Split the intra-thread functionality from kill(2) into its own syscall

thrkill(2), rolling the kill(2) syscall number with the ABI change to
avoid breaking binaries during during the transition.  thrkill(2) includes
a 'tcb' argument that eliminates the need for locking in pthread_kill()
and simplifies pthread_cancel().  Switch __stack_smash_handler() to use
thrkill(2) and explicitly unblock SIGABRT.

Minor bump to both libc and libpthread: make sure you install a new kernel!

ok semarie@

7 files changed, 119 insertions, 12 deletions

diff --git a/lib/libc/Symbols.list b/lib/libc/Symbols.list
index 2c9c55189ca..70770229cd1 100644
--- a/lib/libc/Symbols.list
+++ b/lib/libc/Symbols.list
@@ -228,6 +228,7 @@ _thread_sys_symlinkat
 _thread_sys_sync
 _thread_sys_sysarch
 _thread_sys_sysctl
+_thread_sys_thrkill
 _thread_sys_truncate
 _thread_sys_umask
 _thread_sys_unlink
@@ -430,6 +431,7 @@ timer_delete
 timer_getoverrun
 timer_gettime
 timer_settime
+thrkill
 truncate
 umask
 unlink
diff --git a/lib/libc/gen/raise.c b/lib/libc/gen/raise.c
index b477183d141..a0fa5b0f1b0 100644
--- a/lib/libc/gen/raise.c
+++ b/lib/libc/gen/raise.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: raise.c,v 1.7 2015/09/12 16:46:12 guenther Exp $ */
+/*	$OpenBSD: raise.c,v 1.8 2015/11/10 04:30:59 guenther Exp $ */
 /*-
  * Copyright (c) 1990, 1993
  *	The Regents of the University of California.  All rights reserved.
@@ -34,6 +34,6 @@
 int
 raise(int s)
 {
-	return (kill(getthrid(), s));
+	return (thrkill(0, s, NULL));
 }
 DEF_STRONG(raise);
diff --git a/lib/libc/hidden/signal.h b/lib/libc/hidden/signal.h
index f23578d725d..5a1f17fb5c1 100644
--- a/lib/libc/hidden/signal.h
+++ b/lib/libc/hidden/signal.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: signal.h,v 1.9 2015/10/25 04:13:59 guenther Exp $	*/
+/*	$OpenBSD: signal.h,v 1.10 2015/11/10 04:30:59 guenther Exp $	*/
 /*
  * Copyright (c) 2015 Philip Guenther <guenther@openbsd.org>
  *
@@ -52,5 +52,6 @@ PROTO_NORMAL(sigreturn);
 PROTO_NORMAL(sigsetmask);
 /*PROTO_CANCEL(sigsuspend);	wrap to hide SIGTHR */
 PROTO_DEPRECATED(sigvec);
+PROTO_NORMAL(thrkill);
 
 #endif	/* !_LIBC_SIGNAL_H */
diff --git a/lib/libc/shlib_version b/lib/libc/shlib_version
index 4635d2ba64c..fce886b2e0a 100644
--- a/lib/libc/shlib_version
+++ b/lib/libc/shlib_version
@@ -1,4 +1,4 @@
 major=84
-minor=0
+minor=1
 # note: If changes were made to include/thread_private.h or if system
 # calls were added/changed then librthread/shlib_version also be updated.
diff --git a/lib/libc/sys/Makefile.inc b/lib/libc/sys/Makefile.inc
index 9fa5eb947d2..a6cd01ed765 100644
--- a/lib/libc/sys/Makefile.inc
+++ b/lib/libc/sys/Makefile.inc
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile.inc,v 1.135 2015/10/23 04:39:24 guenther Exp $
+#	$OpenBSD: Makefile.inc,v 1.136 2015/11/10 04:30:59 guenther Exp $
 #	$NetBSD: Makefile.inc,v 1.35 1995/10/16 23:49:07 jtc Exp $
 #	@(#)Makefile.inc	8.1 (Berkeley) 6/17/93
 
@@ -57,7 +57,7 @@ ASM=	__get_tcb.o __getcwd.o __semctl.o __set_tcb.o __syscall.o \
 	settimeofday.o setuid.o shmat.o shmctl.o shmdt.o \
 	shmget.o shutdown.o sigaltstack.o socket.o \
 	socketpair.o stat.o statfs.o swapctl.o symlink.o symlinkat.o \
-	sync.o sysarch.o sysctl.o umask.o unlink.o unlinkat.o \
+	sync.o sysarch.o sysctl.o thrkill.o umask.o unlink.o unlinkat.o \
 	unmount.o utimensat.o utimes.o utrace.o wait4.o write.o writev.o
 
 SRCS+=	${SRCS_${MACHINE_CPU}}
@@ -166,7 +166,7 @@ MAN+=	__get_tcb.2 __thrsigdivert.2 __thrsleep.2 _exit.2 accept.2 \
 	shmctl.2 shmget.2 shutdown.2 sigaction.2 sigaltstack.2 sigpending.2 \
 	sigprocmask.2 sigreturn.2 sigsuspend.2 socket.2 \
 	socketpair.2 stat.2 statfs.2 swapctl.2 symlink.2 \
-	sync.2 sysarch.2 syscall.2 truncate.2 umask.2 unlink.2 \
+	sync.2 sysarch.2 syscall.2 thrkill.2 truncate.2 umask.2 unlink.2 \
 	utimes.2 utrace.2 vfork.2 wait.2 write.2
 
 MLINKS+=__get_tcb.2 __set_tcb.2
diff --git a/lib/libc/sys/stack_protector.c b/lib/libc/sys/stack_protector.c
index 75c7ef83d79..e61a5f2f82f 100644
--- a/lib/libc/sys/stack_protector.c
+++ b/lib/libc/sys/stack_protector.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: stack_protector.c,v 1.18 2015/11/10 04:14:03 guenther Exp $	*/
+/*	$OpenBSD: stack_protector.c,v 1.19 2015/11/10 04:30:59 guenther Exp $	*/
 
 /*
  * Copyright (c) 2002 Hiroaki Etoh, Federico G. Schwindt, and Miodrag Vallat.
@@ -57,18 +57,17 @@ __stack_smash_handler(const char func[], int damaged)
 	/* Immediately block all signal handlers from running code */
 	sigfillset(&mask);
 	sigdelset(&mask, SIGABRT);
-	sigprocmask(SIG_BLOCK, &mask, NULL);
+	sigprocmask(SIG_SETMASK, &mask, NULL);
 
-	/* This may fail on a chroot jail... */
 	syslog_r(LOG_CRIT, &sdata, message, func);
 
-	bzero(&sa, sizeof(struct sigaction));
+	memset(&sa, 0, sizeof(sa));
 	sigemptyset(&sa.sa_mask);
 	sa.sa_flags = 0;
 	sa.sa_handler = SIG_DFL;
 	sigaction(SIGABRT, &sa, NULL);
 
-	kill(getpid(), SIGABRT);
+	thrkill(0, SIGABRT, NULL);
 
 	_exit(127);
 }
diff --git a/lib/libc/sys/thrkill.2 b/lib/libc/sys/thrkill.2
new file mode 100644
index 00000000000..88fe1edebe7
--- /dev/null
+++ b/lib/libc/sys/thrkill.2
@@ -0,0 +1,105 @@
+.\"	$OpenBSD: thrkill.2,v 1.1 2015/11/10 04:30:59 guenther Exp $
+.\"	$NetBSD: kill.2,v 1.7 1995/02/27 12:33:53 cgd Exp $
+.\"
+.\" Copyright (c) 1980, 1991, 1993
+.\"	The Regents of the University of California.  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. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. Neither the name of the University 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 REGENTS 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 REGENTS 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.
+.\"
+.\"     @(#)kill.2	8.3 (Berkeley) 4/19/94
+.\"
+.Dd $Mdocdate: November 10 2015 $
+.Dt THRKILL 2
+.Os
+.Sh NAME
+.Nm thrkill
+.Nd send signal to a thread in the same process
+.Sh SYNOPSIS
+.In signal.h
+.Ft int
+.Fn thrkill "pid_t tid" "int sig" "void *tcb"
+.Sh DESCRIPTION
+The
+.Fn thrkill
+function sends the signal given by
+.Fa sig
+to
+.Fa tid ,
+a thread in the same process as the caller.
+.Fn thrkill
+will only succeed if
+.Fa tcb
+is either
+.Dv NULL
+or the address of the thread control block (TCB) of the target thread.
+.Fa sig
+may be one of the signals specified in
+.Xr sigaction 2
+or it may be 0, in which case
+error checking is performed but no
+signal is actually sent.
+.Pp
+If
+.Fa tid
+is zero then the current thread is targeted.
+.Sh RETURN VALUES
+.Rv -std
+.Sh ERRORS
+.Fn thrkill
+will fail and no signal will be sent if:
+.Bl -tag -width Er
+.It Bq Er EINVAL
+.Fa sig
+is not a valid signal number.
+.It Bq Er ESRCH
+The process doesn't have a thread with thread ID
+.Fa tid .
+.It Bq Er ESRCH
+.Fa tcb
+is not
+.Dv NULL
+and not the TCB address of the thread with thread ID
+.Fa tid .
+.El
+.Sh SEE ALSO
+.Xr __get_tcb 2 ,
+.Xr kill 2 ,
+.Xr sigaction 2 ,
+.Xr pthread_kill 3 ,
+.Xr raise 3
+.Sh STANDARDS
+The
+.Fn __thrsigdivert
+function is specific to
+.Ox
+and should not be used in portable applications.
+Use
+.Xr pthread_kill 3
+instead.
+.Sh HISTORY
+The
+.Fn thrkill
+system call appeared in
+.Ox 5.9 .