From 3219822bb549a9d0d40ff29463f0bfe7d1eedd37 Mon Sep 17 00:00:00 2001 From: Richard Carlsson Date: Sun, 26 Apr 2015 16:29:53 +0200 Subject: Fix segfault in module_info for deleted modules Add a check to protect from segfault when erlang:get_module_info/1/2 is called on a deleted module (i.e. with no current code). Also refactor erts_module_info_0/1 to avoid repeated calls to erts_active_code_ix() and remove some obsolete comments. Add test for module_info on deleted modules. --- erts/emulator/beam/beam_load.c | 181 ++++++++++++++--------------------------- 1 file changed, 63 insertions(+), 118 deletions(-) (limited to 'erts/emulator/beam/beam_load.c') diff --git a/erts/emulator/beam/beam_load.c b/erts/emulator/beam/beam_load.c index 0d40201934..41ce1659d4 100644 --- a/erts/emulator/beam/beam_load.c +++ b/erts/emulator/beam/beam_load.c @@ -525,13 +525,16 @@ static void new_literal_patch(LoaderState* stp, int pos); static void new_string_patch(LoaderState* stp, int pos); static Uint new_literal(LoaderState* stp, Eterm** hpp, Uint heap_size); static int genopargcompare(GenOpArg* a, GenOpArg* b); -static Eterm exported_from_module(Process* p, Eterm mod); -static Eterm functions_in_module(Process* p, Eterm mod); -static Eterm attributes_for_module(Process* p, Eterm mod); -static Eterm compilation_info_for_module(Process* p, Eterm mod); -static Eterm md5_of_module(Process* p, Eterm mod); -static Eterm has_native(Process* p, Eterm mod); -static Eterm native_addresses(Process* p, Eterm mod); +static Eterm get_module_info(Process* p, ErtsCodeIndex code_ix, + BeamInstr* code, Eterm module, Eterm what); +static Eterm exported_from_module(Process* p, ErtsCodeIndex code_ix, + Eterm mod); +static Eterm functions_in_module(Process* p, BeamInstr* code); +static Eterm attributes_for_module(Process* p, BeamInstr* code); +static Eterm compilation_info_for_module(Process* p, BeamInstr* code); +static Eterm md5_of_module(Process* p, BeamInstr* code); +static Eterm has_native(BeamInstr* code); +static Eterm native_addresses(Process* p, BeamInstr* code); int patch_funentries(Eterm Patchlist); int patch(Eterm Addresses, Uint fe); static int safe_mul(UWord a, UWord b, UWord* resp); @@ -5389,6 +5392,9 @@ new_literal(LoaderState* stp, Eterm** hpp, Uint heap_size) Eterm erts_module_info_0(Process* p, Eterm module) { + Module* modp; + ErtsCodeIndex code_ix = erts_active_code_ix(); + BeamInstr* code; Eterm *hp; Eterm list = NIL; Eterm tup; @@ -5397,12 +5403,18 @@ erts_module_info_0(Process* p, Eterm module) return THE_NON_VALUE; } - if (erts_get_module(module, erts_active_code_ix()) == NULL) { + modp = erts_get_module(module, code_ix); + if (modp == NULL) { return THE_NON_VALUE; } + code = modp->curr.code; + if (code == NULL) { + return THE_NON_VALUE; + } + #define BUILD_INFO(What) \ - tup = erts_module_info_1(p, module, What); \ + tup = get_module_info(p, code_ix, code, module, What); \ hp = HAlloc(p, 5); \ tup = TUPLE2(hp, What, tup); \ hp += 3; \ @@ -5422,23 +5434,48 @@ erts_module_info_0(Process* p, Eterm module) Eterm erts_module_info_1(Process* p, Eterm module, Eterm what) +{ + Module* modp; + ErtsCodeIndex code_ix = erts_active_code_ix(); + BeamInstr* code; + + if (is_not_atom(module)) { + return THE_NON_VALUE; + } + + modp = erts_get_module(module, code_ix); + if (modp == NULL) { + return THE_NON_VALUE; + } + + code = modp->curr.code; + if (code == NULL) { + return THE_NON_VALUE; + } + + return get_module_info(p, code_ix, code, module, what); +} + +static Eterm +get_module_info(Process* p, ErtsCodeIndex code_ix, BeamInstr* code, + Eterm module, Eterm what) { if (what == am_module) { return module; } else if (what == am_md5) { - return md5_of_module(p, module); + return md5_of_module(p, code); } else if (what == am_exports) { - return exported_from_module(p, module); + return exported_from_module(p, code_ix, module); } else if (what == am_functions) { - return functions_in_module(p, module); + return functions_in_module(p, code); } else if (what == am_attributes) { - return attributes_for_module(p, module); + return attributes_for_module(p, code); } else if (what == am_compile) { - return compilation_info_for_module(p, module); + return compilation_info_for_module(p, code); } else if (what == am_native_addresses) { - return native_addresses(p, module); + return native_addresses(p, code); } else if (what == am_native) { - return has_native(p, module); + return has_native(code); } return THE_NON_VALUE; } @@ -5446,16 +5483,12 @@ erts_module_info_1(Process* p, Eterm module, Eterm what) /* * Builds a list of all functions in the given module: * [{Name, Arity},...] - * - * Returns a tagged term, or 0 on error. */ Eterm functions_in_module(Process* p, /* Process whose heap to use. */ - Eterm mod) /* Tagged atom for module. */ + BeamInstr* code) { - Module* modp; - BeamInstr* code; int i; Uint num_functions; Uint need; @@ -5463,15 +5496,6 @@ functions_in_module(Process* p, /* Process whose heap to use. */ Eterm* hp_end; Eterm result = NIL; - if (is_not_atom(mod)) { - return THE_NON_VALUE; - } - - modp = erts_get_module(mod, erts_active_code_ix()); - if (modp == NULL) { - return THE_NON_VALUE; - } - code = modp->curr.code; num_functions = code[MI_NUM_FUNCTIONS]; need = 5*num_functions; hp = HAlloc(p, need); @@ -5503,23 +5527,12 @@ functions_in_module(Process* p, /* Process whose heap to use. */ */ static Eterm -has_native(Process* p, Eterm mod) +has_native(BeamInstr *code) { Eterm result = am_false; #ifdef HIPE - Module* modp; - - if (is_not_atom(mod)) { - return THE_NON_VALUE; - } - - modp = erts_get_module(mod, erts_active_code_ix()); - if (modp == NULL) { - return THE_NON_VALUE; - } - - if (erts_is_module_native(modp->curr.code)) { - result = am_true; + if (erts_is_module_native(code)) { + result = am_true; } #endif return result; @@ -5548,15 +5561,11 @@ erts_is_module_native(BeamInstr* code) /* * Builds a list of all functions including native addresses. * [{Name,Arity,NativeAddress},...] - * - * Returns a tagged term, or 0 on error. */ static Eterm -native_addresses(Process* p, Eterm mod) +native_addresses(Process* p, BeamInstr* code) { - Module* modp; - BeamInstr* code; int i; Eterm* hp; Uint num_functions; @@ -5564,16 +5573,6 @@ native_addresses(Process* p, Eterm mod) Eterm* hp_end; Eterm result = NIL; - if (is_not_atom(mod)) { - return THE_NON_VALUE; - } - - modp = erts_get_module(mod, erts_active_code_ix()); - if (modp == NULL) { - return THE_NON_VALUE; - } - - code = modp->curr.code; num_functions = code[MI_NUM_FUNCTIONS]; need = (6+BIG_UINT_HEAP_SIZE)*num_functions; hp = HAlloc(p, need); @@ -5600,25 +5599,18 @@ native_addresses(Process* p, Eterm mod) /* * Builds a list of all exported functions in the given module: * [{Name, Arity},...] - * - * Returns a tagged term, or 0 on error. */ Eterm exported_from_module(Process* p, /* Process whose heap to use. */ + ErtsCodeIndex code_ix, Eterm mod) /* Tagged atom for module. */ { int i; Eterm* hp = NULL; Eterm* hend = NULL; Eterm result = NIL; - ErtsCodeIndex code_ix; - - if (is_not_atom(mod)) { - return THE_NON_VALUE; - } - code_ix = erts_active_code_ix(); for (i = 0; i < export_list_size(code_ix); i++) { Export* ep = export_list(i,code_ix); @@ -5648,31 +5640,17 @@ exported_from_module(Process* p, /* Process whose heap to use. */ /* * Returns a list of all attributes for the module. - * - * Returns a tagged term, or 0 on error. */ Eterm attributes_for_module(Process* p, /* Process whose heap to use. */ - Eterm mod) /* Tagged atom for module. */ - + BeamInstr* code) { - Module* modp; - BeamInstr* code; Eterm* hp; byte* ext; Eterm result = NIL; Eterm* end; - if (is_not_atom(mod)) { - return THE_NON_VALUE; - } - - modp = erts_get_module(mod, erts_active_code_ix()); - if (modp == NULL) { - return THE_NON_VALUE; - } - code = modp->curr.code; ext = (byte *) code[MI_ATTR_PTR]; if (ext != NULL) { hp = HAlloc(p, code[MI_ATTR_SIZE_ON_HEAP]); @@ -5688,30 +5666,17 @@ attributes_for_module(Process* p, /* Process whose heap to use. */ /* * Returns a list containing compilation information. - * - * Returns a tagged term, or 0 on error. */ Eterm compilation_info_for_module(Process* p, /* Process whose heap to use. */ - Eterm mod) /* Tagged atom for module. */ + BeamInstr* code) { - Module* modp; - BeamInstr* code; Eterm* hp; byte* ext; Eterm result = NIL; Eterm* end; - if (is_not_atom(mod)) { - return THE_NON_VALUE; - } - - modp = erts_get_module(mod, erts_active_code_ix()); - if (modp == NULL) { - return THE_NON_VALUE; - } - code = modp->curr.code; ext = (byte *) code[MI_COMPILE_PTR]; if (ext != NULL) { hp = HAlloc(p, code[MI_COMPILE_SIZE_ON_HEAP]); @@ -5727,33 +5692,13 @@ compilation_info_for_module(Process* p, /* Process whose heap to use. */ /* * Returns the MD5 checksum for a module - * - * Returns a tagged term, or 0 on error. */ Eterm md5_of_module(Process* p, /* Process whose heap to use. */ - Eterm mod) /* Tagged atom for module. */ + BeamInstr* code) { - Module* modp; - BeamInstr* code; - Eterm res = NIL; - - if (is_not_atom(mod)) { - return THE_NON_VALUE; - } - - modp = erts_get_module(mod, erts_active_code_ix()); - if (modp == NULL) { - return THE_NON_VALUE; - } - code = modp->curr.code; - if (code[MI_MD5_PTR] != 0) { - res = new_binary(p, (byte *) code[MI_MD5_PTR], MD5_SIZE); - } else { - res = am_undefined; - } - return res; + return new_binary(p, (byte *) code[MI_MD5_PTR], MD5_SIZE); } /* -- cgit v1.2.3