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.

12 files changed, 103 insertions, 73 deletions

diff --git a/lib/libc/gen/Makefile.inc b/lib/libc/gen/Makefile.inc
index 1b5222e..9bbf049 100644
--- a/lib/libc/gen/Makefile.inc
+++ b/lib/libc/gen/Makefile.inc
@@ -5,6 +5,7 @@
 .PATH: ${.CURDIR}/${LIBC_ARCH}/gen ${.CURDIR}/gen
 
 SRCS+=	__getosreldate.c \
+	__pthread_mutex_init_calloc_cb_stub.c \
 	__xuname.c \
 	_once_stub.c \
 	_pthread_stubs.c \
diff --git a/lib/libc/gen/Symbol.map b/lib/libc/gen/Symbol.map
index 5b20ebd..8dd9a05 100644
--- a/lib/libc/gen/Symbol.map
+++ b/lib/libc/gen/Symbol.map
@@ -529,6 +529,8 @@ FBSDprivate_1.0 {
 	_libc_sem_post_compat;
 	_libc_sem_getvalue_compat;
 
+	__libc_tcdrain;
+
 	__elf_aux_vector;
 	__pthread_map_stacks_exec;
 	__fillcontextx;
diff --git a/lib/libc/gen/__pthread_mutex_init_calloc_cb_stub.c b/lib/libc/gen/__pthread_mutex_init_calloc_cb_stub.c
new file mode 100644
index 0000000..1c566ec
--- /dev/null
+++ b/lib/libc/gen/__pthread_mutex_init_calloc_cb_stub.c
@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2014 The FreeBSD Foundation.
+ * All rights reserved.
+ *
+ * Portions of this software were developed by Konstantin Belousov
+ * under sponsorship from the FreeBSD Foundation.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice(s), this list of conditions and the following disclaimer as
+ *    the first lines of this file unmodified other than the possible
+ *    addition of one or more copyright notices.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice(s), this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+ * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+ * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <pthread.h>
+#include "libc_private.h"
+
+int
+_pthread_mutex_init_calloc_cb_stub(pthread_mutex_t *mutex,
+    void *(calloc_cb)(size_t, size_t))
+{
+
+	return (0);
+}
diff --git a/lib/libc/gen/pause.c b/lib/libc/gen/pause.c
index 51706cf..ef48c1c 100644
--- a/lib/libc/gen/pause.c
+++ b/lib/libc/gen/pause.c
@@ -33,10 +33,10 @@ static char sccsid[] = "@(#)pause.c	8.1 (Berkeley) 6/4/93";
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
-#include "namespace.h"
 #include <signal.h>
 #include <unistd.h>
-#include "un-namespace.h"
+
+#include "libc_private.h"
 
 /*
  * Backwards compatible pause.
@@ -46,9 +46,10 @@ __pause(void)
 {
 	sigset_t oset;
 
-	if (_sigprocmask(SIG_BLOCK, NULL, &oset) == -1)
+	if (sigprocmask(SIG_BLOCK, NULL, &oset) == -1)
 		return (-1);
-	return (_sigsuspend(&oset));
+	return (sigsuspend(&oset));
 }
+
 __weak_reference(__pause, pause);
 __weak_reference(__pause, _pause);
diff --git a/lib/libc/gen/raise.c b/lib/libc/gen/raise.c
index b3d0aae..994fea5 100644
--- a/lib/libc/gen/raise.c
+++ b/lib/libc/gen/raise.c
@@ -36,11 +36,17 @@ __FBSDID("$FreeBSD$");
 #include <signal.h>
 #include <unistd.h>
 
+#include "libc_private.h"
+
 __weak_reference(__raise, raise);
 __weak_reference(__raise, _raise);
 
 int
 __raise(int s)
 {
-	return(kill(getpid(), s));
+	long id;
+
+	if (__sys_thr_self(&id) == -1)
+		return (-1);
+	return (__sys_thr_kill(id, s));
 }
diff --git a/lib/libc/gen/sleep.c b/lib/libc/gen/sleep.c
index b807c2d..6bb4ecd 100644
--- a/lib/libc/gen/sleep.c
+++ b/lib/libc/gen/sleep.c
@@ -40,6 +40,8 @@ __FBSDID("$FreeBSD$");
 #include <unistd.h>
 #include "un-namespace.h"
 
+#include "libc_private.h"
+
 unsigned int
 __sleep(unsigned int seconds)
 {
@@ -55,12 +57,14 @@ __sleep(unsigned int seconds)
 
 	time_to_sleep.tv_sec = seconds;
 	time_to_sleep.tv_nsec = 0;
-	if (_nanosleep(&time_to_sleep, &time_remaining) != -1)
+	if (((int (*)(const struct timespec *, struct timespec *))
+	    __libc_interposing[INTERPOS_nanosleep])(
+	    &time_to_sleep, &time_remaining) != -1)
 		return (0);
 	if (errno != EINTR)
 		return (seconds);		/* best guess */
 	return (time_remaining.tv_sec +
-		(time_remaining.tv_nsec != 0)); /* round up */
+	    (time_remaining.tv_nsec != 0)); /* round up */
 }
 
 __weak_reference(__sleep, sleep);
diff --git a/lib/libc/gen/swapcontext.c b/lib/libc/gen/swapcontext.c
deleted file mode 100644
index c34cb23..0000000
--- a/lib/libc/gen/swapcontext.c
+++ /dev/null
@@ -1,55 +0,0 @@
-/*
- * Copyright (c) 2001 Daniel M. Eischen <deischen@freebsd.org>
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Neither the name of the author nor the names of its contributors
- *    may be used to endorse or promote products derived from this software
- *    without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
-
-#include <sys/cdefs.h>
-__FBSDID("$FreeBSD$");
-
-#include <sys/param.h>
-#include <sys/signal.h>
-#include <sys/ucontext.h>
-
-#include <errno.h>
-#include <stddef.h>
-
-__weak_reference(__swapcontext, swapcontext);
-
-int
-__swapcontext(ucontext_t *oucp, const ucontext_t *ucp)
-{
-	int ret;
-
-	if ((oucp == NULL) || (ucp == NULL)) {
-		errno = EINVAL;
-		return (-1);
-	}
-	oucp->uc_flags &= ~UCF_SWAPPED;
-	ret = getcontext(oucp);
-	if ((ret == 0) && !(oucp->uc_flags & UCF_SWAPPED)) {
-		oucp->uc_flags |= UCF_SWAPPED;
-		ret = setcontext(ucp);
-	}
-	return (ret);
-}
diff --git a/lib/libc/gen/termios.c b/lib/libc/gen/termios.c
index 7e9f169..f8b7354 100644
--- a/lib/libc/gen/termios.c
+++ b/lib/libc/gen/termios.c
@@ -46,6 +46,8 @@ __FBSDID("$FreeBSD$");
 #include <unistd.h>
 #include "un-namespace.h"
 
+#include "libc_private.h"
+
 int
 tcgetattr(int fd, struct termios *t)
 {
@@ -208,13 +210,23 @@ tcsendbreak(int fd, int len __unused)
 }
 
 int
-__tcdrain(int fd)
+__libc_tcdrain(int fd)
 {
+
 	return (_ioctl(fd, TIOCDRAIN, 0));
 }
 
-__weak_reference(__tcdrain, tcdrain);
-__weak_reference(__tcdrain, _tcdrain);
+#pragma weak tcdrain
+int
+tcdrain(int fd)
+{
+
+	return (((int (*)(int))
+	    __libc_interposing[INTERPOS_tcdrain])(fd));
+}
+
+__weak_reference(__libc_tcdrain, __tcdrain);
+__weak_reference(__libc_tcdrain, _tcdrain);
 
 int
 tcflush(int fd, int which)
diff --git a/lib/libc/gen/usleep.c b/lib/libc/gen/usleep.c
index 7d6559b..7c35f6c 100644
--- a/lib/libc/gen/usleep.c
+++ b/lib/libc/gen/usleep.c
@@ -38,6 +38,8 @@ __FBSDID("$FreeBSD$");
 #include <unistd.h>
 #include "un-namespace.h"
 
+#include "libc_private.h"
+
 int
 __usleep(useconds_t useconds)
 {
@@ -45,7 +47,8 @@ __usleep(useconds_t useconds)
 
 	time_to_sleep.tv_nsec = (useconds % 1000000) * 1000;
 	time_to_sleep.tv_sec = useconds / 1000000;
-	return (_nanosleep(&time_to_sleep, NULL));
+	return (((int (*)(const struct timespec *, struct timespec *))
+	    __libc_interposing[INTERPOS_nanosleep])(&time_to_sleep, NULL));
 }
 
 __weak_reference(__usleep, usleep);
diff --git a/lib/libc/gen/wait.c b/lib/libc/gen/wait.c
index 2169b9d..46a3fdd 100644
--- a/lib/libc/gen/wait.c
+++ b/lib/libc/gen/wait.c
@@ -40,10 +40,14 @@ __FBSDID("$FreeBSD$");
 #include <sys/resource.h>
 #include "un-namespace.h"
 
+#include "libc_private.h"
+
 pid_t
 __wait(int *istat)
 {
-	return (_wait4(WAIT_ANY, istat, 0, (struct rusage *)0));
+
+	return (((pid_t (*)(pid_t, int *, int, struct rusage *))
+	    __libc_interposing[INTERPOS_wait4])(WAIT_ANY, istat, 0, NULL));
 }
 
 __weak_reference(__wait, wait);
diff --git a/lib/libc/gen/wait3.c b/lib/libc/gen/wait3.c
index 6098773..965effe 100644
--- a/lib/libc/gen/wait3.c
+++ b/lib/libc/gen/wait3.c
@@ -40,11 +40,14 @@ __FBSDID("$FreeBSD$");
 #include <sys/resource.h>
 #include "un-namespace.h"
 
+#include "libc_private.h"
+
 pid_t
-wait3(istat, options, rup)
-	int *istat;
-	int options;
-	struct rusage *rup;
+__wait3(int *istat, int options, struct rusage *rup)
 {
-	return (_wait4(WAIT_ANY, istat, options, rup));
+
+	return (((pid_t (*)(pid_t, int *, int, struct rusage *))
+	    __libc_interposing[INTERPOS_wait4])(WAIT_ANY, istat, options, rup));
 }
+
+__weak_reference(__wait3, wait3);
diff --git a/lib/libc/gen/waitpid.c b/lib/libc/gen/waitpid.c
index b001837..5177591 100644
--- a/lib/libc/gen/waitpid.c
+++ b/lib/libc/gen/waitpid.c
@@ -40,10 +40,14 @@ __FBSDID("$FreeBSD$");
 #include <sys/resource.h>
 #include "un-namespace.h"
 
+#include "libc_private.h"
+
 pid_t
 __waitpid(pid_t pid, int *istat, int options)
 {
-	return (_wait4(pid, istat, options, (struct rusage *)0));
+
+	return (((pid_t (*)(pid_t, int *, int, struct rusage *))
+	    __libc_interposing[INTERPOS_wait4])(pid, istat, options, NULL));
 }
 
 __weak_reference(__waitpid, waitpid);