From ef1ca8b6f4fcfbe233bcdc3aa205782d3f1e7513 Mon Sep 17 00:00:00 2001
From: deraadt <deraadt@openbsd.org>
Date: Fri, 9 Oct 2015 23:55:03 +0000
Subject: [PATCH] Allow kill(self, sig) in pledge SELF also.  the stack
 protector, abort(), and readpassphrase() in particular use this. ok millert
 tedu semarie

---
 sys/kern/kern_pledge.c |  4 ++--
 sys/kern/kern_sig.c    | 11 ++++++++++-
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/sys/kern/kern_pledge.c b/sys/kern/kern_pledge.c
index ed5fbf7eccc..ef2314ace41 100644
--- a/sys/kern/kern_pledge.c
+++ b/sys/kern/kern_pledge.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_pledge.c,v 1.5 2015/10/09 17:18:20 deraadt Exp $	*/
+/*	$OpenBSD: kern_pledge.c,v 1.6 2015/10/09 23:55:03 deraadt Exp $	*/
 
 /*
  * Copyright (c) 2015 Nicholas Marriott <nicm@openbsd.org>
@@ -136,7 +136,7 @@ const u_int pledge_syscalls[SYS_MAXSYSCALL] = {
 
 	[SYS_fork] = PLEDGE_PROC,
 	[SYS_vfork] = PLEDGE_PROC,
-	[SYS_kill] = PLEDGE_PROC,
+	[SYS_kill] = PLEDGE_SELF | PLEDGE_PROC,	
 	[SYS_setpgid] = PLEDGE_PROC,
 	[SYS_sigsuspend] = PLEDGE_PROC,
 	[SYS_setrlimit] = PLEDGE_PROC,
diff --git a/sys/kern/kern_sig.c b/sys/kern/kern_sig.c
index 87a85a1958d..e4a17024f77 100644
--- a/sys/kern/kern_sig.c
+++ b/sys/kern/kern_sig.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_sig.c,v 1.184 2015/10/09 01:10:27 deraadt Exp $	*/
+/*	$OpenBSD: kern_sig.c,v 1.185 2015/10/09 23:55:03 deraadt Exp $	*/
 /*	$NetBSD: kern_sig.c,v 1.54 1996/04/22 01:38:32 christos Exp $	*/
 
 /*
@@ -62,6 +62,7 @@
 #include <sys/sched.h>
 #include <sys/user.h>
 #include <sys/syslog.h>
+#include <sys/pledge.h>
 
 #include <sys/mount.h>
 #include <sys/syscallargs.h>
@@ -569,6 +570,14 @@ sys_kill(struct proc *cp, void *v, register_t *retval)
 	int pid = SCARG(uap, pid);
 	int signum = SCARG(uap, signum);
 
+	if (cp->p_p->ps_flags & PS_PLEDGE) {
+		/* PLEDGE_PROC is required to signal another pid */
+		if ((cp->p_p->ps_pledge & PLEDGE_PROC) || pid == cp->p_pid)
+			;
+		else
+			return pledge_fail(cp, EPERM, PLEDGE_SELF);
+	}
+
 	if (((u_int)signum) >= NSIG)
 		return (EINVAL);
 	if (pid > 0) {
-- 
2.20.1