From 9faf8348621ae6ab583af593d67ac424300a2bad Mon Sep 17 00:00:00 2001 From: David Malcolm Date: Fri, 16 Jul 2021 15:49:17 -0400 Subject: analyzer: add region_model::check_region_access I've been experimenting with various new diagnostics that require a common place for the analyzer to check the validity of reads or writes to memory (e.g. buffer overflow). As preliminary work, this patch adds new region_model::check_region_for_{read|write} functions which are called anywhere that the analyzer "sees" memory being read from or written to (via region_model::get_store_value and region_model::set_value). This takes over the hardcoded calls to check_for_writable_region (allowing for other kinds of checks on writes); checking reads is currently a no-op. gcc/analyzer/ChangeLog: * analyzer.h (enum access_direction): New. * engine.cc (exploded_node::on_longjmp): Update for new param of get_store_value. * program-state.cc (program_state::prune_for_point): Likewise. * region-model-impl-calls.cc (region_model::impl_call_memcpy): Replace call to check_for_writable_region with call to check_region_for_write. (region_model::impl_call_memset): Likewise. (region_model::impl_call_strcpy): Likewise. * region-model-reachability.cc (reachable_regions::add): Update for new param of get_store_value. * region-model.cc (region_model::get_rvalue_1): Likewise, also for get_rvalue_for_bits. (region_model::get_store_value): Add ctxt param and use it to call check_region_for_read. (region_model::get_rvalue_for_bits): Add ctxt param and use it to call get_store_value. (region_model::check_region_access): New. (region_model::check_region_for_write): New. (region_model::check_region_for_read): New. (region_model::set_value): Update comment. Replace call to check_for_writable_region with call to check_region_for_write. * region-model.h (region_model::get_rvalue_for_bits): Add ctxt param. (region_model::get_store_value): Add ctxt param. (region_model::check_region_access): New decl. (region_model::check_region_for_write): New decl. (region_model::check_region_for_read): New decl. * region.cc (region_model::copy_region): Update call to get_store_value. * svalue.cc (initial_svalue::implicitly_live_p): Likewise. Signed-off-by: David Malcolm --- gcc/analyzer/program-state.cc | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'gcc/analyzer/program-state.cc') diff --git a/gcc/analyzer/program-state.cc b/gcc/analyzer/program-state.cc index 3081217..ccfe7b0 100644 --- a/gcc/analyzer/program-state.cc +++ b/gcc/analyzer/program-state.cc @@ -1082,7 +1082,7 @@ program_state::prune_for_point (exploded_graph &eg, temporaries keep the value reachable until the frame is popped. */ const svalue *sval - = new_state.m_region_model->get_store_value (reg); + = new_state.m_region_model->get_store_value (reg, NULL); if (!new_state.can_purge_p (eg.get_ext_state (), sval) && SSA_NAME_VAR (ssa_name)) { -- cgit v1.1