diff options
| -rw-r--r-- | ChangeLog | 13 | ||||
| -rw-r--r-- | elf/dl-close.c | 5 | ||||
| -rw-r--r-- | elf/dl-iteratephdr.c | 8 | ||||
| -rw-r--r-- | elf/dl-load.c | 3 | ||||
| -rw-r--r-- | elf/dl-object.c | 5 | ||||
| -rw-r--r-- | elf/dl-support.c | 4 | ||||
| -rw-r--r-- | elf/rtld.c | 1 | ||||
| -rw-r--r-- | sysdeps/generic/ldsodefs.h | 4 |
8 files changed, 39 insertions, 4 deletions
@@ -1,3 +1,16 @@ +2010-02-02 Andreas Schwab <schwab@redhat.com> + + * sysdeps/generic/ldsodefs.h (struct rtld_global): Add + _dl_load_write_lock. + * elf/rtld.c (_rtld_global): Initialize it. + * elf/dl-support.c (_dl_load_write_lock): Define . + * elf/dl-close.c (_dl_close_worker): Lock GL(dl_load_write_lock) + when modifying the list of loaded objects. + * elf/dl-load.c (lose): Likewise. + * elf/dl-object.c (_dl_new_object): Likewise. + * elf/dl-iteratephdr.c (__dl_iterate_phdr): Lock + GL(dl_load_write_lock) instead of GL(dl_load_lock). + 2010-05-03 Ulrich Drepper <drepper@redhat.com> * elf/dl-iteratephdr.c (__dl_iterate_phdr): Remove unnecessary diff --git a/elf/dl-close.c b/elf/dl-close.c index b73a7adb1a..700e765c3c 100644 --- a/elf/dl-close.c +++ b/elf/dl-close.c @@ -507,6 +507,9 @@ _dl_close_worker (struct link_map *map) size_t tls_free_end; tls_free_start = tls_free_end = NO_TLS_OFFSET; + /* We modify the list of loaded objects. */ + __rtld_lock_lock_recursive (GL(dl_load_write_lock)); + /* Check each element of the search list to see if all references to it are gone. */ for (unsigned int i = first_loaded; i < nloaded; ++i) @@ -665,6 +668,8 @@ _dl_close_worker (struct link_map *map) } } + __rtld_lock_unlock_recursive (GL(dl_load_write_lock)); + /* If we removed any object which uses TLS bump the generation counter. */ if (any_tls) { diff --git a/elf/dl-iteratephdr.c b/elf/dl-iteratephdr.c index 44864c1b7a..5f1c20d755 100644 --- a/elf/dl-iteratephdr.c +++ b/elf/dl-iteratephdr.c @@ -26,7 +26,7 @@ static void cancel_handler (void *arg __attribute__((unused))) { - __rtld_lock_unlock_recursive (GL(dl_load_lock)); + __rtld_lock_unlock_recursive (GL(dl_load_write_lock)); } hidden_proto (__dl_iterate_phdr) @@ -38,8 +38,8 @@ __dl_iterate_phdr (int (*callback) (struct dl_phdr_info *info, struct dl_phdr_info info; int ret = 0; - /* Make sure we are alone. */ - __rtld_lock_lock_recursive (GL(dl_load_lock)); + /* Make sure nobody modifies the list of loaded objects. */ + __rtld_lock_lock_recursive (GL(dl_load_write_lock)); __libc_cleanup_push (cancel_handler, 0); /* We have to determine the namespace of the caller since this determines @@ -79,7 +79,7 @@ __dl_iterate_phdr (int (*callback) (struct dl_phdr_info *info, /* Release the lock. */ __libc_cleanup_pop (0); - __rtld_lock_unlock_recursive (GL(dl_load_lock)); + __rtld_lock_unlock_recursive (GL(dl_load_write_lock)); return ret; } diff --git a/elf/dl-load.c b/elf/dl-load.c index d8f9131dd6..0adddf5aaa 100644 --- a/elf/dl-load.c +++ b/elf/dl-load.c @@ -803,6 +803,8 @@ lose (int code, int fd, const char *name, char *realname, struct link_map *l, (void) __close (fd); if (l != NULL) { + /* We modify the list of loaded objects. */ + __rtld_lock_lock_recursive (GL(dl_load_write_lock)); /* Remove the stillborn object from the list and free it. */ assert (l->l_next == NULL); if (l->l_prev == NULL) @@ -813,6 +815,7 @@ lose (int code, int fd, const char *name, char *realname, struct link_map *l, l->l_prev->l_next = NULL; --GL(dl_ns)[l->l_ns]._ns_nloaded; free (l); + __rtld_lock_unlock_recursive (GL(dl_load_write_lock)); } free (realname); diff --git a/elf/dl-object.c b/elf/dl-object.c index 788e2c07b9..22a163560b 100644 --- a/elf/dl-object.c +++ b/elf/dl-object.c @@ -93,6 +93,9 @@ _dl_new_object (char *realname, const char *libname, int type, new->l_scope = new->l_scope_mem; new->l_scope_max = sizeof (new->l_scope_mem) / sizeof (new->l_scope_mem[0]); + /* We modify the list of loaded objects. */ + __rtld_lock_lock_recursive (GL(dl_load_write_lock)); + /* Counter for the scopes we have to handle. */ idx = 0; @@ -114,6 +117,8 @@ _dl_new_object (char *realname, const char *libname, int type, new->l_serial = GL(dl_load_adds); ++GL(dl_load_adds); + __rtld_lock_unlock_recursive (GL(dl_load_write_lock)); + /* If we have no loader the new object acts as it. */ if (loader == NULL) loader = new; diff --git a/elf/dl-support.c b/elf/dl-support.c index 65b25750de..f94d2c4c6e 100644 --- a/elf/dl-support.c +++ b/elf/dl-support.c @@ -166,6 +166,10 @@ const ElfW(Ehdr) *_dl_sysinfo_dso; the loaded object might as well require a call to this function. At this time it is not anymore a problem to modify the tables. */ __rtld_lock_define_initialized_recursive (, _dl_load_lock) +/* This lock is used to keep __dl_iterate_phdr from inspecting the + list of loaded objects while an object is added to or removed from + that list. */ +__rtld_lock_define_initialized_recursive (, _dl_load_write_lock) #ifdef HAVE_AUX_VECTOR diff --git a/elf/rtld.c b/elf/rtld.c index e26b2b9e1b..90f3ff126e 100644 --- a/elf/rtld.c +++ b/elf/rtld.c @@ -126,6 +126,7 @@ struct rtld_global _rtld_global = ._dl_stack_flags = PF_R|PF_W|PF_X, #ifdef _LIBC_REENTRANT ._dl_load_lock = _RTLD_LOCK_RECURSIVE_INITIALIZER, + ._dl_load_write_lock = _RTLD_LOCK_RECURSIVE_INITIALIZER, #endif ._dl_nns = 1, ._dl_ns = diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h index a14e8af92f..fcc943bce3 100644 --- a/sysdeps/generic/ldsodefs.h +++ b/sysdeps/generic/ldsodefs.h @@ -416,6 +416,10 @@ struct rtld_global the loaded object might as well require a call to this function. At this time it is not anymore a problem to modify the tables. */ __rtld_lock_define_recursive (EXTERN, _dl_load_lock) + /* This lock is used to keep __dl_iterate_phdr from inspecting the + list of loaded objects while an object is added to or removed + from that list. */ + __rtld_lock_define_recursive (EXTERN, _dl_load_write_lock) /* Incremented whenever something may have been added to dl_loaded. */ EXTERN unsigned long long _dl_load_adds; |