elf: Use RTLD_NODELETE is more places

* On dlopen dependencies for objects opened with RTLD_NODELETE
  (since it does not make sense to unload a dependency of a
   RTLD_NODELETE object);

* For the main map executable.

* For the main map DT_NEEDED dependencies.

* On __libc_unwind_link_get for libgcc_s.so (used for backtrace and
  unwind).

Checked on x86_64-linux-gnu.
This commit is contained in:
Adhemerval Zanella 2024-07-08 16:10:58 -03:00
parent e3b0b3484c
commit 4d2825a355
4 changed files with 10 additions and 6 deletions

View File

@ -636,7 +636,8 @@ dl_open_worker_begin (void *a)
/* Load that object's dependencies. */
_dl_map_object_deps (new, NULL, 0, 0,
mode & (__RTLD_DLOPEN | RTLD_DEEPBIND | __RTLD_AUDIT));
mode & (__RTLD_DLOPEN | RTLD_DEEPBIND | __RTLD_AUDIT
| RTLD_NODELETE));
/* So far, so good. Now check the versions. */
for (unsigned int i = 0; i < new->l_searchlist.r_nlist; ++i)

View File

@ -811,7 +811,7 @@ do_preload (const char *fname, struct link_map *main_map, const char *where)
args.str = fname;
args.loader = main_map;
args.mode = __RTLD_SECURE;
args.mode = __RTLD_SECURE | RTLD_NODELETE;
unsigned int old_nloaded = GL(dl_ns)[LM_ID_BASE]._ns_nloaded;
@ -1638,7 +1638,7 @@ dl_main (const ElfW(Phdr) *phdr,
/* Create a link_map for the executable itself.
This will be what dlopen on "" returns. */
main_map = _dl_new_object ((char *) "", "", lt_executable, NULL,
__RTLD_OPENEXEC, LM_ID_BASE);
__RTLD_OPENEXEC | RTLD_NODELETE, LM_ID_BASE);
assert (main_map != NULL);
main_map->l_phdr = phdr;
main_map->l_phnum = phnum;
@ -1966,7 +1966,7 @@ dl_main (const ElfW(Phdr) *phdr,
RTLD_TIMING_VAR (start);
rtld_timer_start (&start);
_dl_map_object_deps (main_map, preloads, npreloads,
state.mode == rtld_mode_trace, 0);
state.mode == rtld_mode_trace, RTLD_NODELETE);
rtld_timer_accum (&load_time, start);
}

View File

@ -50,6 +50,8 @@ extern char **__libc_argv attribute_hidden;
better error handling semantics for the library. */
#define __libc_dlopen(name) \
__libc_dlopen_mode (name, RTLD_NOW | __RTLD_DLOPEN)
#define __libc_dlopen_nodelete(name) \
__libc_dlopen_mode (name, RTLD_NODELETE | RTLD_NOW | __RTLD_DLOPEN)
extern void *__libc_dlopen_mode (const char *__name, int __mode)
attribute_hidden;
extern void *__libc_dlsym (void *__map, const char *__name)

View File

@ -48,7 +48,7 @@ __libc_unwind_link_get (void)
/* Initialize a copy of the data, so that we do not need about
unlocking in case the dynamic loader somehow triggers
unwinding. */
void *local_libgcc_handle = __libc_dlopen (LIBGCC_S_SO);
void *local_libgcc_handle = __libc_dlopen_nodelete (LIBGCC_S_SO);
if (local_libgcc_handle == NULL)
{
__libc_lock_unlock (lock);
@ -100,7 +100,8 @@ __libc_unwind_link_get (void)
__libc_lock_lock (lock);
if (atomic_load_relaxed (&global_libgcc_handle) != NULL)
/* This thread lost the race. Clean up. */
/* This thread lost the race. Drop the l_direct_opencount and issue
the debug log. */
__libc_dlclose (local_libgcc_handle);
else
{