Author: kib
Date: Mon Oct 7 08:19:30 2013
New Revision: 256101
URL: http://svnweb.freebsd.org/changeset/base/256101
Log:
Implement support for the interpose dso flag.
Requested by: bf
Reviewed by: kan
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Approved by: re (glebius)
Modified:
head/libexec/rtld-elf/rtld.c
head/libexec/rtld-elf/rtld.h
Modified: head/libexec/rtld-elf/rtld.c
==============================================================================
--- head/libexec/rtld-elf/rtld.c Mon Oct 7 08:14:58 2013
(r256100)
+++ head/libexec/rtld-elf/rtld.c Mon Oct 7 08:19:30 2013
(r256101)
@@ -116,6 +116,7 @@ static Objlist_Entry *objlist_find(Objli
static void objlist_init(Objlist *);
static void objlist_push_head(Objlist *, Obj_Entry *);
static void objlist_push_tail(Objlist *, Obj_Entry *);
+static void objlist_put_after(Objlist *, Obj_Entry *, Obj_Entry *);
static void objlist_remove(Objlist *, Obj_Entry *);
static void *path_enumerate(const char *, path_enum_proc, void *);
static int relocate_object_dag(Obj_Entry *root, bool bind_now,
@@ -323,6 +324,7 @@ _rtld(Elf_Addr *sp, func_ptr_type *exit_
Objlist_Entry *entry;
Obj_Entry *obj;
Obj_Entry **preload_tail;
+ Obj_Entry *last_interposer;
Objlist initlist;
RtldLockState lockstate;
char *library_path_rpath;
@@ -537,8 +539,14 @@ _rtld(Elf_Addr *sp, func_ptr_type *exit_
die();
/* Make a list of all objects loaded at startup. */
+ last_interposer = obj_main;
for (obj = obj_list; obj != NULL; obj = obj->next) {
- objlist_push_tail(&list_main, obj);
+ if (obj->z_interpose && obj != obj_main) {
+ objlist_put_after(&list_main, last_interposer, obj);
+ last_interposer = obj;
+ } else {
+ objlist_push_tail(&list_main, obj);
+ }
obj->refcount++;
}
@@ -1128,6 +1136,8 @@ digest_dynamic1(Obj_Entry *obj, int earl
obj->z_nodelete = true;
if (dynp->d_un.d_val & DF_1_LOADFLTR)
obj->z_loadfltr = true;
+ if (dynp->d_un.d_val & DF_1_INTERPOSE)
+ obj->z_interpose = true;
if (dynp->d_un.d_val & DF_1_NODEFLIB)
obj->z_nodeflib = true;
break;
@@ -1976,6 +1986,7 @@ static int
load_preload_objects(void)
{
char *p = ld_preload;
+ Obj_Entry *obj;
static const char delim[] = " \t:;";
if (p == NULL)
@@ -1988,8 +1999,10 @@ load_preload_objects(void)
savech = p[len];
p[len] = '\0';
- if (load_object(p, -1, NULL, 0) == NULL)
+ obj = load_object(p, -1, NULL, 0);
+ if (obj == NULL)
return -1; /* XXX - cleanup */
+ obj->z_interpose = true;
p[len] = savech;
p += len;
p += strspn(p, delim);
@@ -2378,6 +2391,23 @@ objlist_push_tail(Objlist *list, Obj_Ent
}
static void
+objlist_put_after(Objlist *list, Obj_Entry *listobj, Obj_Entry *obj)
+{
+ Objlist_Entry *elm, *listelm;
+
+ STAILQ_FOREACH(listelm, list, link) {
+ if (listelm->obj == listobj)
+ break;
+ }
+ elm = NEW(Objlist_Entry);
+ elm->obj = obj;
+ if (listelm != NULL)
+ STAILQ_INSERT_AFTER(list, listelm, elm, link);
+ else
+ STAILQ_INSERT_TAIL(list, elm, link);
+}
+
+static void
objlist_remove(Objlist *list, Obj_Entry *obj)
{
Objlist_Entry *elm;
Modified: head/libexec/rtld-elf/rtld.h
==============================================================================
--- head/libexec/rtld-elf/rtld.h Mon Oct 7 08:14:58 2013
(r256100)
+++ head/libexec/rtld-elf/rtld.h Mon Oct 7 08:19:30 2013
(r256101)
@@ -259,6 +259,7 @@ typedef struct Struct_Obj_Entry {
bool z_nodelete : 1; /* Do not unload the object and dependencies */
bool z_noopen : 1; /* Do not load on dlopen */
bool z_loadfltr : 1; /* Immediately load filtees */
+ bool z_interpose : 1; /* Interpose all objects but main */
bool z_nodeflib : 1; /* Don't search default library path */
bool ref_nodel : 1; /* Refcount increased to prevent
dlclose */
bool init_scanned: 1; /* Object is already on init list. */
_______________________________________________
svn-src-all@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/svn-src-all
To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
