From: bluhm <bluhm@openbsd.org>
Date: Mon, 10 Sep 2018 10:36:01 +0000 (+0000)
Subject: During the fork+exec implementation, daemon(3) was moved after
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=a9955862d6f72f7052d014379ab8b79e9489dbd5;p=openbsd

During the fork+exec implementation, daemon(3) was moved after
proc_init().  As a consequence vmd(8) child processes did not detach
from the terminal anymore.  Dup /dev/null to the stdio file descriptors
in the children.
OK mlarkin@ reyk@
---

diff --git a/usr.sbin/vmd/proc.c b/usr.sbin/vmd/proc.c
index b37036908cd..fde98994bc1 100644
--- a/usr.sbin/vmd/proc.c
+++ b/usr.sbin/vmd/proc.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: proc.c,v 1.17 2018/08/05 08:20:54 mestre Exp $	*/
+/*	$OpenBSD: proc.c,v 1.18 2018/09/10 10:36:01 bluhm Exp $	*/
 
 /*
  * Copyright (c) 2010 - 2016 Reyk Floeter <reyk@openbsd.org>
@@ -29,13 +29,14 @@
 #include <string.h>
 #include <errno.h>
 #include <signal.h>
+#include <paths.h>
 #include <pwd.h>
 #include <event.h>
 #include <imsg.h>
 
 #include "proc.h"
 
-void	 proc_exec(struct privsep *, struct privsep_proc *, unsigned int,
+void	 proc_exec(struct privsep *, struct privsep_proc *, unsigned int, int,
 	    int, char **);
 void	 proc_setup(struct privsep *, struct privsep_proc *, unsigned int);
 void	 proc_open(struct privsep *, int, int);
@@ -80,7 +81,7 @@ proc_getid(struct privsep_proc *procs, unsigned int nproc,
 
 void
 proc_exec(struct privsep *ps, struct privsep_proc *procs, unsigned int nproc,
-    int argc, char **argv)
+    int debug, int argc, char **argv)
 {
 	unsigned int		 proc, nargc, i, proc_i;
 	char			**nargv;
@@ -141,6 +142,16 @@ proc_exec(struct privsep *ps, struct privsep_proc *procs, unsigned int nproc,
 				} else if (fcntl(fd, F_SETFD, 0) == -1)
 					fatal("fcntl");
 
+				/* Daemons detach from terminal. */
+				if (!debug && (fd =
+				    open(_PATH_DEVNULL, O_RDWR, 0)) != -1) {
+					(void)dup2(fd, STDIN_FILENO);
+					(void)dup2(fd, STDOUT_FILENO);
+					(void)dup2(fd, STDERR_FILENO);
+					if (fd > 2)
+						(void)close(fd);
+				}
+
 				execvp(argv[0], nargv);
 				fatal("%s: execvp", __func__);
 				break;
@@ -191,7 +202,7 @@ proc_connect(struct privsep *ps)
 
 void
 proc_init(struct privsep *ps, struct privsep_proc *procs, unsigned int nproc,
-    int argc, char **argv, enum privsep_procid proc_id)
+    int debug, int argc, char **argv, enum privsep_procid proc_id)
 {
 	struct privsep_proc	*p = NULL;
 	struct privsep_pipes	*pa, *pb;
@@ -231,7 +242,7 @@ proc_init(struct privsep *ps, struct privsep_proc *procs, unsigned int nproc,
 		}
 
 		/* Engage! */
-		proc_exec(ps, procs, nproc, argc, argv);
+		proc_exec(ps, procs, nproc, debug, argc, argv);
 		return;
 	}
 
diff --git a/usr.sbin/vmd/proc.h b/usr.sbin/vmd/proc.h
index 01361076f54..5dfccb9cf09 100644
--- a/usr.sbin/vmd/proc.h
+++ b/usr.sbin/vmd/proc.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: proc.h,v 1.15 2018/08/05 08:20:54 mestre Exp $	*/
+/*	$OpenBSD: proc.h,v 1.16 2018/09/10 10:36:01 bluhm Exp $	*/
 
 /*
  * Copyright (c) 2010-2015 Reyk Floeter <reyk@openbsd.org>
@@ -156,7 +156,7 @@ struct privsep_fd {
 #define PROC_MAX_INSTANCES	32
 
 /* proc.c */
-void	 proc_init(struct privsep *, struct privsep_proc *, unsigned int,
+void	 proc_init(struct privsep *, struct privsep_proc *, unsigned int, int,
 	    int, char **, enum privsep_procid);
 void	 proc_kill(struct privsep *);
 void	 proc_connect(struct privsep *ps);
diff --git a/usr.sbin/vmd/vmd.c b/usr.sbin/vmd/vmd.c
index 2b07a8463b7..ac4d1635bd4 100644
--- a/usr.sbin/vmd/vmd.c
+++ b/usr.sbin/vmd/vmd.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: vmd.c,v 1.98 2018/07/15 14:36:54 reyk Exp $	*/
+/*	$OpenBSD: vmd.c,v 1.99 2018/09/10 10:36:01 bluhm Exp $	*/
 
 /*
  * Copyright (c) 2015 Reyk Floeter <reyk@openbsd.org>
@@ -792,7 +792,8 @@ main(int argc, char **argv)
 		ps->ps_title[proc_id] = title;
 
 	/* only the parent returns */
-	proc_init(ps, procs, nitems(procs), argc0, argv, proc_id);
+	proc_init(ps, procs, nitems(procs), env->vmd_debug, argc0, argv,
+	    proc_id);
 
 	log_procinit("parent");
 	if (!env->vmd_debug && daemon(0, 0) == -1)