Fix known issues which blow up the process after dlopen("libthr.so")

(or loading a dso linked to libthr.so into process which was not
linked against threading library).

MFC r276630:
Remove interposing, fix malloc, reinstall signal handlers wrappers on
libthr load.

MFC r276681:
Avoid calling internal libc function through PLT or accessing data
though GOT.

MFC r277032:
Reduce the size of the interposing table and amount of
cancellation-handling code in the libthr.

MFC note:
r276646 ("do not erronously export 'openat' symbol from rtld") is not
applicable to stable/10 yet, since PATHFDS support was not merged.

1 files changed, 2 insertions, 4 deletions

diff --git a/lib/libthr/thread/thr_fork.c b/lib/libthr/thread/thr_fork.c
index fc87688..7dc8ca8 100644
--- a/lib/libthr/thread/thr_fork.c
+++ b/lib/libthr/thread/thr_fork.c
@@ -128,12 +128,10 @@ __pthread_cxa_finalize(struct dl_phdr_info *phdr_info)
 	_thr_sigact_unload(phdr_info);
 }
 
-__weak_reference(_fork, fork);
-
-pid_t _fork(void);
+__weak_reference(__thr_fork, _fork);
 
 pid_t
-_fork(void)
+__thr_fork(void)
 {
 	struct pthread *curthread;
 	struct pthread_atfork *af;