) 2018 Urabe, Shyouhei. All rights reserved. +%# +%# This file is a part of the programming language Ruby. Permission is hereby +%# granted, to either redistribute and/or modify this file, provided that the +%# conditions mentioned in the file COPYING are met. Consult the file for +%# details. +%; + +static bool +leafness_of_getglobal(VALUE gentry) +{ + const struct rb_global_entry *e = (void *)gentry; + + if (UNLIKELY(rb_gvar_is_traced(e))) { + return false; + } + else { + /* We cannot write this function using a switch() because a + * case label cannot be a function pointer. */ + static rb_gvar_getter_t *const whitelist[] = { + rb_gvar_val_getter, + rb_gvar_var_getter, + rb_gvar_undef_getter, + }; + rb_gvar_getter_t *f = rb_gvar_getter_function_of(e); + int i; + + for (i = 0; i < numberof(whitelist); i++) { + if (f == whitelist[i]) { + return true; + } + } + return false; + } +} + +static bool +leafness_of_setglobal(VALUE gentry) +{ + const struct rb_global_entry *e = (void *)gentry; + + if (UNLIKELY(rb_gvar_is_traced(e))) { + return false; + } + else { + /* We cannot write this function using a switch() because a + * case label cannot be a function pointer. */ + static rb_gvar_setter_t *const whitelist[] = { + rb_gvar_val_setter, + rb_gvar_readonly_setter, + rb_gvar_var_setter, + rb_gvar_undef_setter, + }; + rb_gvar_setter_t *f = rb_gvar_setter_function_of(e); + int i; + + for (i = 0; i < numberof(whitelist); i++) { + if (f == whitelist[i]) { + return true; + } + } + return false; + } +} + +#include "iseq.h" + +static bool +leafness_of_defined(rb_num_t op_type) +{ + /* see also: vm_insnhelper.c:vm_defined() */ + switch (op_type) { + case DEFINED_IVAR: + case DEFINED_IVAR2: + case DEFINED_GVAR: + case DEFINED_CVAR: + case DEFINED_YIELD: + case DEFINED_REF: + case DEFINED_ZSUPER: + return false; + case DEFINED_CONST: + /* has rb_autoload_load(); */ + return false; + case DEFINED_FUNC: + case DEFINED_METHOD: + /* calls #respond_to_missing? */ + return false; + default: + rb_bug("unknown operand %ld: blame @shyouhei.", op_type); + } +} + +static bool +leafness_of_checkmatch(rb_num_t flag) +{ + /* see also: vm_insnhelper.c:check_match() */ + if (flag == VM_CHECKMATCH_TYPE_WHEN) { + return true; + } + else { + /* has rb_funcallv() */ + return false; + } +} diff --git a/tool/ruby_vm/views/insns_info.inc.erb b/tool/ruby_vm/views/insns_info.inc.erb index e08a15e5ef..67fcebfc42 100644 --- a/tool/ruby_vm/views/insns_info.inc.erb +++ b/tool/ruby_vm/views/insns_info.inc.erb @@ -15,5 +15,6 @@ <%= render 'insn_name_info' %> <%= render 'insn_len_info' %> <%= render 'insn_operand_info' %> +<%= render 'leaf_helpers' %> <%= render 'attributes' %> <%= render 'insn_stack_increase' %> |