From 84150137640481ac139325bf8cc665dd47fca95c Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= Date: Thu, 26 Apr 2018 22:23:04 +0200 Subject: beam_validator: Verify Y registers in exception-causing instructions When an exception is handled, the stack will be scanned. Therefore all Y registers must be initialized. --- lib/compiler/src/beam_validator.erl | 7 +++++++ lib/compiler/test/beam_validator_SUITE.erl | 4 ++-- 2 files changed, 9 insertions(+), 2 deletions(-) diff --git a/lib/compiler/src/beam_validator.erl b/lib/compiler/src/beam_validator.erl index 962f17d83c..86aa12e19b 100644 --- a/lib/compiler/src/beam_validator.erl +++ b/lib/compiler/src/beam_validator.erl @@ -267,13 +267,17 @@ valfun_1(_I, #vst{current=none}=Vst) -> Vst; valfun_1({badmatch,Src}, Vst) -> assert_term(Src, Vst), + verify_y_init(Vst), kill_state(Vst); valfun_1({case_end,Src}, Vst) -> assert_term(Src, Vst), + verify_y_init(Vst), kill_state(Vst); valfun_1(if_end, Vst) -> + verify_y_init(Vst), kill_state(Vst); valfun_1({try_case_end,Src}, Vst) -> + verify_y_init(Vst), assert_term(Src, Vst), kill_state(Vst); %% Instructions that can not cause exceptions @@ -375,6 +379,9 @@ valfun_1({call_ext,Live,Func}=I, Vst) -> case return_type(Func, Vst) of exception -> verify_live(Live, Vst), + %% The stack will be scanned, so Y registers + %% must be initialized. + verify_y_init(Vst), kill_state(Vst); _ -> valfun_2(I, Vst) diff --git a/lib/compiler/test/beam_validator_SUITE.erl b/lib/compiler/test/beam_validator_SUITE.erl index 3af71559ae..41f2957dc1 100644 --- a/lib/compiler/test/beam_validator_SUITE.erl +++ b/lib/compiler/test/beam_validator_SUITE.erl @@ -157,8 +157,8 @@ call_last(Config) when is_list(Config) -> merge_undefined(Config) when is_list(Config) -> Errors = do_val(merge_undefined, Config), [{{t,handle_call,2}, - {{call_ext,2,{extfunc,debug,filter,2}}, - 22, + {{call_ext,1,{extfunc,erlang,exit,1}}, + 10, {uninitialized_reg,{y,0}}}}] = Errors, ok. -- cgit v1.2.3