diff options
Diffstat (limited to 'elf')
| -rw-r--r-- | elf/dl-brk.c | 5 | ||||
| -rw-r--r-- | elf/dl-cache.c | 311 | ||||
| -rw-r--r-- | elf/dl-environ.c | 86 | ||||
| -rw-r--r-- | elf/dl-execstack.c | 32 | ||||
| -rw-r--r-- | elf/dl-fptr.c | 323 | ||||
| -rw-r--r-- | elf/dl-origin.c | 51 | ||||
| -rw-r--r-- | elf/dl-sbrk.c | 5 | ||||
| -rw-r--r-- | elf/dl-symaddr.c | 33 | ||||
| -rw-r--r-- | elf/dl-sysdep.c | 590 | ||||
| -rw-r--r-- | elf/dl-tls.c | 799 | ||||
| -rw-r--r-- | elf/dl-trampoline.c | 1 |
11 files changed, 2236 insertions, 0 deletions
diff --git a/elf/dl-brk.c b/elf/dl-brk.c new file mode 100644 index 0000000000..c37cdfec33 --- /dev/null +++ b/elf/dl-brk.c @@ -0,0 +1,5 @@ +/* We can use the normal code but we also know the __curbrk is not exported + from ld.so. */ +extern void *__curbrk attribute_hidden; + +#include <brk.c> diff --git a/elf/dl-cache.c b/elf/dl-cache.c new file mode 100644 index 0000000000..29886e194a --- /dev/null +++ b/elf/dl-cache.c @@ -0,0 +1,311 @@ +/* Support for reading /etc/ld.so.cache files written by Linux ldconfig. + Copyright (C) 1996-2002, 2003, 2004 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 + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <assert.h> +#include <unistd.h> +#include <ldsodefs.h> +#include <sys/mman.h> +#include <dl-cache.h> +#include <dl-procinfo.h> + +#include <stdio-common/_itoa.h> + +#ifndef _DL_PLATFORMS_COUNT +# define _DL_PLATFORMS_COUNT 0 +#endif + +/* This is the starting address and the size of the mmap()ed file. */ +static struct cache_file *cache; +static struct cache_file_new *cache_new; +static size_t cachesize; + +/* 1 if cache_data + PTR points into the cache. */ +#define _dl_cache_verify_ptr(ptr) (ptr < cache_data_size) + +#define SEARCH_CACHE(cache) \ +/* We use binary search since the table is sorted in the cache file. \ + The first matching entry in the table is returned. \ + It is important to use the same algorithm as used while generating \ + the cache file. */ \ +do \ + { \ + left = 0; \ + right = cache->nlibs - 1; \ + \ + while (left <= right) \ + { \ + __typeof__ (cache->libs[0].key) key; \ + \ + middle = (left + right) / 2; \ + \ + key = cache->libs[middle].key; \ + \ + /* Make sure string table indices are not bogus before using \ + them. */ \ + if (! _dl_cache_verify_ptr (key)) \ + { \ + cmpres = 1; \ + break; \ + } \ + \ + /* Actually compare the entry with the key. */ \ + cmpres = _dl_cache_libcmp (name, cache_data + key); \ + if (__builtin_expect (cmpres == 0, 0)) \ + { \ + /* Found it. LEFT now marks the last entry for which we \ + know the name is correct. */ \ + left = middle; \ + \ + /* There might be entries with this name before the one we \ + found. So we have to find the beginning. */ \ + while (middle > 0) \ + { \ + __typeof__ (cache->libs[0].key) key; \ + \ + key = cache->libs[middle - 1].key; \ + /* Make sure string table indices are not bogus before \ + using them. */ \ + if (! _dl_cache_verify_ptr (key) \ + /* Actually compare the entry. */ \ + || _dl_cache_libcmp (name, cache_data + key) != 0) \ + break; \ + --middle; \ + } \ + \ + do \ + { \ + int flags; \ + __typeof__ (cache->libs[0]) *lib = &cache->libs[middle]; \ + \ + /* Only perform the name test if necessary. */ \ + if (middle > left \ + /* We haven't seen this string so far. Test whether the \ + index is ok and whether the name matches. Otherwise \ + we are done. */ \ + && (! _dl_cache_verify_ptr (lib->key) \ + || (_dl_cache_libcmp (name, cache_data + lib->key) \ + != 0))) \ + break; \ + \ + flags = lib->flags; \ + if (_dl_cache_check_flags (flags) \ + && _dl_cache_verify_ptr (lib->value)) \ + { \ + if (best == NULL || flags == GLRO(dl_correct_cache_id)) \ + { \ + HWCAP_CHECK; \ + best = cache_data + lib->value; \ + \ + if (flags == GLRO(dl_correct_cache_id)) \ + /* We've found an exact match for the shared \ + object and no general `ELF' release. Stop \ + searching. */ \ + break; \ + } \ + } \ + } \ + while (++middle <= right); \ + break; \ + } \ + \ + if (cmpres < 0) \ + left = middle + 1; \ + else \ + right = middle - 1; \ + } \ + } \ +while (0) + + +int +internal_function +_dl_cache_libcmp (const char *p1, const char *p2) +{ + while (*p1 != '\0') + { + if (*p1 >= '0' && *p1 <= '9') + { + if (*p2 >= '0' && *p2 <= '9') + { + /* Must compare this numerically. */ + int val1; + int val2; + + val1 = *p1++ - '0'; + val2 = *p2++ - '0'; + while (*p1 >= '0' && *p1 <= '9') + val1 = val1 * 10 + *p1++ - '0'; + while (*p2 >= '0' && *p2 <= '9') + val2 = val2 * 10 + *p2++ - '0'; + if (val1 != val2) + return val1 - val2; + } + else + return 1; + } + else if (*p2 >= '0' && *p2 <= '9') + return -1; + else if (*p1 != *p2) + return *p1 - *p2; + else + { + ++p1; + ++p2; + } + } + return *p1 - *p2; +} + + +/* Look up NAME in ld.so.cache and return the file name stored there, + or null if none is found. */ + +const char * +internal_function +_dl_load_cache_lookup (const char *name) +{ + int left, right, middle; + int cmpres; + const char *cache_data; + uint32_t cache_data_size; + const char *best; + + /* Print a message if the loading of libs is traced. */ + if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_LIBS, 0)) + _dl_debug_printf (" search cache=%s\n", LD_SO_CACHE); + + if (cache == NULL) + { + /* Read the contents of the file. */ + void *file = _dl_sysdep_read_whole_file (LD_SO_CACHE, &cachesize, + PROT_READ); + + /* We can handle three different cache file formats here: + - the old libc5/glibc2.0/2.1 format + - the old format with the new format in it + - only the new format + The following checks if the cache contains any of these formats. */ + if (file != MAP_FAILED && cachesize > sizeof *cache + && memcmp (file, CACHEMAGIC, sizeof CACHEMAGIC - 1) == 0) + { + size_t offset; + /* Looks ok. */ + cache = file; + + /* Check for new version. */ + offset = ALIGN_CACHE (sizeof (struct cache_file) + + cache->nlibs * sizeof (struct file_entry)); + + cache_new = (struct cache_file_new *) ((void *) cache + offset); + if (cachesize < (offset + sizeof (struct cache_file_new)) + || memcmp (cache_new->magic, CACHEMAGIC_VERSION_NEW, + sizeof CACHEMAGIC_VERSION_NEW - 1) != 0) + cache_new = (void *) -1; + } + else if (file != MAP_FAILED && cachesize > sizeof *cache_new + && memcmp (file, CACHEMAGIC_VERSION_NEW, + sizeof CACHEMAGIC_VERSION_NEW - 1) == 0) + { + cache_new = file; + cache = file; + } + else + { + if (file != MAP_FAILED) + __munmap (file, cachesize); + cache = (void *) -1; + } + + assert (cache != NULL); + } + + if (cache == (void *) -1) + /* Previously looked for the cache file and didn't find it. */ + return NULL; + + best = NULL; + + if (cache_new != (void *) -1) + { + uint64_t platform; + + /* This is where the strings start. */ + cache_data = (const char *) cache_new; + + /* Now we can compute how large the string table is. */ + cache_data_size = (const char *) cache + cachesize - cache_data; + + platform = _dl_string_platform (GLRO(dl_platform)); + if (platform != (uint64_t) -1) + platform = 1ULL << platform; + + /* Only accept hwcap if it's for the right platform. */ +#ifdef USE_TLS +# define _DL_HWCAP_TLS_MASK (1LL << 63) +#else +# define _DL_HWCAP_TLS_MASK 0 +#endif +#define HWCAP_CHECK \ + if (GLRO(dl_osversion) && lib->osversion > GLRO(dl_osversion)) \ + continue; \ + if (_DL_PLATFORMS_COUNT && platform != -1 \ + && (lib->hwcap & _DL_HWCAP_PLATFORM) != 0 \ + && (lib->hwcap & _DL_HWCAP_PLATFORM) != platform) \ + continue; \ + if (lib->hwcap \ + & ~(GLRO(dl_hwcap) | _DL_HWCAP_PLATFORM | _DL_HWCAP_TLS_MASK)) \ + continue + SEARCH_CACHE (cache_new); + } + else + { + /* This is where the strings start. */ + cache_data = (const char *) &cache->libs[cache->nlibs]; + + /* Now we can compute how large the string table is. */ + cache_data_size = (const char *) cache + cachesize - cache_data; + +#undef HWCAP_CHECK +#define HWCAP_CHECK do {} while (0) + SEARCH_CACHE (cache); + } + + /* Print our result if wanted. */ + if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_LIBS, 0) + && best != NULL) + _dl_debug_printf (" trying file=%s\n", best); + + return best; +} + +#ifndef MAP_COPY +/* If the system does not support MAP_COPY we cannot leave the file open + all the time since this would create problems when the file is replaced. + Therefore we provide this function to close the file and open it again + once needed. */ +void +_dl_unload_cache (void) +{ + if (cache != NULL && cache != (struct cache_file *) -1) + { + __munmap (cache, cachesize); + cache = NULL; + } +} +#endif diff --git a/elf/dl-environ.c b/elf/dl-environ.c new file mode 100644 index 0000000000..089e89e6e7 --- /dev/null +++ b/elf/dl-environ.c @@ -0,0 +1,86 @@ +/* Environment handling for dynamic loader. + Copyright (C) 1995-1998, 2000, 2001, 2002 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 + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <string.h> +#include <stdlib.h> +#include <unistd.h> +#include <ldsodefs.h> + +/* Walk through the environment of the process and return all entries + starting with `LD_'. */ +char * +internal_function +_dl_next_ld_env_entry (char ***position) +{ + char **current = *position; + char *result = NULL; + + while (*current != NULL) + { + if (__builtin_expect ((*current)[0] == 'L', 0) + && (*current)[1] == 'D' && (*current)[2] == '_') + { + result = &(*current)[3]; + + /* Save current position for next visit. */ + *position = ++current; + + break; + } + + ++current; + } + + return result; +} + + +/* In ld.so __environ is not exported. */ +extern char **__environ attribute_hidden; + +int +unsetenv (const char *name) +{ + char **ep; + + ep = __environ; + while (*ep != NULL) + { + size_t cnt = 0; + + while ((*ep)[cnt] == name[cnt] && name[cnt] != '\0') + ++cnt; + + if (name[cnt] == '\0' && (*ep)[cnt] == '=') + { + /* Found it. Remove this pointer by moving later ones to + the front. */ + char **dp = ep; + + do + dp[0] = dp[1]; + while (*dp++); + /* Continue the loop in case NAME appears again. */ + } + else + ++ep; + } + + return 0; +} diff --git a/elf/dl-execstack.c b/elf/dl-execstack.c new file mode 100644 index 0000000000..6dce21e7a1 --- /dev/null +++ b/elf/dl-execstack.c @@ -0,0 +1,32 @@ +/* Stack executability handling for GNU dynamic linker. Stub version. + Copyright (C) 2003, 2004 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 + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <ldsodefs.h> +#include <errno.h> + +/* There is no portable way to know the bounds of the initial thread's stack + so as to mprotect it. */ + +int +internal_function +_dl_make_stack_executable (void **stack_endp) +{ + return ENOSYS; +} +rtld_hidden_def (_dl_make_stack_executable) diff --git a/elf/dl-fptr.c b/elf/dl-fptr.c new file mode 100644 index 0000000000..78beecfdcb --- /dev/null +++ b/elf/dl-fptr.c @@ -0,0 +1,323 @@ +/* Manage function descriptors. Generic version. + Copyright (C) 1999,2000,2001,2002,2003,2004 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 + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <libintl.h> +#include <unistd.h> +#include <string.h> +#include <sys/param.h> +#include <sys/mman.h> +#include <link.h> +#include <ldsodefs.h> +#include <elf/dynamic-link.h> +#include <dl-fptr.h> +#include <atomic.h> + +#ifndef ELF_MACHINE_BOOT_FPTR_TABLE_LEN +/* ELF_MACHINE_BOOT_FPTR_TABLE_LEN should be greater than the number of + dynamic symbols in ld.so. */ +# define ELF_MACHINE_BOOT_FPTR_TABLE_LEN 256 +#endif + +#ifndef ELF_MACHINE_LOAD_ADDRESS +# error "ELF_MACHINE_LOAD_ADDRESS is not defined." +#endif + +#ifndef COMPARE_AND_SWAP +# define COMPARE_AND_SWAP(ptr, old, new) \ + (atomic_compare_and_exchange_bool_acq (ptr, new, old) == 0) +#endif + +ElfW(Addr) _dl_boot_fptr_table [ELF_MACHINE_BOOT_FPTR_TABLE_LEN]; + +static struct local + { + struct fdesc_table *root; + struct fdesc *free_list; + unsigned int npages; /* # of pages to allocate */ + /* the next to members MUST be consecutive! */ + struct fdesc_table boot_table; + struct fdesc boot_fdescs[1024]; + } +local = + { + .root = &local.boot_table, + .npages = 2, + .boot_table = + { + .len = sizeof (local.boot_fdescs) / sizeof (local.boot_fdescs[0]), + .first_unused = 0 + } + }; + +/* Create a new fdesc table and return a pointer to the first fdesc + entry. The fdesc lock must have been acquired already. */ + +static struct fdesc_table * +new_fdesc_table (struct local *l, size_t *size) +{ + size_t old_npages = l->npages; + size_t new_npages = old_npages + old_npages; + struct fdesc_table *new_table; + + /* If someone has just created a new table, we return NULL to tell + the caller to use the new table. */ + if (! COMPARE_AND_SWAP (&l->npages, old_npages, new_npages)) + return (struct fdesc_table *) NULL; + + *size = old_npages * GLRO(dl_pagesize); + new_table = __mmap (NULL, *size, + PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, -1, 0); + if (new_table == MAP_FAILED) + _dl_signal_error (errno, NULL, NULL, + N_("cannot map pages for fdesc table")); + + new_table->len + = (*size - sizeof (*new_table)) / sizeof (struct fdesc); + new_table->first_unused = 1; + return new_table; +} + + +static ElfW(Addr) +make_fdesc (ElfW(Addr) ip, ElfW(Addr) gp) +{ + struct fdesc *fdesc = NULL; + struct fdesc_table *root; + unsigned int old; + struct local *l; + + ELF_MACHINE_LOAD_ADDRESS (l, local); + + retry: + root = l->root; + while (1) + { + old = root->first_unused; + if (old >= root->len) + break; + else if (COMPARE_AND_SWAP (&root->first_unused, old, old + 1)) + { + fdesc = &root->fdesc[old]; + goto install; + } + } + + if (l->free_list) + { + /* Get it from free-list. */ + do + { + fdesc = l->free_list; + if (fdesc == NULL) + goto retry; + } + while (! COMPARE_AND_SWAP ((ElfW(Addr) *) &l->free_list, + (ElfW(Addr)) fdesc, fdesc->ip)); + } + else + { + /* Create a new fdesc table. */ + size_t size; + struct fdesc_table *new_table = new_fdesc_table (l, &size); + + if (new_table == NULL) + goto retry; + + new_table->next = root; + if (! COMPARE_AND_SWAP ((ElfW(Addr) *) &l->root, + (ElfW(Addr)) root, + (ElfW(Addr)) new_table)) + { + /* Someone has just installed a new table. Return NULL to + tell the caller to use the new table. */ + __munmap (new_table, size); + goto retry; + } + + /* Note that the first entry was reserved while allocating the + memory for the new page. */ + fdesc = &new_table->fdesc[0]; + } + + install: + fdesc->ip = ip; + fdesc->gp = gp; + + return (ElfW(Addr)) fdesc; +} + + +static inline ElfW(Addr) * __attribute__ ((always_inline)) +make_fptr_table (struct link_map *map) +{ + const ElfW(Sym) *symtab + = (const void *) D_PTR (map, l_info[DT_SYMTAB]); + const char *strtab = (const void *) D_PTR (map, l_info[DT_STRTAB]); + ElfW(Addr) *fptr_table; + size_t size; + size_t len; + + /* XXX Apparently the only way to find out the size of the dynamic + symbol section is to assume that the string table follows right + afterwards... */ + len = ((strtab - (char *) symtab) + / map->l_info[DT_SYMENT]->d_un.d_val); + size = ((len * sizeof (fptr_table[0]) + GLRO(dl_pagesize) - 1) + & -GLRO(dl_pagesize)); + /* XXX We don't support here in the moment systems without MAP_ANON. + There probably are none for IA-64. In case this is proven wrong + we will have to open /dev/null here and use the file descriptor + instead of the hard-coded -1. */ + fptr_table = __mmap (NULL, size, + PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, + -1, 0); + if (fptr_table == MAP_FAILED) + _dl_signal_error (errno, NULL, NULL, + N_("cannot map pages for fptr table")); + + if (COMPARE_AND_SWAP ((ElfW(Addr) *) &map->l_mach.fptr_table, + (ElfW(Addr)) NULL, (ElfW(Addr)) fptr_table)) + map->l_mach.fptr_table_len = len; + else + __munmap (fptr_table, len * sizeof (fptr_table[0])); + + return map->l_mach.fptr_table; +} + + +ElfW(Addr) +_dl_make_fptr (struct link_map *map, const ElfW(Sym) *sym, + ElfW(Addr) ip) +{ + ElfW(Addr) *ftab = map->l_mach.fptr_table; + const ElfW(Sym) *symtab; + Elf_Symndx symidx; + struct local *l; + + if (__builtin_expect (ftab == NULL, 0)) + ftab = make_fptr_table (map); + + symtab = (const void *) D_PTR (map, l_info[DT_SYMTAB]); + symidx = sym - symtab; + + if (symidx >= map->l_mach.fptr_table_len) + _dl_signal_error (0, NULL, NULL, + N_("internal error: symidx out of range of fptr table")); + + while (ftab[symidx] == 0) + { + /* GOT has already been relocated in elf_get_dynamic_info - + don't try to relocate it again. */ + ElfW(Addr) fdesc + = make_fdesc (ip, map->l_info[DT_PLTGOT]->d_un.d_ptr); + + if (__builtin_expect (COMPARE_AND_SWAP (&ftab[symidx], (ElfW(Addr)) NULL, + fdesc), 1)) + { + /* Noone has updated the entry and the new function + descriptor has been installed. */ +#if 0 + const char *strtab + = (const void *) D_PTR (map, l_info[DT_STRTAB]); + + ELF_MACHINE_LOAD_ADDRESS (l, local); + if (l->root != &l->boot_table + || l->boot_table.first_unused > 20) + _dl_debug_printf ("created fdesc symbol `%s' at %lx\n", + strtab + sym->st_name, ftab[symidx]); +#endif + break; + } + else + { + /* We created a duplicated function descriptor. We put it on + free-list. */ + struct fdesc *f = (struct fdesc *) fdesc; + + ELF_MACHINE_LOAD_ADDRESS (l, local); + + do + f->ip = (ElfW(Addr)) l->free_list; + while (! COMPARE_AND_SWAP ((ElfW(Addr) *) &l->free_list, + f->ip, fdesc)); + } + } + + return ftab[symidx]; +} + + +void +_dl_unmap (struct link_map *map) +{ + ElfW(Addr) *ftab = map->l_mach.fptr_table; + struct fdesc *head = NULL, *tail = NULL; + size_t i; + + __munmap ((void *) map->l_map_start, + map->l_map_end - map->l_map_start); + + if (ftab == NULL) + return; + + /* String together the fdesc structures that are being freed. */ + for (i = 0; i < map->l_mach.fptr_table_len; ++i) + { + if (ftab[i]) + { + *(struct fdesc **) ftab[i] = head; + head = (struct fdesc *) ftab[i]; + if (tail == NULL) + tail = head; + } + } + + /* Prepend the new list to the free_list: */ + if (tail) + do + tail->ip = (ElfW(Addr)) local.free_list; + while (! COMPARE_AND_SWAP ((ElfW(Addr) *) &local.free_list, + tail->ip, (ElfW(Addr)) head)); + + __munmap (ftab, (map->l_mach.fptr_table_len + * sizeof (map->l_mach.fptr_table[0]))); + + map->l_mach.fptr_table = NULL; +} + + +ElfW(Addr) +_dl_lookup_address (const void *address) +{ + ElfW(Addr) addr = (ElfW(Addr)) address; + struct fdesc_table *t; + unsigned long int i; + + for (t = local.root; t != NULL; t = t->next) + { + i = (struct fdesc *) addr - &t->fdesc[0]; + if (i < t->first_unused && addr == (ElfW(Addr)) &t->fdesc[i]) + { + addr = t->fdesc[i].ip; + break; + } + } + + return addr; +} diff --git a/elf/dl-origin.c b/elf/dl-origin.c new file mode 100644 index 0000000000..87619379bc --- /dev/null +++ b/elf/dl-origin.c @@ -0,0 +1,51 @@ +/* Find path of executable. + Copyright (C) 1998, 1999, 2000, 2002, 2004 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <stdlib.h> +#include <string.h> +#include <sys/param.h> +#include <ldsodefs.h> + +#include <dl-dst.h> + + +const char * +_dl_get_origin (void) +{ + char *result = (char *) -1; + /* We use the environment variable LD_ORIGIN_PATH. If it is set make + a copy and strip out trailing slashes. */ + if (GLRO(dl_origin_path) != NULL) + { + size_t len = strlen (GLRO(dl_origin_path)); + result = (char *) malloc (len + 1); + if (result == NULL) + result = (char *) -1; + else + { + char *cp = __mempcpy (result, GLRO(dl_origin_path), len); + while (cp > result + 1 && cp[-1] == '/') + --cp; + *cp = '\0'; + } + } + + return result; +} diff --git a/elf/dl-sbrk.c b/elf/dl-sbrk.c new file mode 100644 index 0000000000..4713a92694 --- /dev/null +++ b/elf/dl-sbrk.c @@ -0,0 +1,5 @@ +/* We can use the normal code but we also know the __curbrk is not exported + from ld.so. */ +extern void *__curbrk attribute_hidden; + +#include <sbrk.c> diff --git a/elf/dl-symaddr.c b/elf/dl-symaddr.c new file mode 100644 index 0000000000..3c850ca835 --- /dev/null +++ b/elf/dl-symaddr.c @@ -0,0 +1,33 @@ +/* Get the symbol address. Generic version. + Copyright (C) 1999, 2000, 2001, 2003 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 + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <ldsodefs.h> +#include <dl-fptr.h> + +void * +_dl_symbol_address (struct link_map *map, const ElfW(Sym) *ref) +{ + ElfW(Addr) value = (map ? map->l_addr : 0) + ref->st_value; + + /* Return the pointer to function descriptor. */ + if (ELFW(ST_TYPE) (ref->st_info) == STT_FUNC) + return (void *) _dl_make_fptr (map, ref, value); + else + return (void *) value; +} diff --git a/elf/dl-sysdep.c b/elf/dl-sysdep.c new file mode 100644 index 0000000000..985e2b8f77 --- /dev/null +++ b/elf/dl-sysdep.c @@ -0,0 +1,590 @@ +/* Operating system support for run-time dynamic linker. Generic Unix version. + Copyright (C) 1995-1998, 2000-2003, 2004, 2005 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 + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <assert.h> +#include <elf.h> +#include <errno.h> +#include <fcntl.h> +#include <libintl.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <sys/mman.h> +#include <ldsodefs.h> +#include <stdio-common/_itoa.h> +#include <fpu_control.h> + +#include <entry.h> +#include <dl-machine.h> +#include <dl-procinfo.h> +#include <dl-osinfo.h> +#include <hp-timing.h> +#include <tls.h> + +#ifdef _DL_FIRST_PLATFORM +# define _DL_FIRST_EXTRA (_DL_FIRST_PLATFORM + _DL_PLATFORMS_COUNT) +#else +# define _DL_FIRST_EXTRA _DL_HWCAP_COUNT +#endif + +extern char **_environ attribute_hidden; +extern void _end attribute_hidden; + +/* Protect SUID program against misuse of file descriptors. */ +extern void __libc_check_standard_fds (void); + +#ifdef NEED_DL_BASE_ADDR +ElfW(Addr) _dl_base_addr; +#endif +int __libc_enable_secure attribute_relro = 0; +INTVARDEF(__libc_enable_secure) +int __libc_multiple_libcs = 0; /* Defining this here avoids the inclusion + of init-first. */ +/* This variable contains the lowest stack address ever used. */ +void *__libc_stack_end attribute_relro = NULL; +rtld_hidden_data_def(__libc_stack_end) +static ElfW(auxv_t) *_dl_auxv attribute_relro; + +#ifndef DL_FIND_ARG_COMPONENTS +# define DL_FIND_ARG_COMPONENTS(cookie, argc, argv, envp, auxp) \ + do { \ + void **_tmp; \ + (argc) = *(long int *) cookie; \ + (argv) = (char **) ((long int *) cookie + 1); \ + (envp) = (argv) + (argc) + 1; \ + for (_tmp = (void **) (envp); *_tmp; ++_tmp) \ + continue; \ + (auxp) = (void *) ++_tmp; \ + } while (0) +#endif + +#ifndef DL_STACK_END +# define DL_STACK_END(cookie) ((void *) (cookie)) +#endif + +ElfW(Addr) +_dl_sysdep_start (void **start_argptr, + void (*dl_main) (const ElfW(Phdr) *phdr, ElfW(Word) phnum, + ElfW(Addr) *user_entry)) +{ + const ElfW(Phdr) *phdr = NULL; + ElfW(Word) phnum = 0; + ElfW(Addr) user_entry; + ElfW(auxv_t) *av; +#ifdef HAVE_AUX_SECURE +# define set_seen(tag) (tag) /* Evaluate for the side effects. */ +# define set_seen_secure() ((void) 0) +#else + uid_t uid = 0; + gid_t gid = 0; + unsigned int seen = 0; +# define set_seen_secure() (seen = -1) +# ifdef HAVE_AUX_XID +# define set_seen(tag) (tag) /* Evaluate for the side effects. */ +# else +# define M(type) (1 << (type)) +# define set_seen(tag) seen |= M ((tag)->a_type) +# endif +#endif +#ifdef NEED_DL_SYSINFO + uintptr_t new_sysinfo = 0; +#endif + + __libc_stack_end = DL_STACK_END (start_argptr); + DL_FIND_ARG_COMPONENTS (start_argptr, _dl_argc, INTUSE(_dl_argv), _environ, + _dl_auxv); + + user_entry = (ElfW(Addr)) ENTRY_POINT; + GLRO(dl_platform) = NULL; /* Default to nothing known about the platform. */ + + for (av = _dl_auxv; av->a_type != AT_NULL; set_seen (av++)) + switch (av->a_type) + { + case AT_PHDR: + phdr = (void *) av->a_un.a_val; + break; + case AT_PHNUM: + phnum = av->a_un.a_val; + break; + case AT_PAGESZ: + GLRO(dl_pagesize) = av->a_un.a_val; + break; + case AT_ENTRY: + user_entry = av->a_un.a_val; + break; +#ifdef NEED_DL_BASE_ADDR + case AT_BASE: + _dl_base_addr = av->a_un.a_val; + break; +#endif +#ifndef HAVE_AUX_SECURE + case AT_UID: + case AT_EUID: + uid ^= av->a_un.a_val; + break; + case AT_GID: + case AT_EGID: + gid ^= av->a_un.a_val; + break; +#endif + case AT_SECURE: +#ifndef HAVE_AUX_SECURE + seen = -1; +#endif + INTUSE(__libc_enable_secure) = av->a_un.a_val; + break; + case AT_PLATFORM: + GLRO(dl_platform) = (void *) av->a_un.a_val; + break; + case AT_HWCAP: + GLRO(dl_hwcap) = (unsigned long int) av->a_un.a_val; + break; + case AT_CLKTCK: + GLRO(dl_clktck) = av->a_un.a_val; + break; + case AT_FPUCW: + GLRO(dl_fpu_control) = av->a_un.a_val; + break; +#ifdef NEED_DL_SYSINFO + case AT_SYSINFO: + new_sysinfo = av->a_un.a_val; + break; +#endif +#if defined NEED_DL_SYSINFO || defined NEED_DL_SYSINFO_DSO + case AT_SYSINFO_EHDR: + GLRO(dl_sysinfo_dso) = (void *) av->a_un.a_val; + break; +#endif +#ifdef DL_PLATFORM_AUXV + DL_PLATFORM_AUXV +#endif + } + +#ifndef HAVE_AUX_SECURE + if (seen != -1) + { + /* Fill in the values we have not gotten from the kernel through the + auxiliary vector. */ +# ifndef HAVE_AUX_XID +# define SEE(UID, var, uid) \ + if ((seen & M (AT_##UID)) == 0) var ^= __get##uid () + SEE (UID, uid, uid); + SEE (EUID, uid, euid); + SEE (GID, gid, gid); + SEE (EGID, gid, egid); +# endif + + /* If one of the two pairs of IDs does not match this is a setuid + or setgid run. */ + INTUSE(__libc_enable_secure) = uid | gid; + } +#endif + +#ifndef HAVE_AUX_PAGESIZE + if (GLRO(dl_pagesize) == 0) + GLRO(dl_pagesize) = __getpagesize (); +#endif + +#if defined NEED_DL_SYSINFO + /* Only set the sysinfo value if we also have the vsyscall DSO. */ + if (GLRO(dl_sysinfo_dso) != 0 && new_sysinfo) + GLRO(dl_sysinfo) = new_sysinfo; +#endif + +#ifdef DL_SYSDEP_INIT + DL_SYSDEP_INIT; +#endif + +#ifdef DL_PLATFORM_INIT + DL_PLATFORM_INIT; +#endif + + /* Determine the length of the platform name. */ + if (GLRO(dl_platform) != NULL) + GLRO(dl_platformlen) = strlen (GLRO(dl_platform)); + + if (__sbrk (0) == &_end) + /* The dynamic linker was run as a program, and so the initial break + starts just after our bss, at &_end. The malloc in dl-minimal.c + will consume the rest of this page, so tell the kernel to move the + break up that far. When the user program examines its break, it + will see this new value and not clobber our data. */ + __sbrk (GLRO(dl_pagesize) + - ((&_end - (void *) 0) & (GLRO(dl_pagesize) - 1))); + + /* If this is a SUID program we make sure that FDs 0, 1, and 2 are + allocated. If necessary we are doing it ourself. If it is not + possible we stop the program. */ + if (__builtin_expect (INTUSE(__libc_enable_secure), 0)) + __libc_check_standard_fds (); + + (*dl_main) (phdr, phnum, &user_entry); + return user_entry; +} + +void +internal_function +_dl_sysdep_start_cleanup (void) +{ +} + +void +internal_function +_dl_show_auxv (void) +{ + char buf[64]; + ElfW(auxv_t) *av; + + /* Terminate string. */ + buf[63] = '\0'; + + /* The following code assumes that the AT_* values are encoded + starting from 0 with AT_NULL, 1 for AT_IGNORE, and all other values + close by (otherwise the array will be too large). In case we have + to support a platform where these requirements are not fulfilled + some alternative implementation has to be used. */ + for (av = _dl_auxv; av->a_type != AT_NULL; ++av) + { + static const struct + { + const char label[20]; + enum { unknown = 0, dec, hex, str, ignore } form; + } auxvars[] = + { + [AT_EXECFD - 2] = { "AT_EXECFD: ", dec }, + [AT_PHDR - 2] = { "AT_PHDR: 0x", hex }, + [AT_PHENT - 2] = { "AT_PHENT: ", dec }, + [AT_PHNUM - 2] = { "AT_PHNUM: ", dec }, + [AT_PAGESZ - 2] = { "AT_PAGESZ: ", dec }, + [AT_BASE - 2] = { "AT_BASE: 0x", hex }, + [AT_FLAGS - 2] = { "AT_FLAGS: 0x", hex }, + [AT_ENTRY - 2] = { "AT_ENTRY: 0x", hex }, + [AT_NOTELF - 2] = { "AT_NOTELF: ", hex }, + [AT_UID - 2] = { "AT_UID: ", dec }, + [AT_EUID - 2] = { "AT_EUID: ", dec }, + [AT_GID - 2] = { "AT_GID: ", dec }, + [AT_EGID - 2] = { "AT_EGID: ", dec }, + [AT_PLATFORM - 2] = { "AT_PLATFORM: ", str }, + [AT_HWCAP - 2] = { "AT_HWCAP: ", hex }, + [AT_CLKTCK - 2] = { "AT_CLKTCK: ", dec }, + [AT_FPUCW - 2] = { "AT_FPUCW: ", hex }, + [AT_DCACHEBSIZE - 2] = { "AT_DCACHEBSIZE: 0x", hex }, + [AT_ICACHEBSIZE - 2] = { "AT_ICACHEBSIZE: 0x", hex }, + [AT_UCACHEBSIZE - 2] = { "AT_UCACHEBSIZE: 0x", hex }, + [AT_IGNOREPPC - 2] = { "AT_IGNOREPPC", ignore }, + [AT_SECURE - 2] = { "AT_SECURE: ", dec }, + [AT_SYSINFO - 2] = { "AT_SYSINFO: 0x", hex }, + [AT_SYSINFO_EHDR - 2] = { "AT_SYSINFO_EHDR: 0x", hex }, + }; + unsigned int idx = (unsigned int) (av->a_type - 2); + + if ((unsigned int) av->a_type < 2u || auxvars[idx].form == ignore) + continue; + + assert (AT_NULL == 0); + assert (AT_IGNORE == 1); + + if (av->a_type == AT_HWCAP) + { + /* This is handled special. */ + if (_dl_procinfo (av->a_un.a_val) == 0) + continue; + } + + if (idx < sizeof (auxvars) / sizeof (auxvars[0]) + && auxvars[idx].form != unknown) + { + const char *val = (char *) av->a_un.a_val; + + if (__builtin_expect (auxvars[idx].form, dec) == dec) + val = _itoa ((unsigned long int) av->a_un.a_val, + buf + sizeof buf - 1, 10, 0); + else if (__builtin_expect (auxvars[idx].form, hex) == hex) + val = _itoa ((unsigned long int) av->a_un.a_val, + buf + sizeof buf - 1, 16, 0); + + _dl_printf ("%s%s\n", auxvars[idx].label, val); + + continue; + } + + /* Unknown value: print a generic line. */ + char buf2[17]; + buf[sizeof (buf2) - 1] = '\0'; + const char *val2 = _itoa ((unsigned long int) av->a_un.a_val, + buf2 + sizeof buf2 - 1, 16, 0); + const char *val = _itoa ((unsigned long int) av->a_type, + buf + sizeof buf - 1, 16, 0); + _dl_printf ("AT_??? (0x%s): 0x%s\n", val, val2); + } +} + + +/* Return an array of useful/necessary hardware capability names. */ +const struct r_strlenpair * +internal_function +_dl_important_hwcaps (const char *platform, size_t platform_len, size_t *sz, + size_t *max_capstrlen) +{ + /* Determine how many important bits are set. */ + uint64_t masked = GLRO(dl_hwcap) & GLRO(dl_hwcap_mask); + size_t cnt = platform != NULL; + size_t n, m; + size_t total; + struct r_strlenpair *temp; + struct r_strlenpair *result; + struct r_strlenpair *rp; + char *cp; + + /* Count the number of bits set in the masked value. */ + for (n = 0; (~((1ULL << n) - 1) & masked) != 0; ++n) + if ((masked & (1ULL << n)) != 0) + ++cnt; + +#if (defined NEED_DL_SYSINFO || defined NEED_DL_SYSINFO_DSO) && defined SHARED + /* The system-supplied DSO can contain a note of type 2, vendor "GNU". + This gives us a list of names to treat as fake hwcap bits. */ + + const char *dsocaps = NULL; + size_t dsocapslen = 0; + if (GLRO(dl_sysinfo_map) != NULL) + { + const ElfW(Phdr) *const phdr = GLRO(dl_sysinfo_map)->l_phdr; + const ElfW(Word) phnum = GLRO(dl_sysinfo_map)->l_phnum; + for (uint_fast16_t i = 0; i < phnum; ++i) + if (phdr[i].p_type == PT_NOTE) + { + const ElfW(Addr) start = (phdr[i].p_vaddr + + GLRO(dl_sysinfo_map)->l_addr); + const struct + { + ElfW(Word) vendorlen; + ElfW(Word) datalen; + ElfW(Word) type; + } *note = (const void *) start; + while ((ElfW(Addr)) (note + 1) - start < phdr[i].p_memsz) + { +#define ROUND(len) (((len) + sizeof (ElfW(Word)) - 1) & -sizeof (ElfW(Word))) + if (note->type == 2 + && note->vendorlen == sizeof "GNU" + && !memcmp ((note + 1), "GNU", sizeof "GNU") + && note->datalen > 2 * sizeof (ElfW(Word)) + 2) + { + const ElfW(Word) *p = ((const void *) (note + 1) + + ROUND (sizeof "GNU")); + cnt += *p++; + ++p; /* Skip mask word. */ + dsocaps = (const char *) p; + dsocapslen = note->datalen - sizeof *p * 2; + break; + } + note = ((const void *) (note + 1) + + ROUND (note->vendorlen) + ROUND (note->datalen)); + } + if (dsocaps != NULL) + break; + } + } +#endif + +#ifdef USE_TLS + /* For TLS enabled builds always add 'tls'. */ + ++cnt; +#else + if (cnt == 0) + { + /* If we no have platform name and no important capability we only + have the base directory to search. */ + result = (struct r_strlenpair *) malloc (sizeof (*result)); + if (result == NULL) + goto no_memory; + + result[0].str = (char *) result; /* Does not really matter. */ + result[0].len = 0; + + *sz = 1; + return result; + } +#endif + + /* Create temporary data structure to generate result table. */ + temp = (struct r_strlenpair *) alloca (cnt * sizeof (*temp)); + m = 0; +#if defined NEED_DL_SYSINFO || defined NEED_DL_SYSINFO_DSO + if (dsocaps != NULL) + { + const ElfW(Word) mask = ((const ElfW(Word) *) dsocaps)[-1]; + GLRO(dl_hwcap) |= (uint64_t) mask << _DL_FIRST_EXTRA; + size_t len; + for (const char *p = dsocaps; p < dsocaps + dsocapslen; p += len + 1) + { + uint_fast8_t bit = *p++; + len = strlen (p); + + /* Skip entries that are not enabled in the mask word. */ + if (__builtin_expect (mask & ((ElfW(Word)) 1 << bit), 1)) + { + temp[m].str = p; + temp[m].len = len; + ++m; + } + else + --cnt; + } + } +#endif + for (n = 0; masked != 0; ++n) + if ((masked & (1ULL << n)) != 0) + { + temp[m].str = _dl_hwcap_string (n); + temp[m].len = strlen (temp[m].str); + masked ^= 1ULL << n; + ++m; + } + if (platform != NULL) + { + temp[m].str = platform; + temp[m].len = platform_len; + ++m; + } +#ifdef USE_TLS + temp[m].str = "tls"; + temp[m].len = 3; + ++m; +#endif + assert (m == cnt); + + /* Determine the total size of all strings together. */ + if (cnt == 1) + total = temp[0].len + 1; + else + { + total = (1UL << (cnt - 2)) * (temp[0].len + temp[cnt - 1].len + 2); + for (n = 1; n + 1 < cnt; ++n) + total += (1UL << (cnt - 3)) * (temp[n].len + 1); + } + + /* The result structure: we use a very compressed way to store the + various combinations of capability names. */ + *sz = 1 << cnt; + result = (struct r_strlenpair *) malloc (*sz * sizeof (*result) + total); + if (result == NULL) + { +#ifndef USE_TLS + no_memory: +#endif + _dl_signal_error (ENOMEM, NULL, NULL, + N_("cannot create capability list")); + } + + if (cnt == 1) + { + result[0].str = (char *) (result + *sz); + result[0].len = temp[0].len + 1; + result[1].str = (char *) (result + *sz); + result[1].len = 0; + cp = __mempcpy ((char *) (result + *sz), temp[0].str, temp[0].len); + *cp = '/'; + *sz = 2; + *max_capstrlen = result[0].len; + + return result; + } + + /* Fill in the information. This follows the following scheme + (indeces from TEMP for four strings): + entry #0: 0, 1, 2, 3 binary: 1111 + #1: 0, 1, 3 1101 + #2: 0, 2, 3 1011 + #3: 0, 3 1001 + This allows the representation of all possible combinations of + capability names in the string. First generate the strings. */ + result[1].str = result[0].str = cp = (char *) (result + *sz); +#define add(idx) \ + cp = __mempcpy (__mempcpy (cp, temp[idx].str, temp[idx].len), "/", 1); + if (cnt == 2) + { + add (1); + add (0); + } + else + { + n = 1 << (cnt - 1); + do + { + n -= 2; + + /* We always add the last string. */ + add (cnt - 1); + + /* Add the strings which have the bit set in N. */ + for (m = cnt - 2; m > 0; --m) + if ((n & (1 << m)) != 0) + add (m); + + /* Always add the first string. */ + add (0); + } + while (n != 0); + } +#undef add + + /* Now we are ready to install the string pointers and length. */ + for (n = 0; n < (1UL << cnt); ++n) + result[n].len = 0; + n = cnt; + do + { + size_t mask = 1 << --n; + + rp = result; + for (m = 1 << cnt; m > 0; ++rp) + if ((--m & mask) != 0) + rp->len += temp[n].len + 1; + } + while (n != 0); + + /* The first half of the strings all include the first string. */ + n = (1 << cnt) - 2; + rp = &result[2]; + while (n != (1UL << (cnt - 1))) + { + if ((--n & 1) != 0) + rp[0].str = rp[-2].str + rp[-2].len; + else + rp[0].str = rp[-1].str; + ++rp; + } + + /* The second half starts right after the first part of the string of + the corresponding entry in the first half. */ + do + { + rp[0].str = rp[-(1 << (cnt - 1))].str + temp[cnt - 1].len + 1; + ++rp; + } + while (--n != 0); + + /* The maximum string length. */ + *max_capstrlen = result[0].len; + + return result; +} diff --git a/elf/dl-tls.c b/elf/dl-tls.c new file mode 100644 index 0000000000..4fed570d5c --- /dev/null +++ b/elf/dl-tls.c @@ -0,0 +1,799 @@ +/* Thread-local storage handling in the ELF dynamic linker. Generic version. + Copyright (C) 2002, 2003, 2004, 2005 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 + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <assert.h> +#include <errno.h> +#include <libintl.h> +#include <signal.h> +#include <stdlib.h> +#include <unistd.h> +#include <sys/param.h> + +#include <tls.h> + +/* We don't need any of this if TLS is not supported. */ +#ifdef USE_TLS + +# include <dl-tls.h> +# include <ldsodefs.h> + +/* Amount of excess space to allocate in the static TLS area + to allow dynamic loading of modules defining IE-model TLS data. */ +# define TLS_STATIC_SURPLUS 64 + DL_NNS * 100 + +/* Value used for dtv entries for which the allocation is delayed. */ +# define TLS_DTV_UNALLOCATED ((void *) -1l) + + +/* Out-of-memory handler. */ +# ifdef SHARED +static void +__attribute__ ((__noreturn__)) +oom (void) +{ + _dl_fatal_printf ("cannot allocate memory for thread-local data: ABORT\n"); +} +# endif + + +size_t +internal_function +_dl_next_tls_modid (void) +{ + size_t result; + + if (__builtin_expect (GL(dl_tls_dtv_gaps), false)) + { + size_t disp = 0; + struct dtv_slotinfo_list *runp = GL(dl_tls_dtv_slotinfo_list); + + /* Note that this branch will never be executed during program + start since there are no gaps at that time. Therefore it + does not matter that the dl_tls_dtv_slotinfo is not allocated + yet when the function is called for the first times. + + NB: the offset +1 is due to the fact that DTV[0] is used + for something else. */ + result = GL(dl_tls_static_nelem) + 1; + if (result <= GL(dl_tls_max_dtv_idx)) + do + { + while (result - disp < runp->len) + { + if (runp->slotinfo[result - disp].map == NULL) + break; + + ++result; + assert (result <= GL(dl_tls_max_dtv_idx) + 1); + } + + if (result - disp < runp->len) + break; + + disp += runp->len; + } + while ((runp = runp->next) != NULL); + + if (result > GL(dl_tls_max_dtv_idx)) + { + /* The new index must indeed be exactly one higher than the + previous high. */ + assert (result == GL(dl_tls_max_dtv_idx) + 1); + /* There is no gap anymore. */ + GL(dl_tls_dtv_gaps) = false; + + goto nogaps; + } + } + else + { + /* No gaps, allocate a new entry. */ + nogaps: + + result = ++GL(dl_tls_max_dtv_idx); + } + + return result; +} + + +# ifdef SHARED +void +internal_function +_dl_determine_tlsoffset (void) +{ + size_t max_align = TLS_TCB_ALIGN; + size_t freetop = 0; + size_t freebottom = 0; + + /* The first element of the dtv slot info list is allocated. */ + assert (GL(dl_tls_dtv_slotinfo_list) != NULL); + /* There is at this point only one element in the + dl_tls_dtv_slotinfo_list list. */ + assert (GL(dl_tls_dtv_slotinfo_list)->next == NULL); + + struct dtv_slotinfo *slotinfo = GL(dl_tls_dtv_slotinfo_list)->slotinfo; + + /* Determining the offset of the various parts of the static TLS + block has several dependencies. In addition we have to work + around bugs in some toolchains. + + Each TLS block from the objects available at link time has a size + and an alignment requirement. The GNU ld computes the alignment + requirements for the data at the positions *in the file*, though. + I.e, it is not simply possible to allocate a block with the size + of the TLS program header entry. The data is layed out assuming + that the first byte of the TLS block fulfills + + p_vaddr mod p_align == &TLS_BLOCK mod p_align + + This means we have to add artificial padding at the beginning of + the TLS block. These bytes are never used for the TLS data in + this module but the first byte allocated must be aligned + according to mod p_align == 0 so that the first byte of the TLS + block is aligned according to p_vaddr mod p_align. This is ugly + and the linker can help by computing the offsets in the TLS block + assuming the first byte of the TLS block is aligned according to + p_align. + + The extra space which might be allocated before the first byte of + the TLS block need not go unused. The code below tries to use + that memory for the next TLS block. This can work if the total + memory requirement for the next TLS block is smaller than the + gap. */ + +# if TLS_TCB_AT_TP + /* We simply start with zero. */ + size_t offset = 0; + + for (size_t cnt = 0; slotinfo[cnt].map != NULL; ++cnt) + { + assert (cnt < GL(dl_tls_dtv_slotinfo_list)->len); + + size_t firstbyte = (-slotinfo[cnt].map->l_tls_firstbyte_offset + & (slotinfo[cnt].map->l_tls_align - 1)); + size_t off; + max_align = MAX (max_align, slotinfo[cnt].map->l_tls_align); + + if (freebottom - freetop >= slotinfo[cnt].map->l_tls_blocksize) + { + off = roundup (freetop + slotinfo[cnt].map->l_tls_blocksize + - firstbyte, slotinfo[cnt].map->l_tls_align) + + firstbyte; + if (off <= freebottom) + { + freetop = off; + + /* XXX For some architectures we perhaps should store the + negative offset. */ + slotinfo[cnt].map->l_tls_offset = off; + continue; + } + } + + off = roundup (offset + slotinfo[cnt].map->l_tls_blocksize - firstbyte, + slotinfo[cnt].map->l_tls_align) + firstbyte; + if (off > offset + slotinfo[cnt].map->l_tls_blocksize + + (freebottom - freetop)) + { + freetop = offset; + freebottom = off - slotinfo[cnt].map->l_tls_blocksize; + } + offset = off; + + /* XXX For some architectures we perhaps should store the + negative offset. */ + slotinfo[cnt].map->l_tls_offset = off; + } + + GL(dl_tls_static_used) = offset; + GL(dl_tls_static_size) = (roundup (offset + TLS_STATIC_SURPLUS, max_align) + + TLS_TCB_SIZE); +# elif TLS_DTV_AT_TP + /* The TLS blocks start right after the TCB. */ + size_t offset = TLS_TCB_SIZE; + + for (size_t cnt = 0; slotinfo[cnt].map != NULL; ++cnt) + { + assert (cnt < GL(dl_tls_dtv_slotinfo_list)->len); + + size_t firstbyte = (-slotinfo[cnt].map->l_tls_firstbyte_offset + & (slotinfo[cnt].map->l_tls_align - 1)); + size_t off; + max_align = MAX (max_align, slotinfo[cnt].map->l_tls_align); + + if (slotinfo[cnt].map->l_tls_blocksize <= freetop - freebottom) + { + off = roundup (freebottom, slotinfo[cnt].map->l_tls_align); + if (off - freebottom < firstbyte) + off += slotinfo[cnt].map->l_tls_align; + if (off + slotinfo[cnt].map->l_tls_blocksize - firstbyte <= freetop) + { + slotinfo[cnt].map->l_tls_offset = off - firstbyte; + freebottom = (off + slotinfo[cnt].map->l_tls_blocksize + - firstbyte); + continue; + } + } + + off = roundup (offset, slotinfo[cnt].map->l_tls_align); + if (off - offset < firstbyte) + off += slotinfo[cnt].map->l_tls_align; + + slotinfo[cnt].map->l_tls_offset = off - firstbyte; + if (off - firstbyte - offset > freetop - freebottom) + { + freebottom = offset; + freetop = off - firstbyte; + } + + offset = off + slotinfo[cnt].map->l_tls_blocksize - firstbyte; + } + + GL(dl_tls_static_used) = offset; + GL(dl_tls_static_size) = roundup (offset + TLS_STATIC_SURPLUS, + TLS_TCB_ALIGN); +# else +# error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined" +# endif + + /* The alignment requirement for the static TLS block. */ + GL(dl_tls_static_align) = max_align; +} + + +/* This is called only when the data structure setup was skipped at startup, + when there was no need for it then. Now we have dynamically loaded + something needing TLS, or libpthread needs it. */ +int +internal_function +_dl_tls_setup (void) +{ + assert (GL(dl_tls_dtv_slotinfo_list) == NULL); + assert (GL(dl_tls_max_dtv_idx) == 0); + + const size_t nelem = 2 + TLS_SLOTINFO_SURPLUS; + + GL(dl_tls_dtv_slotinfo_list) + = calloc (1, (sizeof (struct dtv_slotinfo_list) + + nelem * sizeof (struct dtv_slotinfo))); + if (GL(dl_tls_dtv_slotinfo_list) == NULL) + return -1; + + GL(dl_tls_dtv_slotinfo_list)->len = nelem; + + /* Number of elements in the static TLS block. It can't be zero + because of various assumptions. The one element is null. */ + GL(dl_tls_static_nelem) = GL(dl_tls_max_dtv_idx) = 1; + + /* This initializes more variables for us. */ + _dl_determine_tlsoffset (); + + return 0; +} +rtld_hidden_def (_dl_tls_setup) +# endif + +static void * +internal_function +allocate_dtv (void *result) +{ + dtv_t *dtv; + size_t dtv_length; + + /* We allocate a few more elements in the dtv than are needed for the + initial set of modules. This should avoid in most cases expansions + of the dtv. */ + dtv_length = GL(dl_tls_max_dtv_idx) + DTV_SURPLUS; + dtv = calloc (dtv_length + 2, sizeof (dtv_t)); + if (dtv != NULL) + { + /* This is the initial length of the dtv. */ + dtv[0].counter = dtv_length; + + /* The rest of the dtv (including the generation counter) is + Initialize with zero to indicate nothing there. */ + + /* Add the dtv to the thread data structures. */ + INSTALL_DTV (result, dtv); + } + else + result = NULL; + + return result; +} + + +/* Get size and alignment requirements of the static TLS block. */ +void +internal_function +_dl_get_tls_static_info (size_t *sizep, size_t *alignp) +{ + *sizep = GL(dl_tls_static_size); + *alignp = GL(dl_tls_static_align); +} + + +void * +internal_function +_dl_allocate_tls_storage (void) +{ + void *result; + size_t size = GL(dl_tls_static_size); + +# if TLS_DTV_AT_TP + /* Memory layout is: + [ TLS_PRE_TCB_SIZE ] [ TLS_TCB_SIZE ] [ TLS blocks ] + ^ This should be returned. */ + size += (TLS_PRE_TCB_SIZE + GL(dl_tls_static_align) - 1) + & ~(GL(dl_tls_static_align) - 1); +# endif + + /* Allocate a correctly aligned chunk of memory. */ + result = __libc_memalign (GL(dl_tls_static_align), size); + if (__builtin_expect (result != NULL, 1)) + { + /* Allocate the DTV. */ + void *allocated = result; + +# if TLS_TCB_AT_TP + /* The TCB follows the TLS blocks. */ + result = (char *) result + size - TLS_TCB_SIZE; + + /* Clear the TCB data structure. We can't ask the caller (i.e. + libpthread) to do it, because we will initialize the DTV et al. */ + memset (result, '\0', TLS_TCB_SIZE); +# elif TLS_DTV_AT_TP + result = (char *) result + size - GL(dl_tls_static_size); + + /* Clear the TCB data structure and TLS_PRE_TCB_SIZE bytes before it. + We can't ask the caller (i.e. libpthread) to do it, because we will + initialize the DTV et al. */ + memset ((char *) result - TLS_PRE_TCB_SIZE, '\0', + TLS_PRE_TCB_SIZE + TLS_TCB_SIZE); +# endif + + result = allocate_dtv (result); + if (result == NULL) + free (allocated); + } + + return result; +} + + +void * +internal_function +_dl_allocate_tls_init (void *result) +{ + if (result == NULL) + /* The memory allocation failed. */ + return NULL; + + dtv_t *dtv = GET_DTV (result); + struct dtv_slotinfo_list *listp; + size_t total = 0; + size_t maxgen = 0; + + /* We have to prepare the dtv for all currently loaded modules using + TLS. For those which are dynamically loaded we add the values + indicating deferred allocation. */ + listp = GL(dl_tls_dtv_slotinfo_list); + while (1) + { + size_t cnt; + + for (cnt = total == 0 ? 1 : 0; cnt < listp->len; ++cnt) + { + struct link_map *map; + void *dest; + + /* Check for the total number of used slots. */ + if (total + cnt > GL(dl_tls_max_dtv_idx)) + break; + + map = listp->slotinfo[cnt].map; + if (map == NULL) + /* Unused entry. */ + continue; + + /* Keep track of the maximum generation number. This might + not be the generation counter. */ + maxgen = MAX (maxgen, listp->slotinfo[cnt].gen); + + if (map->l_tls_offset == NO_TLS_OFFSET) + { + /* For dynamically loaded modules we simply store + the value indicating deferred allocation. */ + dtv[map->l_tls_modid].pointer.val = TLS_DTV_UNALLOCATED; + dtv[map->l_tls_modid].pointer.is_static = false; + continue; + } + + assert (map->l_tls_modid == cnt); + assert (map->l_tls_blocksize >= map->l_tls_initimage_size); +# if TLS_TCB_AT_TP + assert ((size_t) map->l_tls_offset >= map->l_tls_blocksize); + dest = (char *) result - map->l_tls_offset; +# elif TLS_DTV_AT_TP + dest = (char *) result + map->l_tls_offset; +# else +# error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined" +# endif + + /* Copy the initialization image and clear the BSS part. */ + dtv[map->l_tls_modid].pointer.val = dest; + dtv[map->l_tls_modid].pointer.is_static = true; + memset (__mempcpy (dest, map->l_tls_initimage, + map->l_tls_initimage_size), '\0', + map->l_tls_blocksize - map->l_tls_initimage_size); + } + + total += cnt; + if (total >= GL(dl_tls_max_dtv_idx)) + break; + + listp = listp->next; + assert (listp != NULL); + } + + /* The DTV version is up-to-date now. */ + dtv[0].counter = maxgen; + + return result; +} +rtld_hidden_def (_dl_allocate_tls_init) + +void * +internal_function +_dl_allocate_tls (void *mem) +{ + return _dl_allocate_tls_init (mem == NULL + ? _dl_allocate_tls_storage () + : allocate_dtv (mem)); +} +rtld_hidden_def (_dl_allocate_tls) + + +void +internal_function +_dl_deallocate_tls (void *tcb, bool dealloc_tcb) +{ + dtv_t *dtv = GET_DTV (tcb); + + /* We need to free the memory allocated for non-static TLS. */ + for (size_t cnt = 0; cnt < dtv[-1].counter; ++cnt) + if (! dtv[1 + cnt].pointer.is_static + && dtv[1 + cnt].pointer.val != TLS_DTV_UNALLOCATED) + free (dtv[1 + cnt].pointer.val); + + /* The array starts with dtv[-1]. */ +#ifdef SHARED + if (dtv != GL(dl_initial_dtv)) +#endif + free (dtv - 1); + + if (dealloc_tcb) + { +# if TLS_TCB_AT_TP + /* The TCB follows the TLS blocks. Back up to free the whole block. */ + tcb -= GL(dl_tls_static_size) - TLS_TCB_SIZE; +# elif TLS_DTV_AT_TP + /* Back up the TLS_PRE_TCB_SIZE bytes. */ + tcb -= (TLS_PRE_TCB_SIZE + GL(dl_tls_static_align) - 1) + & ~(GL(dl_tls_static_align) - 1); +# endif + free (tcb); + } +} +rtld_hidden_def (_dl_deallocate_tls) + + +# ifdef SHARED +/* The __tls_get_addr function has two basic forms which differ in the + arguments. The IA-64 form takes two parameters, the module ID and + offset. The form used, among others, on IA-32 takes a reference to + a special structure which contain the same information. The second + form seems to be more often used (in the moment) so we default to + it. Users of the IA-64 form have to provide adequate definitions + of the following macros. */ +# ifndef GET_ADDR_ARGS +# define GET_ADDR_ARGS tls_index *ti +# endif +# ifndef GET_ADDR_MODULE +# define GET_ADDR_MODULE ti->ti_module +# endif +# ifndef GET_ADDR_OFFSET +# define GET_ADDR_OFFSET ti->ti_offset +# endif + + +static void * +allocate_and_init (struct link_map *map) +{ + void *newp; + + newp = __libc_memalign (map->l_tls_align, map->l_tls_blocksize); + if (newp == NULL) + oom (); + + /* Initialize the memory. */ + memset (__mempcpy (newp, map->l_tls_initimage, map->l_tls_initimage_size), + '\0', map->l_tls_blocksize - map->l_tls_initimage_size); + + return newp; +} + + +struct link_map * +_dl_update_slotinfo (unsigned long int req_modid) +{ + struct link_map *the_map = NULL; + dtv_t *dtv = THREAD_DTV (); + + /* The global dl_tls_dtv_slotinfo array contains for each module + index the generation counter current when the entry was created. + This array never shrinks so that all module indices which were + valid at some time can be used to access it. Before the first + use of a new module index in this function the array was extended + appropriately. Access also does not have to be guarded against + modifications of the array. It is assumed that pointer-size + values can be read atomically even in SMP environments. It is + possible that other threads at the same time dynamically load + code and therefore add to the slotinfo list. This is a problem + since we must not pick up any information about incomplete work. + The solution to this is to ignore all dtv slots which were + created after the one we are currently interested. We know that + dynamic loading for this module is completed and this is the last + load operation we know finished. */ + unsigned long int idx = req_modid; + struct dtv_slotinfo_list *listp = GL(dl_tls_dtv_slotinfo_list); + + while (idx >= listp->len) + { + idx -= listp->len; + listp = listp->next; + } + + if (dtv[0].counter < listp->slotinfo[idx].gen) + { + /* The generation counter for the slot is higher than what the + current dtv implements. We have to update the whole dtv but + only those entries with a generation counter <= the one for + the entry we need. */ + size_t new_gen = listp->slotinfo[idx].gen; + size_t total = 0; + + /* We have to look through the entire dtv slotinfo list. */ + listp = GL(dl_tls_dtv_slotinfo_list); + do + { + for (size_t cnt = total == 0 ? 1 : 0; cnt < listp->len; ++cnt) + { + size_t gen = listp->slotinfo[cnt].gen; + + if (gen > new_gen) + /* This is a slot for a generation younger than the + one we are handling now. It might be incompletely + set up so ignore it. */ + continue; + + /* If the entry is older than the current dtv layout we + know we don't have to handle it. */ + if (gen <= dtv[0].counter) + continue; + + /* If there is no map this means the entry is empty. */ + struct link_map *map = listp->slotinfo[cnt].map; + if (map == NULL) + { + /* If this modid was used at some point the memory + might still be allocated. */ + if (! dtv[total + cnt].pointer.is_static + && dtv[total + cnt].pointer.val != TLS_DTV_UNALLOCATED) + { + free (dtv[total + cnt].pointer.val); + dtv[total + cnt].pointer.val = TLS_DTV_UNALLOCATED; + } + + continue; + } + + /* Check whether the current dtv array is large enough. */ + size_t modid = map->l_tls_modid; + assert (total + cnt == modid); + if (dtv[-1].counter < modid) + { + /* Reallocate the dtv. */ + dtv_t *newp; + size_t newsize = GL(dl_tls_max_dtv_idx) + DTV_SURPLUS; + size_t oldsize = dtv[-1].counter; + + assert (map->l_tls_modid <= newsize); + + if (dtv == GL(dl_initial_dtv)) + { + /* This is the initial dtv that was allocated + during rtld startup using the dl-minimal.c + malloc instead of the real malloc. We can't + free it, we have to abandon the old storage. */ + + newp = malloc ((2 + newsize) * sizeof (dtv_t)); + if (newp == NULL) + oom (); + memcpy (newp, &dtv[-1], oldsize * sizeof (dtv_t)); + } + else + { + newp = realloc (&dtv[-1], + (2 + newsize) * sizeof (dtv_t)); + if (newp == NULL) + oom (); + } + + newp[0].counter = newsize; + + /* Clear the newly allocated part. */ + memset (newp + 2 + oldsize, '\0', + (newsize - oldsize) * sizeof (dtv_t)); + + /* Point dtv to the generation counter. */ + dtv = &newp[1]; + + /* Install this new dtv in the thread data + structures. */ + INSTALL_NEW_DTV (dtv); + } + + /* If there is currently memory allocate for this + dtv entry free it. */ + /* XXX Ideally we will at some point create a memory + pool. */ + if (! dtv[modid].pointer.is_static + && dtv[modid].pointer.val != TLS_DTV_UNALLOCATED) + /* Note that free is called for NULL is well. We + deallocate even if it is this dtv entry we are + supposed to load. The reason is that we call + memalign and not malloc. */ + free (dtv[modid].pointer.val); + + /* This module is loaded dynamically- We defer memory + allocation. */ + dtv[modid].pointer.is_static = false; + dtv[modid].pointer.val = TLS_DTV_UNALLOCATED; + + if (modid == req_modid) + the_map = map; + } + + total += listp->len; + } + while ((listp = listp->next) != NULL); + + /* This will be the new maximum generation counter. */ + dtv[0].counter = new_gen; + } + + return the_map; +} + + +/* The generic dynamic and local dynamic model cannot be used in + statically linked applications. */ +void * +__tls_get_addr (GET_ADDR_ARGS) +{ + dtv_t *dtv = THREAD_DTV (); + struct link_map *the_map = NULL; + void *p; + + if (__builtin_expect (dtv[0].counter != GL(dl_tls_generation), 0)) + the_map = _dl_update_slotinfo (GET_ADDR_MODULE); + + p = dtv[GET_ADDR_MODULE].pointer.val; + + if (__builtin_expect (p == TLS_DTV_UNALLOCATED, 0)) + { + /* The allocation was deferred. Do it now. */ + if (the_map == NULL) + { + /* Find the link map for this module. */ + size_t idx = GET_ADDR_MODULE; + struct dtv_slotinfo_list *listp = GL(dl_tls_dtv_slotinfo_list); + + while (idx >= listp->len) + { + idx -= listp->len; + listp = listp->next; + } + + the_map = listp->slotinfo[idx].map; + } + + p = dtv[GET_ADDR_MODULE].pointer.val = allocate_and_init (the_map); + dtv[GET_ADDR_MODULE].pointer.is_static = false; + } + + return (char *) p + GET_ADDR_OFFSET; +} +# endif + + + +void +_dl_add_to_slotinfo (struct link_map *l) +{ + /* Now that we know the object is loaded successfully add + modules containing TLS data to the dtv info table. We + might have to increase its size. */ + struct dtv_slotinfo_list *listp; + struct dtv_slotinfo_list *prevp; + size_t idx = l->l_tls_modid; + + /* Find the place in the dtv slotinfo list. */ + listp = GL(dl_tls_dtv_slotinfo_list); + prevp = NULL; /* Needed to shut up gcc. */ + do + { + /* Does it fit in the array of this list element? */ + if (idx < listp->len) + break; + idx -= listp->len; + prevp = listp; + listp = listp->next; + } + while (listp != NULL); + + if (listp == NULL) + { + /* When we come here it means we have to add a new element + to the slotinfo list. And the new module must be in + the first slot. */ + assert (idx == 0); + + listp = prevp->next = (struct dtv_slotinfo_list *) + malloc (sizeof (struct dtv_slotinfo_list) + + TLS_SLOTINFO_SURPLUS * sizeof (struct dtv_slotinfo)); + if (listp == NULL) + { + /* We ran out of memory. We will simply fail this + call but don't undo anything we did so far. The + application will crash or be terminated anyway very + soon. */ + + /* We have to do this since some entries in the dtv + slotinfo array might already point to this + generation. */ + ++GL(dl_tls_generation); + + _dl_signal_error (ENOMEM, "dlopen", NULL, N_("\ +cannot create TLS data structures")); + } + + listp->len = TLS_SLOTINFO_SURPLUS; + listp->next = NULL; + memset (listp->slotinfo, '\0', + TLS_SLOTINFO_SURPLUS * sizeof (struct dtv_slotinfo)); + } + + /* Add the information into the slotinfo data structure. */ + listp->slotinfo[idx].map = l; + listp->slotinfo[idx].gen = GL(dl_tls_generation) + 1; +} +#endif /* use TLS */ diff --git a/elf/dl-trampoline.c b/elf/dl-trampoline.c new file mode 100644 index 0000000000..3ca89f3879 --- /dev/null +++ b/elf/dl-trampoline.c @@ -0,0 +1 @@ +#error "Architecture specific PLT trampolines must be defined." |