From c3da495616f26855ac6b2522e8bbecd7e718074e Mon Sep 17 00:00:00 2001 From: Maxim Ostapenko Date: Fri, 8 Apr 2016 10:46:13 +0000 Subject: re PR sanitizer/70541 (unnoticed invalid dereference when using address sanitizer) 2016-04-08 Maxim Ostapenko PR sanitizer/70541 * asan.c (instrument_derefs): If we get unknown location, extract it with EXPR_LOCATION. (maybe_instrument_call): Instrument gimple_call's arguments if needed. * c-c++-common/asan/pr70541.c: New test. From-SVN: r234827 --- gcc/asan.c | 28 +++++++++++++++++++++++++--- 1 file changed, 25 insertions(+), 3 deletions(-) (limited to 'gcc/asan.c') diff --git a/gcc/asan.c b/gcc/asan.c index 47bfdcd..71095fb 100644 --- a/gcc/asan.c +++ b/gcc/asan.c @@ -1766,6 +1766,8 @@ instrument_derefs (gimple_stmt_iterator *iter, tree t, tree type, base; HOST_WIDE_INT size_in_bytes; + if (location == UNKNOWN_LOCATION) + location = EXPR_LOCATION (t); type = TREE_TYPE (t); switch (TREE_CODE (t)) @@ -2049,6 +2051,7 @@ maybe_instrument_call (gimple_stmt_iterator *iter) gsi_insert_before (iter, g, GSI_SAME_STMT); } + bool instrumented = false; if (gimple_store_p (stmt)) { tree ref_expr = gimple_call_lhs (stmt); @@ -2056,11 +2059,30 @@ maybe_instrument_call (gimple_stmt_iterator *iter) gimple_location (stmt), /*is_store=*/true); - gsi_next (iter); - return true; + instrumented = true; } - return false; + /* Walk through gimple_call arguments and check them id needed. */ + unsigned args_num = gimple_call_num_args (stmt); + for (unsigned i = 0; i < args_num; ++i) + { + tree arg = gimple_call_arg (stmt, i); + /* If ARG is not a non-aggregate register variable, compiler in general + creates temporary for it and pass it as argument to gimple call. + But in some cases, e.g. when we pass by value a small structure that + fits to register, compiler can avoid extra overhead by pulling out + these temporaries. In this case, we should check the argument. */ + if (!is_gimple_reg (arg) && !is_gimple_min_invariant (arg)) + { + instrument_derefs (iter, arg, + gimple_location (stmt), + /*is_store=*/false); + instrumented = true; + } + } + if (instrumented) + gsi_next (iter); + return instrumented; } /* Walk each instruction of all basic block and instrument those that -- cgit v1.1