/* Load a shared object at runtime, relocate it, and run its initializer.
- Copyright (C) 1996-2007, 2009, 2010, 2011 Free Software Foundation, Inc.
+ Copyright (C) 1996-2015 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
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. */
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
#include <assert.h>
#include <dlfcn.h>
#include <sys/param.h>
#include <bits/libc-lock.h>
#include <ldsodefs.h>
-#include <bp-sym.h>
#include <caller.h>
#include <sysdep-cancel.h>
#include <tls.h>
+#include <stap-probe.h>
+#include <atomic.h>
#include <dl-dst.h>
-extern ElfW(Addr) _dl_sysdep_start (void **start_argptr,
- void (*dl_main) (const ElfW(Phdr) *phdr,
- ElfW(Word) phnum,
- ElfW(Addr) *user_entry,
- ElfW(auxv_t) *auxv));
-weak_extern (BP_SYM (_dl_sysdep_start))
-
extern int __libc_multiple_libcs; /* Defined in init-first.c. */
-/* We must be carefull not to leave us in an inconsistent state. Thus we
+/* We must be careful not to leave us in an inconsistent state. Thus we
catch any error and re-raise it after cleaning up. */
struct dl_open_args
int mode;
/* This is the caller of the dlopen() function. */
const void *caller_dlopen;
- /* This is the caller if _dl_open(). */
+ /* This is the caller of _dl_open(). */
const void *caller_dl_open;
struct link_map *map;
/* Namespace ID. */
{
map->l_global = 1;
ns->_ns_main_searchlist->r_list[new_nlist++] = map;
+
+ /* We modify the global scope. Report this. */
+ if (__glibc_unlikely (GLRO(dl_debug_mask) & DL_DEBUG_SCOPES))
+ _dl_debug_printf ("\nadd %s [%lu] to global scope\n",
+ map->l_name, map->l_ns);
}
}
atomic_write_barrier ();
return 0;
}
+/* Search link maps in all namespaces for the DSO that contains the object at
+ address ADDR. Returns the pointer to the link map of the matching DSO, or
+ NULL if a match is not found. */
+struct link_map *
+internal_function
+_dl_find_dso_for_object (const ElfW(Addr) addr)
+{
+ struct link_map *l;
+
+ /* Find the highest-addressed object that ADDR is not below. */
+ for (Lmid_t ns = 0; ns < GL(dl_nns); ++ns)
+ for (l = GL(dl_ns)[ns]._ns_loaded; l != NULL; l = l->l_next)
+ if (addr >= l->l_map_start && addr < l->l_map_end
+ && (l->l_contiguous
+ || _dl_addr_inside_object (l, (ElfW(Addr)) addr)))
+ {
+ assert (ns == l->l_ns);
+ return l;
+ }
+ return NULL;
+}
+rtld_hidden_def (_dl_find_dso_for_object);
+
static void
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 < GL(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
- && (l->l_contiguous
- || _dl_addr_inside_object (l, (ElfW(Addr)) caller_dlopen)))
- {
- assert (ns == l->l_ns);
- call_map = l;
- goto found_caller;
- }
+ struct link_map *l = _dl_find_dso_for_object ((ElfW(Addr)) caller_dlopen);
+
+ if (l)
+ call_map = l;
- found_caller:
if (args->nsid == __LM_ID_CALLER)
- {
-#ifndef SHARED
- /* In statically linked apps there might be no loaded object. */
- if (call_map == NULL)
- args->nsid = LM_ID_BASE;
- else
-#endif
- args->nsid = call_map->l_ns;
- }
+ args->nsid = call_map->l_ns;
}
- assert (_dl_debug_initialize (0, args->nsid)->r_state == RT_CONSISTENT);
+ /* One might be tempted to assert that we are RT_CONSISTENT at this point, but that
+ may not be true if this is a recursive call to dlopen. */
+ _dl_debug_initialize (0, args->nsid);
/* Load the named object. */
struct link_map *new;
return;
}
- if (__builtin_expect (mode & __RTLD_SPROF, 0))
+ if (__glibc_unlikely (mode & __RTLD_SPROF))
/* This happens only if we load a DSO for 'sprof'. */
return;
++new->l_direct_opencount;
/* It was already open. */
- if (__builtin_expect (new->l_searchlist.r_list != NULL, 0))
+ if (__glibc_unlikely (new->l_searchlist.r_list != NULL))
{
/* Let the user know about the opencount. */
- if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_FILES, 0))
+ if (__glibc_unlikely (GLRO(dl_debug_mask) & DL_DEBUG_FILES))
_dl_debug_printf ("opening file=%s [%lu]; direct_opencount=%u\n\n",
new->l_name, new->l_ns, new->l_direct_opencount);
#ifdef SHARED
/* Auditing checkpoint: we have added all objects. */
- if (__builtin_expect (GLRO(dl_naudit) > 0, 0))
+ if (__glibc_unlikely (GLRO(dl_naudit) > 0))
{
struct link_map *head = GL(dl_ns)[new->l_ns]._ns_loaded;
/* Do not call the functions for any auditing object. */
struct r_debug *r = _dl_debug_initialize (0, args->nsid);
r->r_state = RT_CONSISTENT;
_dl_debug_state ();
+ LIBC_PROBE (map_complete, 3, args->nsid, r, new);
+
+ /* Print scope information. */
+ if (__glibc_unlikely (GLRO(dl_debug_mask) & DL_DEBUG_SCOPES))
+ _dl_show_scope (new, 0);
/* Only do lazy relocation if `LD_BIND_NOW' is not set. */
int reloc_mode = mode & __RTLD_AUDIT;
if (GLRO(dl_lazy))
reloc_mode |= mode & RTLD_LAZY;
- /* Relocate the objects loaded. We do this in reverse order so that copy
- relocs of earlier objects overwrite the data written by later objects. */
-
+ /* Sort the objects by dependency for the relocation process. This
+ allows IFUNC relocations to work and it also means copy
+ relocation of dependencies are if necessary overwritten. */
+ size_t nmaps = 0;
struct link_map *l = new;
- while (l->l_next)
- l = l->l_next;
- while (1)
+ do
{
if (! l->l_real->l_relocated)
+ ++nmaps;
+ l = l->l_next;
+ }
+ while (l != NULL);
+ struct link_map *maps[nmaps];
+ nmaps = 0;
+ l = new;
+ do
+ {
+ if (! l->l_real->l_relocated)
+ maps[nmaps++] = l;
+ l = l->l_next;
+ }
+ while (l != NULL);
+ if (nmaps > 1)
+ {
+ uint16_t seen[nmaps];
+ memset (seen, '\0', sizeof (seen));
+ size_t i = 0;
+ while (1)
{
-#ifdef SHARED
- if (__builtin_expect (GLRO(dl_profile) != NULL, 0))
+ ++seen[i];
+ struct link_map *thisp = maps[i];
+
+ /* Find the last object in the list for which the current one is
+ a dependency and move the current object behind the object
+ with the dependency. */
+ size_t k = nmaps - 1;
+ while (k > i)
{
- /* If this here is the shared object which we want to profile
- make sure the profile is started. We can find out whether
- this is necessary or not by observing the `_dl_profile_map'
- variable. If was NULL but is not NULL afterwars we must
- start the profiling. */
- struct link_map *old_profile_map = GL(dl_profile_map);
+ struct link_map **runp = maps[k]->l_initfini;
+ if (runp != NULL)
+ /* Look through the dependencies of the object. */
+ while (*runp != NULL)
+ if (__glibc_unlikely (*runp++ == thisp))
+ {
+ /* Move the current object to the back past the last
+ object with it as the dependency. */
+ memmove (&maps[i], &maps[i + 1],
+ (k - i) * sizeof (maps[0]));
+ maps[k] = thisp;
+
+ if (seen[i + 1] > nmaps - i)
+ {
+ ++i;
+ goto next_clear;
+ }
+
+ uint16_t this_seen = seen[i];
+ memmove (&seen[i], &seen[i + 1],
+ (k - i) * sizeof (seen[0]));
+ seen[k] = this_seen;
+
+ goto next;
+ }
+
+ --k;
+ }
- _dl_relocate_object (l, l->l_scope, reloc_mode | RTLD_LAZY, 1);
+ if (++i == nmaps)
+ break;
+ next_clear:
+ memset (&seen[i], 0, (nmaps - i) * sizeof (seen[0]));
+ next:;
+ }
+ }
- if (old_profile_map == NULL && GL(dl_profile_map) != NULL)
- {
- /* We must prepare the profiling. */
- _dl_start_profile ();
+ int relocation_in_progress = 0;
- /* Prevent unloading the object. */
- GL(dl_profile_map)->l_flags_1 |= DF_1_NODELETE;
- }
- }
- else
-#endif
- _dl_relocate_object (l, l->l_scope, reloc_mode, 0);
+ for (size_t i = nmaps; i-- > 0; )
+ {
+ l = maps[i];
+
+ if (! relocation_in_progress)
+ {
+ /* Notify the debugger that relocations are about to happen. */
+ LIBC_PROBE (reloc_start, 2, args->nsid, r);
+ relocation_in_progress = 1;
}
- if (l == new)
- break;
- l = l->l_prev;
+#ifdef SHARED
+ if (__glibc_unlikely (GLRO(dl_profile) != NULL))
+ {
+ /* If this here is the shared object which we want to profile
+ make sure the profile is started. We can find out whether
+ this is necessary or not by observing the `_dl_profile_map'
+ variable. If it was NULL but is not NULL afterwards we must
+ start the profiling. */
+ struct link_map *old_profile_map = GL(dl_profile_map);
+
+ _dl_relocate_object (l, l->l_scope, reloc_mode | RTLD_LAZY, 1);
+
+ if (old_profile_map == NULL && GL(dl_profile_map) != NULL)
+ {
+ /* We must prepare the profiling. */
+ _dl_start_profile ();
+
+ /* Prevent unloading the object. */
+ GL(dl_profile_map)->l_flags_1 |= DF_1_NODELETE;
+ }
+ }
+ else
+#endif
+ _dl_relocate_object (l, l->l_scope, reloc_mode, 0);
}
/* If the file is not loaded now as a dependency, add the search
for (unsigned int i = 0; i < new->l_searchlist.r_nlist; ++i)
{
struct link_map *imap = new->l_searchlist.r_list[i];
+ int from_scope = 0;
/* If the initializer has been called already, the object has
not been loaded here and now. */
/* Avoid duplicates. */
continue;
- if (__builtin_expect (cnt + 1 >= imap->l_scope_max, 0))
+ if (__glibc_unlikely (cnt + 1 >= imap->l_scope_max))
{
/* The 'r_scope' array is too small. Allocate a new one
dynamically. */
atomic_write_barrier ();
imap->l_scope[cnt] = &new->l_searchlist;
- /* Print scope information. */
- if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_SCOPES, 0))
- _dl_show_scope (imap);
+ /* Print only new scope information. */
+ from_scope = cnt;
}
/* Only add TLS memory if this object is loaded now and
therefore is not yet initialized. */
/* We have to bump the generation counter. */
any_tls = true;
}
+
+ /* Print scope information. */
+ if (__glibc_unlikely (GLRO(dl_debug_mask) & DL_DEBUG_SCOPES))
+ _dl_show_scope (imap, from_scope);
}
/* Bump the generation number if necessary. */
TLS generation counter wrapped! Please report this."));
/* We need a second pass for static tls data, because _dl_update_slotinfo
- must not be run while calls to _dl_add_to_slotinfo are still pending. */
+ must not be run while calls to _dl_add_to_slotinfo are still pending. */
for (unsigned int i = first_static_tls; i < new->l_searchlist.r_nlist; ++i)
{
struct link_map *imap = new->l_searchlist.r_list[i];
{
/* For static TLS we have to allocate the memory here and
now. This includes allocating memory in the DTV. But we
- cannot change any DTV other than our own. So, if we
+ cannot change any DTV other than our own. So, if we
cannot guarantee that there is room in the DTV we don't
even try it and fail the load.
}
}
+ /* Notify the debugger all new objects have been relocated. */
+ if (relocation_in_progress)
+ LIBC_PROBE (reloc_complete, 3, args->nsid, r, new);
+
+#ifndef SHARED
+ DL_STATIC_INIT (new);
+#endif
+
/* Run the initializer functions of new objects. */
_dl_init (new, args->argc, args->argv, args->env);
/* Mark the object as not deletable if the RTLD_NODELETE flags was
passed. */
- if (__builtin_expect (mode & RTLD_NODELETE, 0))
+ if (__glibc_unlikely (mode & RTLD_NODELETE))
new->l_flags_1 |= DF_1_NODELETE;
#ifndef SHARED
#endif
/* Let the user know about the opencount. */
- if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_FILES, 0))
+ if (__glibc_unlikely (GLRO(dl_debug_mask) & DL_DEBUG_FILES))
_dl_debug_printf ("opening file=%s [%lu]; direct_opencount=%u\n\n",
new->l_name, new->l_ns, new->l_direct_opencount);
-
- /* Print scope information. */
- if (__builtin_expect (GLRO(dl_debug_mask) & DL_DEBUG_SCOPES, 0))
- _dl_show_scope (new);
}
/* Make sure we are alone. */
__rtld_lock_lock_recursive (GL(dl_load_lock));
- if (__builtin_expect (nsid == LM_ID_NEWLM, 0))
+ if (__glibc_unlikely (nsid == LM_ID_NEWLM))
{
/* Find a new namespace. */
for (nsid = 1; DL_NNS > 1 && nsid < GL(dl_nns); ++nsid)
if (GL(dl_ns)[nsid]._ns_loaded == NULL)
break;
- if (__builtin_expect (nsid == DL_NNS, 0))
+ if (__glibc_unlikely (nsid == DL_NNS))
{
/* No more namespace available. */
__rtld_lock_unlock_recursive (GL(dl_load_lock));
|| GL(dl_ns)[nsid]._ns_loaded->l_auditing))
_dl_signal_error (EINVAL, file, NULL,
N_("invalid target namespace in dlmopen()"));
-#ifndef SHARED
- else if ((nsid == LM_ID_BASE || nsid == __LM_ID_CALLER)
- && GL(dl_ns)[LM_ID_BASE]._ns_loaded == NULL
- && GL(dl_nns) == 0)
- GL(dl_nns) = 1;
-#endif
struct dl_open_args args;
args.file = file;
int errcode = _dl_catch_error (&objname, &errstring, &malloced,
dl_open_worker, &args);
-#ifndef MAP_COPY
- /* We must munmap() the cache file. */
+#if defined USE_LDCONFIG && !defined MAP_COPY
+ /* We must unmap the cache file. */
_dl_unload_cache ();
#endif
/* See if an error occurred during loading. */
- if (__builtin_expect (errstring != NULL, 0))
+ if (__glibc_unlikely (errstring != NULL))
{
/* Remove the object from memory. It may be in an inconsistent
state if relocation failed, for example. */
/* Release the lock. */
__rtld_lock_unlock_recursive (GL(dl_load_lock));
-#ifndef SHARED
- DL_STATIC_INIT (args.map);
-#endif
-
return args.map;
}
void
-_dl_show_scope (struct link_map *l)
+_dl_show_scope (struct link_map *l, int from)
{
_dl_debug_printf ("object=%s [%lu]\n",
- *l->l_name ? l->l_name : rtld_progname, l->l_ns);
+ DSO_FILENAME (l->l_name), l->l_ns);
if (l->l_scope != NULL)
- for (int scope_cnt = 0; l->l_scope[scope_cnt] != NULL; ++scope_cnt)
+ for (int scope_cnt = from; l->l_scope[scope_cnt] != NULL; ++scope_cnt)
{
- char numbuf[2];
- unsigned int cnt;
-
- numbuf[0] = '0' + scope_cnt;
- numbuf[1] = '\0';
- _dl_debug_printf (" scope %s:", numbuf);
+ _dl_debug_printf (" scope %u:", scope_cnt);
- for (cnt = 0; cnt < l->l_scope[scope_cnt]->r_nlist; ++cnt)
+ for (unsigned int cnt = 0; cnt < l->l_scope[scope_cnt]->r_nlist; ++cnt)
if (*l->l_scope[scope_cnt]->r_list[cnt]->l_name)
_dl_debug_printf_c (" %s",
l->l_scope[scope_cnt]->r_list[cnt]->l_name);
else
- _dl_debug_printf_c (" %s", rtld_progname);
+ _dl_debug_printf_c (" %s", RTLD_PROGNAME);
_dl_debug_printf_c ("\n");
}
+ else
+ _dl_debug_printf (" no scope\n");
_dl_debug_printf ("\n");
}
-#ifdef IS_IN_rtld
+#if IS_IN (rtld)
/* Return non-zero if ADDR lies within one of L's segments. */
int
internal_function
projects / platform / upstream / glibc.git / blobdiff