From 36208e6037b452fb2e7bdb7faf514dd98e531e26 Mon Sep 17 00:00:00 2001 From: Martin Liska Date: Thu, 19 Oct 2017 09:50:48 +0200 Subject: [PATCH] Do not instrument use-after-scope for vars with large alignment (PR sanitizer/82517). 2017-10-19 Martin Liska PR sanitizer/82517 * gimplify.c (gimplify_decl_expr): Do not instrument variables that have a large alignment. (gimplify_target_expr): Likewise. 2017-10-19 Martin Liska PR sanitizer/82517 * gcc.dg/asan/pr82517.c: New test. From-SVN: r253879 --- gcc/ChangeLog | 7 +++++ gcc/gimplify.c | 5 +++- gcc/testsuite/ChangeLog | 5 ++++ gcc/testsuite/gcc.dg/asan/pr82517.c | 43 +++++++++++++++++++++++++++++ 4 files changed, 59 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/gcc.dg/asan/pr82517.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index a139a824d35..e60a49f99cc 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2017-10-19 Martin Liska + + PR sanitizer/82517 + * gimplify.c (gimplify_decl_expr): Do not instrument variables + that have a large alignment. + (gimplify_target_expr): Likewise. + 2017-10-18 Segher Boessenkool PR rtl-optimization/82602 diff --git a/gcc/gimplify.c b/gcc/gimplify.c index c3fd6ace84e..19411c98fce 100644 --- a/gcc/gimplify.c +++ b/gcc/gimplify.c @@ -1656,6 +1656,7 @@ gimplify_decl_expr (tree *stmt_p, gimple_seq *seq_p) && TREE_ADDRESSABLE (decl) && !TREE_STATIC (decl) && !DECL_HAS_VALUE_EXPR_P (decl) + && DECL_ALIGN (decl) <= MAX_SUPPORTED_STACK_ALIGNMENT && dbg_cnt (asan_use_after_scope)) { asan_poisoned_variables->add (decl); @@ -6505,7 +6506,9 @@ gimplify_target_expr (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p) clobber = build2 (MODIFY_EXPR, TREE_TYPE (temp), temp, clobber); gimple_push_cleanup (temp, clobber, false, pre_p, true); } - if (asan_poisoned_variables && dbg_cnt (asan_use_after_scope)) + if (asan_poisoned_variables + && DECL_ALIGN (temp) <= MAX_SUPPORTED_STACK_ALIGNMENT + && dbg_cnt (asan_use_after_scope)) { tree asan_cleanup = build_asan_poison_call_expr (temp); if (asan_cleanup) diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 39f2edd544e..a30186a2f49 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2017-10-19 Martin Liska + + PR sanitizer/82517 + * gcc.dg/asan/pr82517.c: New test. + 2017-10-19 Jakub Jelinek PR fortran/82568 diff --git a/gcc/testsuite/gcc.dg/asan/pr82517.c b/gcc/testsuite/gcc.dg/asan/pr82517.c new file mode 100644 index 00000000000..c7743ecb8b1 --- /dev/null +++ b/gcc/testsuite/gcc.dg/asan/pr82517.c @@ -0,0 +1,43 @@ +/* PR sanitizer/82517. */ + +static int *pp; + +void +baz () +{ + return; +} + +void +bar (int *p) +{ + *p = 1; +} + +void +foo (int a) +{ + if (a == 2) + { + lab: + baz (); + return; + } + if (a > 1) + { + int x __attribute__ ((aligned (256))); + pp = &x; + bar (&x); + if (!x) + goto lab; + } +} + +int +main (int argc, char **argv) +{ + foo (4); + foo (3); + + return 0; +} -- 2.30.2