libdl: fix dlclose handling of symbol scope

Defer removal of the local scope of a dl-opened library after
all the destructors (of itself and related dependencies) are actually
get unloaded, otherwise any function registered via atexit()
won't be resolved.

Signed-off-by: Carmelo Amoroso <carmelo.amoroso@st.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Filippo Arcidiacono <filippo.arcidiacono@st.com>

diff --git a/ldso/libdl/libdl.c b/ldso/libdl/libdl.c
index 32afe1c..086a059 100644 (file)
--- a/ldso/libdl/libdl.c
+++ b/ldso/libdl/libdl.c
@@ -781,7 +781,9 @@ static int do_dlclose(void *vhandle, int need_fini)
        struct dyn_elf *handle;
        unsigned int end = 0, start = 0xffffffff;
        unsigned int i, j;
-       struct r_scope_elem *ls;
+       struct r_scope_elem *ls, *ls_next = NULL;
+       struct elf_resolve **handle_rlist;
+
 #if defined(USE_TLS) && USE_TLS
        bool any_tls = false;
        size_t tls_free_start = NO_TLS_OFFSET;
@@ -814,6 +816,19 @@ static int do_dlclose(void *vhandle, int need_fini)
                free(handle);
                return 0;
        }
+
+       /* Store the handle's local scope array for later removal */
+       handle_rlist = handle->dyn->symbol_scope.r_list;
+
+       /* Store references to the local scope entries for later removal */
+       for (ls = &_dl_loaded_modules->symbol_scope; ls && ls->next; ls = ls->next)
+               if (ls->next->r_list[0] == handle->dyn) {
+                       break;
+               }
+       /* ls points to the previous local symbol scope */
+       if(ls && ls->next)
+               ls_next = ls->next->next;
+
        /* OK, this is a valid handle - now close out the file */
        for (j = 0; j < handle->init_fini.nlist; ++j) {
                tpnt = handle->init_fini.init_fini[j];
@@ -975,16 +990,6 @@ static int do_dlclose(void *vhandle, int need_fini)
                                }
                        }
 
-                       if (handle->dyn == tpnt) {
-                               /* Unlink the local scope from global one */
-                               for (ls = &_dl_loaded_modules->symbol_scope; ls; ls = ls->next)
-                                       if (ls->next->r_list[0] == tpnt) {
-                                               _dl_if_debug_print("removing symbol_scope: %s\n", tpnt->libname);
-                                               break;
-                                       }
-                               ls->next = ls->next->next;
-                       }
-
                        /* Next, remove tpnt from the global symbol table list */
                        if (_dl_symbol_tables) {
                                if (_dl_symbol_tables->dyn == tpnt) {
@@ -1006,10 +1011,14 @@ static int do_dlclose(void *vhandle, int need_fini)
                                }
                        }
                        free(tpnt->libname);
-                       free(tpnt->symbol_scope.r_list);
                        free(tpnt);
                }
        }
+       /* Unlink and release the handle's local scope from global one */
+       if(ls)
+               ls->next = ls_next;
+       free(handle_rlist);
+
        for (rpnt1 = handle->next; rpnt1; rpnt1 = rpnt1_tmp) {
                rpnt1_tmp = rpnt1->next;
                free(rpnt1);