From 0ecb606cb6cf65de1d9fc8a919bceb4be476c602 Mon Sep 17 00:00:00 2001 From: Jakub Jelinek Date: Thu, 12 Jul 2007 18:26:36 +0000 Subject: 2.5-18.1 --- elf/dl-addr.c | 193 ++++++++++++++++++++++++++++++++++------------------------ 1 file changed, 114 insertions(+), 79 deletions(-) (limited to 'elf/dl-addr.c') diff --git a/elf/dl-addr.c b/elf/dl-addr.c index 685cab9be8..7dbf716cfa 100644 --- a/elf/dl-addr.c +++ b/elf/dl-addr.c @@ -1,5 +1,5 @@ /* Locate the shared object symbol nearest a given address. - Copyright (C) 1996-2003, 2004 Free Software Foundation, Inc. + Copyright (C) 1996-2004, 2005, 2006, 2007 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or @@ -22,61 +22,62 @@ #include -int -internal_function -_dl_addr (const void *address, Dl_info *info, - struct link_map **mapp, const ElfW(Sym) **symbolp) +static void +__attribute ((always_inline)) +determine_info (const ElfW(Addr) addr, struct link_map *match, Dl_info *info, + struct link_map **mapp, const ElfW(Sym) **symbolp) { - const ElfW(Addr) addr = DL_LOOKUP_ADDRESS (address); - struct link_map *match; - const ElfW(Sym) *symtab, *matchsym, *symtabend; - const char *strtab; - ElfW(Word) strtabsize; + /* Now we know what object the address lies in. */ + info->dli_fname = match->l_name; + info->dli_fbase = (void *) match->l_map_start; - /* Protect against concurrent loads and unloads. */ - __rtld_lock_lock_recursive (GL(dl_load_lock)); + /* If this is the main program the information is incomplete. */ + if (__builtin_expect (match->l_name[0], 'a') == '\0' + && match->l_type == lt_executable) + info->dli_fname = _dl_argv[0]; - /* Find the highest-addressed object that ADDRESS is not below. */ - match = NULL; - for (Lmid_t ns = 0; ns < DL_NNS; ++ns) - for (struct link_map *l = GL(dl_ns)[ns]._ns_loaded; l; l = l->l_next) - if (addr >= l->l_map_start && addr < l->l_map_end) + const ElfW(Sym) *symtab + = (const ElfW(Sym) *) D_PTR (match, l_info[DT_SYMTAB]); + const char *strtab = (const char *) D_PTR (match, l_info[DT_STRTAB]); + + ElfW(Word) strtabsize = match->l_info[DT_STRSZ]->d_un.d_val; + + const ElfW(Sym) *matchsym = NULL; + if (match->l_info[DT_ADDRTAGIDX (DT_GNU_HASH) + DT_NUM + DT_THISPROCNUM + + DT_VERSIONTAGNUM + DT_EXTRANUM + DT_VALNUM] != NULL) + { + /* We look at all symbol table entries referenced by the hash + table. */ + for (Elf_Symndx bucket = 0; bucket < match->l_nbuckets; ++bucket) { - /* We know ADDRESS lies within L if in any shared object. - Make sure it isn't past the end of L's segments. */ - size_t n = l->l_phnum; - if (n > 0) + Elf32_Word symndx = match->l_gnu_buckets[bucket]; + if (symndx != 0) { + const Elf32_Word *hasharr = &match->l_gnu_chain_zero[symndx]; + do - --n; - while (l->l_phdr[n].p_type != PT_LOAD); - if (addr >= (l->l_addr + - l->l_phdr[n].p_vaddr + l->l_phdr[n].p_memsz)) - /* Off the end of the highest-addressed shared object. */ - continue; + { + /* The hash table never references local symbols so + we can omit that test here. */ + if ((symtab[symndx].st_shndx != SHN_UNDEF + || symtab[symndx].st_value != 0) +#ifdef USE_TLS + && ELFW(ST_TYPE) (symtab[symndx].st_info) != STT_TLS +#endif + && DL_ADDR_SYM_MATCH (match, &symtab[symndx], + matchsym, addr) + && symtab[symndx].st_name < strtabsize) + matchsym = (ElfW(Sym) *) &symtab[symndx]; + + ++symndx; + } + while ((*hasharr++ & 1u) == 0); } - - match = l; - break; } - - int result = 0; - if (match != NULL) + } + else { - /* Now we know what object the address lies in. */ - info->dli_fname = match->l_name; - info->dli_fbase = (void *) match->l_map_start; - - /* If this is the main program the information is incomplete. */ - if (__builtin_expect (match->l_name[0], 'a') == '\0' - && match->l_type == lt_executable) - info->dli_fname = _dl_argv[0]; - - symtab = (const void *) D_PTR (match, l_info[DT_SYMTAB]); - strtab = (const void *) D_PTR (match, l_info[DT_STRTAB]); - - strtabsize = match->l_info[DT_STRSZ]->d_un.d_val; - + const ElfW(Sym) *symtabend; if (match->l_info[DT_HASH] != NULL) symtabend = (symtab + ((Elf_Symndx *) D_PTR (match, l_info[DT_HASH]))[1]); @@ -87,49 +88,83 @@ _dl_addr (const void *address, Dl_info *info, the string table which generally follows the symbol table. */ symtabend = (const ElfW(Sym) *) strtab; - /* We assume that the string table follows the symbol table, - because there is no way in ELF to know the size of the - dynamic symbol table!! */ - for (matchsym = NULL; (void *) symtab < (void *) symtabend; ++symtab) - if (addr >= match->l_addr + symtab->st_value -#if defined USE_TLS + for (; (void *) symtab < (void *) symtabend; ++symtab) + if ((ELFW(ST_BIND) (symtab->st_info) == STB_GLOBAL + || ELFW(ST_BIND) (symtab->st_info) == STB_WEAK) +#ifdef USE_TLS && ELFW(ST_TYPE) (symtab->st_info) != STT_TLS #endif - && ((symtab->st_size == 0 - && addr == match->l_addr + symtab->st_value) - || addr < match->l_addr + symtab->st_value + symtab->st_size) - && symtab->st_name < strtabsize - && (matchsym == NULL || matchsym->st_value < symtab->st_value) - && (ELFW(ST_BIND) (symtab->st_info) == STB_GLOBAL - || ELFW(ST_BIND) (symtab->st_info) == STB_WEAK)) + && (symtab->st_shndx != SHN_UNDEF + || symtab->st_value != 0) + && DL_ADDR_SYM_MATCH (match, symtab, matchsym, addr) + && symtab->st_name < strtabsize) matchsym = (ElfW(Sym) *) symtab; + } - if (mapp) - *mapp = match; - if (symbolp) - *symbolp = matchsym; + if (mapp) + *mapp = match; + if (symbolp) + *symbolp = matchsym; - if (matchsym) - { - /* We found a symbol close by. Fill in its name and exact - address. */ - lookup_t matchl = LOOKUP_VALUE (match); + if (matchsym) + { + /* We found a symbol close by. Fill in its name and exact + address. */ + lookup_t matchl = LOOKUP_VALUE (match); - info->dli_sname = strtab + matchsym->st_name; - info->dli_saddr = DL_SYMBOL_ADDRESS (matchl, matchsym); - } - else + info->dli_sname = strtab + matchsym->st_name; + info->dli_saddr = DL_SYMBOL_ADDRESS (matchl, matchsym); + } + else + { + /* No symbol matches. We return only the containing object. */ + info->dli_sname = NULL; + info->dli_saddr = NULL; + } +} + + +int +internal_function +_dl_addr (const void *address, Dl_info *info, + struct link_map **mapp, const ElfW(Sym) **symbolp) +{ + const ElfW(Addr) addr = DL_LOOKUP_ADDRESS (address); + int result = 0; + + /* Protect against concurrent loads and unloads. */ + __rtld_lock_lock_recursive (GL(dl_load_lock)); + + /* Find the highest-addressed object that ADDRESS is not below. */ + for (Lmid_t ns = 0; ns < DL_NNS; ++ns) + for (struct link_map *l = GL(dl_ns)[ns]._ns_loaded; l; l = l->l_next) + if (addr >= l->l_map_start && addr < l->l_map_end + && (l->l_contiguous || _dl_addr_inside_object (l, addr))) { - /* No symbol matches. We return only the containing object. */ - info->dli_sname = NULL; - info->dli_saddr = NULL; + determine_info (addr, l, info, mapp, symbolp); + result = 1; + goto out; } - result = 1; - } - + out: __rtld_lock_unlock_recursive (GL(dl_load_lock)); return result; } libc_hidden_def (_dl_addr) + +/* Return non-zero if ADDR lies within one of L's segments. */ +int +internal_function +_dl_addr_inside_object (struct link_map *l, const ElfW(Addr) addr) +{ + int n = l->l_phnum; + const ElfW(Addr) reladdr = addr - l->l_addr; + + while (--n >= 0) + if (l->l_phdr[n].p_type == PT_LOAD + && reladdr - l->l_phdr[n].p_vaddr >= 0 + && reladdr - l->l_phdr[n].p_vaddr < l->l_phdr[n].p_memsz) + return 1; + return 0; +} -- cgit v1.2.3