From 6aa29abe9fab81e153d6232edf4ba048ac7d0b6e Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Mon, 22 May 2000 16:33:19 +0000 Subject: Update. 2000-05-21 H.J. Lu * elf/do-lookup.h (do_lookup_versioned): Replace reloc_type parameter with noexec and noplt parameter. (do_lookup): Likewise. * elf/dl-lookup.c (_dl_lookup_symbol): Change for new parameters of do_lookup. Support STV_PROTECTED. (_dl_lookup_symbol_skip): Likewise. (_dl_lookup_versioned_symbol): Likewise. (_dl_lookup_versioned_symbol_skip): Likewise. * elf/dl-reloc.c (RESOLVE): Check STB_LOCAL instead of ST_VISIBILITY. * elf/dl-runtime.c (profile_fixup): Fix a typo in comment. --- elf/dl-lookup.c | 161 +++++++++++++++++++++++++++++++++++++++++++++++-------- elf/dl-reloc.c | 2 +- elf/dl-runtime.c | 2 +- 3 files changed, 142 insertions(+), 23 deletions(-) (limited to 'elf') diff --git a/elf/dl-lookup.c b/elf/dl-lookup.c index c4eb8a6..09f34f9 100644 --- a/elf/dl-lookup.c +++ b/elf/dl-lookup.c @@ -75,9 +75,11 @@ __libc_lock_define (extern, _dl_load_lock) without versioning. gcc is not able to optimize a single function definition serving for both purposes so we define two functions. */ #define VERSIONED 0 +#define PROTECTED 0 #include "do-lookup.h" #define VERSIONED 1 +#define PROTECTED 0 #include "do-lookup.h" @@ -194,13 +196,16 @@ _dl_lookup_symbol (const char *undef_name, struct link_map *undef_map, const unsigned long int hash = _dl_elf_hash (undef_name); struct sym_val current_value = { NULL, NULL }; struct r_scope_elem **scope; + int protected; + int noexec = elf_machine_lookup_noexec_p (reloc_type); + int noplt = elf_machine_lookup_noplt_p (reloc_type); ++_dl_num_relocations; /* Search the relevant loaded objects for a definition. */ for (scope = symbol_scope; *scope; ++scope) if (do_lookup (undef_name, undef_map, hash, *ref, ¤t_value, - *scope, 0, NULL, reloc_type)) + *scope, 0, NULL, noexec, noplt)) { /* We have to check whether this would bind UNDEF_MAP to an object in the global scope which was dynamically loaded. In this case @@ -232,6 +237,8 @@ _dl_lookup_symbol (const char *undef_name, struct link_map *undef_map, return 0; } + protected = *ref && ELFW(ST_VISIBILITY) ((*ref)->st_other) == STV_PROTECTED; + if (__builtin_expect (_dl_debug_bindings, 0)) _dl_debug_message (1, "binding file ", (reference_name && reference_name[0] @@ -239,10 +246,33 @@ _dl_lookup_symbol (const char *undef_name, struct link_map *undef_map, : (_dl_argv[0] ?: "
")), " to ", current_value.m->l_name[0] ? current_value.m->l_name : _dl_argv[0], - ": symbol `", undef_name, "'\n", NULL); + ": ", protected ? "protected" : "normal", + " symbol `", undef_name, "'\n", NULL); + + if (__builtin_expect (protected == 0, 1)) + { + *ref = current_value.s; + return LOOKUP_VALUE (current_value.m); + } + else + { + /* It is very tricky. We need to figure out what value to + return for the protected symbol */ + struct sym_val protected_value = { NULL, NULL }; + + for (scope = symbol_scope; *scope; ++scope) + if (do_lookup (undef_name, undef_map, hash, *ref, + &protected_value, *scope, 0, NULL, 0, 1)) + break; + + if (protected_value.s == NULL || protected_value.m == undef_map) + { + *ref = current_value.s; + return LOOKUP_VALUE (current_value.m); + } - *ref = current_value.s; - return LOOKUP_VALUE (current_value.m); + return LOOKUP_VALUE (undef_map); + } } @@ -263,6 +293,7 @@ _dl_lookup_symbol_skip (const char *undef_name, struct sym_val current_value = { NULL, NULL }; struct r_scope_elem **scope; size_t i; + int protected; ++_dl_num_relocations; @@ -273,7 +304,7 @@ _dl_lookup_symbol_skip (const char *undef_name, if (i < (*scope)->r_nlist && do_lookup (undef_name, undef_map, hash, *ref, ¤t_value, - *scope, i, skip_map, 0)) + *scope, i, skip_map, 0, 0)) { /* We have to check whether this would bind UNDEF_MAP to an object in the global scope which was dynamically loaded. In this case @@ -293,7 +324,7 @@ _dl_lookup_symbol_skip (const char *undef_name, else while (*++scope) if (do_lookup (undef_name, undef_map, hash, *ref, ¤t_value, - *scope, 0, skip_map, 0)) + *scope, 0, skip_map, 0, 0)) { /* We have to check whether this would bind UNDEF_MAP to an object in the global scope which was dynamically loaded. In this case @@ -319,6 +350,8 @@ _dl_lookup_symbol_skip (const char *undef_name, return 0; } + protected = *ref && ELFW(ST_VISIBILITY) ((*ref)->st_other) == STV_PROTECTED; + if (__builtin_expect (_dl_debug_bindings, 0)) _dl_debug_message (1, "binding file ", (reference_name && reference_name[0] @@ -326,10 +359,36 @@ _dl_lookup_symbol_skip (const char *undef_name, : (_dl_argv[0] ?: "
")), " to ", current_value.m->l_name[0] ? current_value.m->l_name : _dl_argv[0], - ": symbol `", undef_name, "' (skip)\n", NULL); + ": ", protected ? "protected" : "normal", + " symbol `", undef_name, "'\n", NULL); - *ref = current_value.s; - return LOOKUP_VALUE (current_value.m); + if (__builtin_expect (protected == 0, 1)) + { + *ref = current_value.s; + return LOOKUP_VALUE (current_value.m); + } + else + { + /* It is very tricky. We need to figure out what value to + return for the protected symbol */ + struct sym_val protected_value = { NULL, NULL }; + + if (i >= (*scope)->r_nlist + || !do_lookup (undef_name, undef_map, hash, *ref, &protected_value, + *scope, i, skip_map, 0, 1)) + while (*++scope) + if (do_lookup (undef_name, undef_map, hash, *ref, &protected_value, + *scope, 0, skip_map, 0, 1)) + break; + + if (protected_value.s == NULL || protected_value.m == undef_map) + { + *ref = current_value.s; + return LOOKUP_VALUE (current_value.m); + } + + return LOOKUP_VALUE (undef_map); + } } @@ -350,6 +409,9 @@ _dl_lookup_versioned_symbol (const char *undef_name, const unsigned long int hash = _dl_elf_hash (undef_name); struct sym_val current_value = { NULL, NULL }; struct r_scope_elem **scope; + int protected; + int noexec = elf_machine_lookup_noexec_p (reloc_type); + int noplt = elf_machine_lookup_noplt_p (reloc_type); ++_dl_num_relocations; @@ -358,7 +420,7 @@ _dl_lookup_versioned_symbol (const char *undef_name, { int res = do_lookup_versioned (undef_name, undef_map, hash, *ref, ¤t_value, *scope, 0, version, NULL, - reloc_type); + noexec, noplt); if (res > 0) { /* We have to check whether this would bind UNDEF_MAP to an object @@ -412,6 +474,8 @@ _dl_lookup_versioned_symbol (const char *undef_name, return 0; } + protected = *ref && ELFW(ST_VISIBILITY) ((*ref)->st_other) == STV_PROTECTED; + if (__builtin_expect (_dl_debug_bindings, 0)) _dl_debug_message (1, "binding file ", (reference_name && reference_name[0] @@ -419,11 +483,35 @@ _dl_lookup_versioned_symbol (const char *undef_name, : (_dl_argv[0] ?: "
")), " to ", current_value.m->l_name[0] ? current_value.m->l_name : _dl_argv[0], - ": symbol `", undef_name, "' [", version->name, + ": ", protected ? "protected" : "normal", + " symbol `", undef_name, "' [", version->name, "]\n", NULL); - *ref = current_value.s; - return LOOKUP_VALUE (current_value.m); + if (__builtin_expect (protected == 0, 1)) + { + *ref = current_value.s; + return LOOKUP_VALUE (current_value.m); + } + else + { + /* It is very tricky. We need to figure out what value to + return for the protected symbol */ + struct sym_val protected_value = { NULL, NULL }; + + for (scope = symbol_scope; *scope; ++scope) + if (do_lookup_versioned (undef_name, undef_map, hash, *ref, + &protected_value, *scope, 0, version, NULL, + 0, 1)) + break; + + if (protected_value.s == NULL || protected_value.m == undef_map) + { + *ref = current_value.s; + return LOOKUP_VALUE (current_value.m); + } + + return LOOKUP_VALUE (undef_map); + } } @@ -443,6 +531,7 @@ _dl_lookup_versioned_symbol_skip (const char *undef_name, struct sym_val current_value = { NULL, NULL }; struct r_scope_elem **scope; size_t i; + int protected; ++_dl_num_relocations; @@ -453,7 +542,8 @@ _dl_lookup_versioned_symbol_skip (const char *undef_name, if (i < (*scope)->r_nlist && do_lookup_versioned (undef_name, undef_map, hash, *ref, - ¤t_value, *scope, i, version, skip_map, 0)) + ¤t_value, *scope, i, version, skip_map, + 0, 0)) { /* We have to check whether this would bind UNDEF_MAP to an object in the global scope which was dynamically loaded. In this case @@ -475,7 +565,7 @@ _dl_lookup_versioned_symbol_skip (const char *undef_name, while (*++scope) if (do_lookup_versioned (undef_name, undef_map, hash, *ref, ¤t_value, *scope, 0, version, skip_map, - 0)) + 0, 0)) { /* We have to check whether this would bind UNDEF_MAP to an object in the global scope which was dynamically loaded. In this case @@ -512,19 +602,48 @@ _dl_lookup_versioned_symbol_skip (const char *undef_name, return 0; } + protected = *ref && ELFW(ST_VISIBILITY) ((*ref)->st_other) == STV_PROTECTED; + if (__builtin_expect (_dl_debug_bindings, 0)) _dl_debug_message (1, "binding file ", (reference_name && reference_name[0] ? reference_name : (_dl_argv[0] ?: "
")), - " to ", - current_value.m->l_name[0] + " to ", current_value.m->l_name[0] ? current_value.m->l_name : _dl_argv[0], - ": symbol `", undef_name, "' [", version->name, - "] (skip)\n", NULL); + ": ", protected ? "protected" : "normal", + " symbol `", undef_name, "' [", version->name, + "]\n", NULL); + + if (__builtin_expect (protected == 0, 1)) + { + *ref = current_value.s; + return LOOKUP_VALUE (current_value.m); + } + else + { + /* It is very tricky. We need to figure out what value to + return for the protected symbol */ + struct sym_val protected_value = { NULL, NULL }; + + if (i >= (*scope)->r_nlist + || !do_lookup_versioned (undef_name, undef_map, hash, *ref, + &protected_value, *scope, i, version, + skip_map, 0, 1)) + while (*++scope) + if (do_lookup_versioned (undef_name, undef_map, hash, *ref, + &protected_value, *scope, 0, version, + skip_map, 0, 1)) + break; + + if (protected_value.s == NULL || protected_value.m == undef_map) + { + *ref = current_value.s; + return LOOKUP_VALUE (current_value.m); + } - *ref = current_value.s; - return LOOKUP_VALUE (current_value.m); + return LOOKUP_VALUE (undef_map); + } } diff --git a/elf/dl-reloc.c b/elf/dl-reloc.c index 3bfba77..50bc8e8 100644 --- a/elf/dl-reloc.c +++ b/elf/dl-reloc.c @@ -79,7 +79,7 @@ _dl_relocate_object (struct link_map *l, struct r_scope_elem *scope[], (flags))) \ : l) #define RESOLVE(ref, version, flags) \ - (__builtin_expect (ELFW(ST_VISIBILITY) ((*ref)->st_other), 0) == 0 \ + (ELFW(ST_BIND) ((*ref)->st_info) != STB_LOCAL \ ? ((version) != NULL && (version)->hash != 0 \ ? _dl_lookup_versioned_symbol (strtab + (*ref)->st_name, l, (ref), \ scope, (version), (flags)) \ diff --git a/elf/dl-runtime.c b/elf/dl-runtime.c index 6237afc..f0635ea 100644 --- a/elf/dl-runtime.c +++ b/elf/dl-runtime.c @@ -158,7 +158,7 @@ profile_fixup ( /* Sanity check that we're really looking at a PLT relocation. */ assert (ELFW(R_TYPE)(reloc->r_info) == ELF_MACHINE_JMP_SLOT); - /* Look up the target symbol. If the symbol is marked STV_PROTEXTED + /* Look up the target symbol. If the symbol is marked STV_PROTECTED don't look in the global scope. */ if (__builtin_expect (ELFW(ST_VISIBILITY) (sym->st_other), 0) == 0) { -- cgit v1.1