/* Storage management for the chain of loaded shared objects.
-Copyright (C) 1995 Free Software Foundation, Inc.
-This file is part of the GNU C Library.
+ Copyright (C) 1995-2019 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 Library General Public License as
-published by the Free Software Foundation; either version 2 of the
-License, or (at your option) any later version.
+ 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
-Library General Public License for more details.
+ 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 Library General Public
-License along with the GNU C Library; see the file COPYING.LIB. If
-not, write to the Free Software Foundation, Inc., 675 Mass Ave,
-Cambridge, MA 02139, USA. */
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
-#include <link.h>
-#include <assert.h>
+#include <errno.h>
#include <string.h>
#include <stdlib.h>
-#include <errno.h>
+#include <unistd.h>
+#include <ldsodefs.h>
+#include <assert.h>
+
+
+/* Add the new link_map NEW to the end of the namespace list. */
+void
+_dl_add_to_namespace_list (struct link_map *new, Lmid_t nsid)
+{
+ /* We modify the list of loaded objects. */
+ __rtld_lock_lock_recursive (GL(dl_load_write_lock));
+
+ if (GL(dl_ns)[nsid]._ns_loaded != NULL)
+ {
+ struct link_map *l = GL(dl_ns)[nsid]._ns_loaded;
+ while (l->l_next != NULL)
+ l = l->l_next;
+ new->l_prev = l;
+ /* new->l_next = NULL; Would be necessary but we use calloc. */
+ l->l_next = new;
+ }
+ else
+ GL(dl_ns)[nsid]._ns_loaded = new;
+ ++GL(dl_ns)[nsid]._ns_nloaded;
+ new->l_serial = GL(dl_load_adds);
+ ++GL(dl_load_adds);
-/* List of objects currently loaded. */
-struct link_map *_dl_loaded;
+ __rtld_lock_unlock_recursive (GL(dl_load_write_lock));
+}
-/* Tail of that list which were loaded at startup. */
-struct link_map *_dl_startup_loaded;
/* Allocate a `struct link_map' for a new object being loaded,
and enter it into the _dl_loaded list. */
-
struct link_map *
-_dl_new_object (char *realname, const char *libname, int type)
+_dl_new_object (char *realname, const char *libname, int type,
+ struct link_map *loader, int mode, Lmid_t nsid)
{
- struct link_map *new = malloc (sizeof *new);
- if (! new)
- _dl_signal_error (ENOMEM, libname,
- "cannot allocate shared object descriptor");
-
- memset (new, 0, sizeof *new);
- new->l_name = realname;
- new->l_libname = libname;
+#ifdef SHARED
+ unsigned int naudit;
+ if (__glibc_unlikely ((mode & __RTLD_OPENEXEC) != 0))
+ {
+ assert (type == lt_executable);
+ assert (nsid == LM_ID_BASE);
+
+ /* Ignore the specified libname for the main executable. It is
+ only known with an explicit loader invocation. */
+ libname = "";
+
+ /* We create the map for the executable before we know whether
+ we have auditing libraries and if yes, how many. Assume the
+ worst. */
+ naudit = DL_NNS;
+ }
+ else
+ naudit = GLRO (dl_naudit);
+#endif
+
+ size_t libname_len = strlen (libname) + 1;
+ struct link_map *new;
+ struct libname_list *newname;
+#ifdef SHARED
+ size_t audit_space = naudit * sizeof (new->l_audit[0]);
+#else
+# define audit_space 0
+#endif
+
+ new = (struct link_map *) calloc (sizeof (*new) + audit_space
+ + sizeof (struct link_map *)
+ + sizeof (*newname) + libname_len, 1);
+ if (new == NULL)
+ return NULL;
+
+ new->l_real = new;
+ new->l_symbolic_searchlist.r_list = (struct link_map **) ((char *) (new + 1)
+ + audit_space);
+
+ new->l_libname = newname
+ = (struct libname_list *) (new->l_symbolic_searchlist.r_list + 1);
+ newname->name = (char *) memcpy (newname + 1, libname, libname_len);
+ /* newname->next = NULL; We use calloc therefore not necessary. */
+ newname->dont_free = 1;
+
+ /* When we create the executable link map, or a VDSO link map, we start
+ with "" for the l_name. In these cases "" points to ld.so rodata
+ and won't get dumped during core file generation. Therefore to assist
+ gdb and to create more self-contained core files we adjust l_name to
+ point at the newly allocated copy (which will get dumped) instead of
+ the ld.so rodata copy.
+
+ Furthermore, in case of explicit loader invocation, discard the
+ name of the main executable, to match the regular behavior, where
+ name of the executable is not known. */
+#ifdef SHARED
+ if (*realname != '\0' && (mode & __RTLD_OPENEXEC) == 0)
+#else
+ if (*realname != '\0')
+#endif
+ new->l_name = realname;
+ else
+ new->l_name = (char *) newname->name + libname_len - 1;
+
new->l_type = type;
+ /* If we set the bit now since we know it is never used we avoid
+ dirtying the cache line later. */
+ if ((GLRO(dl_debug_mask) & DL_DEBUG_UNUSED) == 0)
+ new->l_used = 1;
+ new->l_loader = loader;
+#if NO_TLS_OFFSET != 0
+ new->l_tls_offset = NO_TLS_OFFSET;
+#endif
+ new->l_ns = nsid;
- if (_dl_loaded == NULL)
+#ifdef SHARED
+ for (unsigned int cnt = 0; cnt < naudit; ++cnt)
{
- new->l_prev = new->l_next = NULL;
- _dl_loaded = new;
+ new->l_audit[cnt].cookie = (uintptr_t) new;
+ /* new->l_audit[cnt].bindflags = 0; */
}
+#endif
+
+ /* new->l_global = 0; We use calloc therefore not necessary. */
+
+ /* Use the 'l_scope_mem' array by default for the 'l_scope'
+ information. If we need more entries we will allocate a large
+ array dynamically. */
+ new->l_scope = new->l_scope_mem;
+ new->l_scope_max = sizeof (new->l_scope_mem) / sizeof (new->l_scope_mem[0]);
+
+ /* Counter for the scopes we have to handle. */
+ int idx = 0;
+
+ if (GL(dl_ns)[nsid]._ns_loaded != NULL)
+ /* Add the global scope. */
+ new->l_scope[idx++] = &GL(dl_ns)[nsid]._ns_loaded->l_searchlist;
+
+ /* If we have no loader the new object acts as it. */
+ if (loader == NULL)
+ loader = new;
else
+ /* Determine the local scope. */
+ while (loader->l_loader != NULL)
+ loader = loader->l_loader;
+
+ /* Insert the scope if it isn't the global scope we already added. */
+ if (idx == 0 || &loader->l_searchlist != new->l_scope[0])
{
- struct link_map *l = _dl_loaded;
- while (l->l_next)
- l = l->l_next;
- new->l_prev = l;
- new->l_next = NULL;
- l->l_next = new;
+ if ((mode & RTLD_DEEPBIND) != 0 && idx != 0)
+ {
+ new->l_scope[1] = new->l_scope[0];
+ idx = 0;
+ }
+
+ new->l_scope[idx] = &loader->l_searchlist;
+ }
+
+ new->l_local_scope[0] = &new->l_searchlist;
+
+ /* Determine the origin. If allocating the link map for the main
+ executable, the realname is not known and "". In this case, the
+ origin needs to be determined by other means. However, in case
+ of an explicit loader invocation, the pathname of the main
+ executable is known and needs to be processed here: From the
+ point of view of the kernel, the main executable is the
+ dynamic loader, and this would lead to a computation of the wrong
+ origin. */
+ if (realname[0] != '\0')
+ {
+ size_t realname_len = strlen (realname) + 1;
+ char *origin;
+ char *cp;
+
+ if (realname[0] == '/')
+ {
+ /* It is an absolute path. Use it. But we have to make a
+ copy since we strip out the trailing slash. */
+ cp = origin = (char *) malloc (realname_len);
+ if (origin == NULL)
+ {
+ origin = (char *) -1;
+ goto out;
+ }
+ }
+ else
+ {
+ size_t len = realname_len;
+ char *result = NULL;
+
+ /* Get the current directory name. */
+ origin = NULL;
+ do
+ {
+ char *new_origin;
+
+ len += 128;
+ new_origin = (char *) realloc (origin, len);
+ if (new_origin == NULL)
+ /* We exit the loop. Note that result == NULL. */
+ break;
+ origin = new_origin;
+ }
+ while ((result = __getcwd (origin, len - realname_len)) == NULL
+ && errno == ERANGE);
+
+ if (result == NULL)
+ {
+ /* We were not able to determine the current directory.
+ Note that free(origin) is OK if origin == NULL. */
+ free (origin);
+ origin = (char *) -1;
+ goto out;
+ }
+
+ /* Find the end of the path and see whether we have to add a
+ slash. We could use rawmemchr but this need not be
+ fast. */
+ cp = (strchr) (origin, '\0');
+ if (cp[-1] != '/')
+ *cp++ = '/';
+ }
+
+ /* Add the real file name. */
+ cp = __mempcpy (cp, realname, realname_len);
+
+ /* Now remove the filename and the slash. Leave the slash if
+ the name is something like "/foo". */
+ do
+ --cp;
+ while (*cp != '/');
+
+ if (cp == origin)
+ /* Keep the only slash which is the first character. */
+ ++cp;
+ *cp = '\0';
+
+ out:
+ new->l_origin = origin;
}
return new;