diff options
Diffstat (limited to 'elf/dl-open.c')
| -rw-r--r-- | elf/dl-open.c | 180 |
1 files changed, 129 insertions, 51 deletions
diff --git a/elf/dl-open.c b/elf/dl-open.c index 8d057f82eb..32e7caac7f 100644 --- a/elf/dl-open.c +++ b/elf/dl-open.c @@ -1,5 +1,5 @@ /* Load a shared object at runtime, relocate it, and run its initializer. - Copyright (C) 1996-2004, 2005, 2006 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 @@ -31,6 +31,8 @@ #include <ldsodefs.h> #include <bp-sym.h> #include <caller.h> +#include <sysdep-cancel.h> +#include <tls.h> #include <dl-dst.h> @@ -96,17 +98,17 @@ add_to_global (struct link_map *new) in an realloc() call. Therefore we allocate a completely new array the first time we have to add something to the locale scope. */ - if (GL(dl_ns)[new->l_ns]._ns_global_scope_alloc == 0) + struct link_namespaces *ns = &GL(dl_ns)[new->l_ns]; + if (ns->_ns_global_scope_alloc == 0) { /* This is the first dynamic object given global scope. */ - GL(dl_ns)[new->l_ns]._ns_global_scope_alloc - = GL(dl_ns)[new->l_ns]._ns_main_searchlist->r_nlist + to_add + 8; + ns->_ns_global_scope_alloc + = ns->_ns_main_searchlist->r_nlist + to_add + 8; new_global = (struct link_map **) - malloc (GL(dl_ns)[new->l_ns]._ns_global_scope_alloc - * sizeof (struct link_map *)); + malloc (ns->_ns_global_scope_alloc * sizeof (struct link_map *)); if (new_global == NULL) { - GL(dl_ns)[new->l_ns]._ns_global_scope_alloc = 0; + ns->_ns_global_scope_alloc = 0; nomem: _dl_signal_error (ENOMEM, new->l_libname->name, NULL, N_("cannot extend global scope")); @@ -114,29 +116,39 @@ add_to_global (struct link_map *new) } /* Copy over the old entries. */ - GL(dl_ns)[new->l_ns]._ns_main_searchlist->r_list - = memcpy (new_global, - GL(dl_ns)[new->l_ns]._ns_main_searchlist->r_list, - (GL(dl_ns)[new->l_ns]._ns_main_searchlist->r_nlist + ns->_ns_main_searchlist->r_list + = memcpy (new_global, ns->_ns_main_searchlist->r_list, + (ns->_ns_main_searchlist->r_nlist * sizeof (struct link_map *))); } - else if (GL(dl_ns)[new->l_ns]._ns_main_searchlist->r_nlist + to_add - > GL(dl_ns)[new->l_ns]._ns_global_scope_alloc) + else if (ns->_ns_main_searchlist->r_nlist + to_add + > ns->_ns_global_scope_alloc) { /* We have to extend the existing array of link maps in the main map. */ + struct link_map **old_global + = GL(dl_ns)[new->l_ns]._ns_main_searchlist->r_list; + size_t new_nalloc = ((ns->_ns_global_scope_alloc + to_add) * 2); + new_global = (struct link_map **) - realloc (GL(dl_ns)[new->l_ns]._ns_main_searchlist->r_list, - ((GL(dl_ns)[new->l_ns]._ns_global_scope_alloc + to_add + 8) - * sizeof (struct link_map *))); + malloc (new_nalloc * sizeof (struct link_map *)); if (new_global == NULL) goto nomem; - GL(dl_ns)[new->l_ns]._ns_global_scope_alloc += to_add + 8; - GL(dl_ns)[new->l_ns]._ns_main_searchlist->r_list = new_global; + memcpy (new_global, old_global, + ns->_ns_global_scope_alloc * sizeof (struct link_map *)); + + ns->_ns_global_scope_alloc = new_nalloc; + ns->_ns_main_searchlist->r_list = new_global; + + if (!RTLD_SINGLE_THREAD_P) + THREAD_GSCOPE_WAIT (); + + free (old_global); } /* Now add the new entries. */ + unsigned int new_nlist = ns->_ns_main_searchlist->r_nlist; for (cnt = 0; cnt < new->l_searchlist.r_nlist; ++cnt) { struct link_map *map = new->l_searchlist.r_list[cnt]; @@ -144,15 +156,49 @@ add_to_global (struct link_map *new) if (map->l_global == 0) { map->l_global = 1; - GL(dl_ns)[new->l_ns]._ns_main_searchlist->r_list[GL(dl_ns)[new->l_ns]._ns_main_searchlist->r_nlist] - = map; - ++GL(dl_ns)[new->l_ns]._ns_main_searchlist->r_nlist; + ns->_ns_main_searchlist->r_list[new_nlist++] = map; } } + atomic_write_barrier (); + ns->_ns_main_searchlist->r_nlist = new_nlist; return 0; } +int +_dl_scope_free (struct r_scope_elem **old) +{ + struct dl_scope_free_list *fsl; +#define DL_SCOPE_FREE_LIST_SIZE (sizeof (fsl->list) / sizeof (fsl->list[0])) + + if (RTLD_SINGLE_THREAD_P) + free (old); + else if ((fsl = GL(dl_scope_free_list)) == NULL) + { + GL(dl_scope_free_list) = fsl = malloc (sizeof (*fsl)); + if (fsl == NULL) + { + THREAD_GSCOPE_WAIT (); + free (old); + return 1; + } + else + { + fsl->list[0] = old; + fsl->count = 1; + } + } + else if (fsl->count < DL_SCOPE_FREE_LIST_SIZE) + fsl->list[fsl->count++] = old; + else + { + THREAD_GSCOPE_WAIT (); + while (fsl->count > 0) + free (fsl->list[--fsl->count]); + return 1; + } + return 0; +} static void dl_open_worker (void *a) @@ -160,7 +206,7 @@ dl_open_worker (void *a) struct dl_open_args *args = a; const char *file = args->file; int mode = args->mode; - struct link_map *new, *l; + struct link_map *new; int lazy; unsigned int i; #ifdef USE_TLS @@ -187,13 +233,14 @@ dl_open_worker (void *a) By default we assume this is the main application. */ call_map = GL(dl_ns)[LM_ID_BASE]._ns_loaded; + struct link_map *l; for (Lmid_t ns = 0; ns < DL_NNS; ++ns) for (l = GL(dl_ns)[ns]._ns_loaded; l != NULL; l = l->l_next) if (caller_dlopen >= (const void *) l->l_map_start - && caller_dlopen < (const void *) l->l_map_end) + && caller_dlopen < (const void *) l->l_map_end + && (l->l_contiguous + || _dl_addr_inside_object (l, (ElfW(Addr)) caller_dlopen))) { - /* There must be exactly one DSO for the range of the virtual - memory. Otherwise something is really broken. */ assert (ns == l->l_ns); call_map = l; goto found_caller; @@ -326,7 +373,7 @@ dl_open_worker (void *a) /* Relocate the objects loaded. We do this in reverse order so that copy relocs of earlier objects overwrite the data written by later objects. */ - l = new; + struct link_map *l = new; while (l->l_next) l = l->l_next; while (1) @@ -379,6 +426,8 @@ dl_open_worker (void *a) while (*runp != NULL) { + if (*runp == &new->l_searchlist) + break; ++cnt; ++runp; } @@ -391,35 +440,45 @@ dl_open_worker (void *a) { /* The 'r_scope' array is too small. Allocate a new one dynamically. */ + size_t new_size; struct r_scope_elem **newp; - size_t new_size = imap->l_scope_max * 2; - if (imap->l_scope == imap->l_scope_mem) +#define SCOPE_ELEMS(imap) \ + (sizeof (imap->l_scope_mem) / sizeof (imap->l_scope_mem[0])) + + if (imap->l_scope != imap->l_scope_mem + && imap->l_scope_max < SCOPE_ELEMS (imap)) { - newp = (struct r_scope_elem **) - malloc (new_size * sizeof (struct r_scope_elem *)); - if (newp == NULL) - _dl_signal_error (ENOMEM, "dlopen", NULL, - N_("cannot create scope list")); - imap->l_scope = memcpy (newp, imap->l_scope, - cnt * sizeof (imap->l_scope[0])); + new_size = SCOPE_ELEMS (imap); + newp = imap->l_scope_mem; } else { + new_size = imap->l_scope_max * 2; newp = (struct r_scope_elem **) - realloc (imap->l_scope, - new_size * sizeof (struct r_scope_elem *)); + malloc (new_size * sizeof (struct r_scope_elem *)); if (newp == NULL) _dl_signal_error (ENOMEM, "dlopen", NULL, N_("cannot create scope list")); - imap->l_scope = newp; } + memcpy (newp, imap->l_scope, cnt * sizeof (imap->l_scope[0])); + struct r_scope_elem **old = imap->l_scope; + + imap->l_scope = newp; + + if (old != imap->l_scope_mem) + _dl_scope_free (old); + imap->l_scope_max = new_size; } - imap->l_scope[cnt++] = &new->l_searchlist; - imap->l_scope[cnt] = NULL; + /* First terminate the extended list. Otherwise a thread + might use the new last element and then use the garbage + at offset IDX+1. */ + imap->l_scope[cnt + 1] = NULL; + atomic_write_barrier (); + imap->l_scope[cnt] = &new->l_searchlist; } #if USE_TLS /* Only add TLS memory if this object is loaded now and @@ -547,15 +606,9 @@ no more namespaces available for dlmopen()")); _dl_unload_cache (); #endif - /* Release the lock. */ - __rtld_lock_unlock_recursive (GL(dl_load_lock)); - + /* See if an error occurred during loading. */ if (__builtin_expect (errstring != NULL, 0)) { - /* Some error occurred during loading. */ - char *local_errstring; - size_t len_errstring; - /* Remove the object from memory. It may be in an inconsistent state if relocation failed, for example. */ if (args.map) @@ -572,12 +625,18 @@ no more namespaces available for dlmopen()")); GL(dl_tls_dtv_gaps) = true; #endif - _dl_close (args.map); + _dl_close_worker (args.map); } + assert (_dl_debug_initialize (0, args.nsid)->r_state == RT_CONSISTENT); + + /* Release the lock. */ + __rtld_lock_unlock_recursive (GL(dl_load_lock)); + /* Make a local copy of the error string so that we can release the memory allocated for it. */ - len_errstring = strlen (errstring) + 1; + size_t len_errstring = strlen (errstring) + 1; + char *local_errstring; if (objname == errstring + len_errstring) { size_t total_len = len_errstring + strlen (objname) + 1; @@ -594,14 +653,15 @@ no more namespaces available for dlmopen()")); if (malloced) free ((char *) errstring); - assert (_dl_debug_initialize (0, args.nsid)->r_state == RT_CONSISTENT); - /* Reraise the error. */ _dl_signal_error (errcode, objname, NULL, local_errstring); } assert (_dl_debug_initialize (0, args.nsid)->r_state == RT_CONSISTENT); + /* Release the lock. */ + __rtld_lock_unlock_recursive (GL(dl_load_lock)); + #ifndef SHARED DL_STATIC_INIT (args.map); #endif @@ -637,3 +697,21 @@ show_scope (struct link_map *new) } } #endif + +#ifdef IS_IN_rtld +/* 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; +} +#endif |