system/freebsd-src
system/freebsd-src
1
0
Fork 0
mirror of https://github.com/freebsd/freebsd-src synced 2024-07-23 19:28:36 +00:00
Code Issues Actions 2 Packages Projects Releases Wiki Activity

rtld: fix dlopen() for an object that is already mapped but not yet initialized

Browse source 
For instance, dso might be mapped as needed but not yet initialized from
the other subtree of needed objects, while current object' constructor
does dlopen() for the dso.  Right now rtld does relocations and other
processing based on the arrival of new objects in the global list, which
is not happens there.  Directly check for the initialization state of
the object, for which we would return the handle.

One practical use case of this support is e.g. dlopen("libthr.so",
RTLD_NOLOAD) by libraries that are threading-aware but happy to live
with libc pthread shims if the program is not multithreaded.

Reviewed by:	tijl
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
This commit is contained in:
Konstantin Belousov 2023-07-14 16:38:03 +03:00
parent ad056b5d35
commit 1005d3d053
1 changed files with 3 additions and 5 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

8
libexec/rtld-elf/rtld.c
View file

@ -3714,7 +3714,6 @@ static Obj_Entry *
dlopen_object(const char *name, int fd, Obj_Entry *refobj, int lo_flags,
int mode, RtldLockState *lockstate)
{
Obj_Entry *old_obj_tail;
Obj_Entry *obj;
Objlist initlist;
RtldLockState mlockstate;
@ -3731,7 +3730,6 @@ dlopen_object(const char *name, int fd, Obj_Entry *refobj, int lo_flags,
}
GDB_STATE(RT_ADD,NULL);
old_obj_tail = globallist_curr(TAILQ_LAST(&obj_list, obj_entry_q));
obj = NULL;
if (name == NULL && fd == -1) {
obj = obj_main;
@ -3744,9 +3742,9 @@ dlopen_object(const char *name, int fd, Obj_Entry *refobj, int lo_flags,
obj->dl_refcount++;
if (mode & RTLD_GLOBAL && objlist_find(&list_global, obj) == NULL)
objlist_push_tail(&list_global, obj);
if (globallist_next(old_obj_tail) != NULL) {
/* We loaded something new. */
assert(globallist_next(old_obj_tail) == obj);
if (!obj->init_done) {
/* We loaded something new and have to init something. */
if ((lo_flags & RTLD_LO_DEEPBIND) != 0)
obj->symbolic = true;
result = 0;