| Message ID | 136220ee-a743-dc68-019a-7ae8abce8d12@suse.cz |
|---|---|
| State | New |
| Headers | show |
On Tue, Jul 04, 2017 at 09:47:29AM +0200, Martin Liška wrote: > As mentioned in https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81040#c15, the sanitization is > done only when one uses use-after-scope. That's caused by fact that I decorated the newly > created auto variables with DECL_ARTIFICIAL = 1. Because of that > > static inline bool > asan_protect_stack_decl (tree decl) > { > return DECL_P (decl) > && (!DECL_ARTIFICIAL (decl) > || (asan_sanitize_use_after_scope () && TREE_ADDRESSABLE (decl))); > } > > returns false. I hope not marking the variable as DECL_ARTIFICIAL will work fine? > Or am I missing something? Well, you should make sure the debug info is correct. Which means ideally that there is just one DW_TAG_formal_parameter and no DW_TAG_variable for the parameter. For the addressable parameters I hope the corresponding artificial vars just live in memory for the whole rest of the scope, at least for the case where you emit a debug bind (hope it is after the assignment to the artificial var) I think it should be fine to set DECL_IGNORED_P on the artificial var instead of DECL_ARTIFICIAL. For the other case where there is DECL_VALUE_EXPR, perhaps try it too and see what you get. Jakub
From b79133e3c9ad41b44f0a12c574fc1d0b8348ad89 Mon Sep 17 00:00:00 2001 From: marxin <mliska@suse.cz> Date: Tue, 4 Jul 2017 09:22:23 +0200 Subject: [PATCH] Enable addressable params sanitization with --param asan-stack=1. gcc/ChangeLog: 2017-07-04 Martin Liska <mliska@suse.cz> PR sanitizer/81040 * sanopt.c (sanitize_rewrite_addressable_params): Do not decorate variable as DECL_ARTIFICIAL in order to sanitize it. gcc/testsuite/ChangeLog: 2017-07-04 Martin Liska <mliska@suse.cz> PR sanitizer/81040 * g++.dg/asan/function-argument-1.C: Run the test-case w/o use-after-scope sanitization. --- gcc/sanopt.c | 1 - gcc/testsuite/g++.dg/asan/function-argument-1.C | 1 + 2 files changed, 1 insertion(+), 1 deletion(-) diff --git a/gcc/sanopt.c b/gcc/sanopt.c index 7692f6a9db7..8c80ff37d4d 100644 --- a/gcc/sanopt.c +++ b/gcc/sanopt.c @@ -905,7 +905,6 @@ sanitize_rewrite_addressable_params (function *fun) tree var = build_decl (DECL_SOURCE_LOCATION (arg), VAR_DECL, DECL_NAME (arg), type); TREE_ADDRESSABLE (var) = 1; - DECL_ARTIFICIAL (var) = 1; gimple_add_tmp_var (var); diff --git a/gcc/testsuite/g++.dg/asan/function-argument-1.C b/gcc/testsuite/g++.dg/asan/function-argument-1.C index 148c4628316..bdbb37a44a4 100644 --- a/gcc/testsuite/g++.dg/asan/function-argument-1.C +++ b/gcc/testsuite/g++.dg/asan/function-argument-1.C @@ -1,5 +1,6 @@ // { dg-do run } // { dg-shouldfail "asan" } +// { dg-options "-fsanitize=address -fno-sanitize-address-use-after-scope" } struct A { -- 2.13.2
Hello. As mentioned in https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81040#c15, the sanitization is done only when one uses use-after-scope. That's caused by fact that I decorated the newly created auto variables with DECL_ARTIFICIAL = 1. Because of that static inline bool asan_protect_stack_decl (tree decl) { return DECL_P (decl) && (!DECL_ARTIFICIAL (decl) || (asan_sanitize_use_after_scope () && TREE_ADDRESSABLE (decl))); } returns false. I hope not marking the variable as DECL_ARTIFICIAL will work fine? Or am I missing something? Thanks, Martin