diff --git a/distrib/sets/lists/tests/mi b/distrib/sets/lists/tests/mi
index 5da6f5363eae..546a5db6de15 100644
--- a/distrib/sets/lists/tests/mi
+++ b/distrib/sets/lists/tests/mi
@@ -1,4 +1,4 @@
-# $NetBSD: mi,v 1.290 2011/04/04 16:32:41 jruoho Exp $
+# $NetBSD: mi,v 1.291 2011/04/04 19:08:42 jruoho Exp $
 #
 # Note: don't delete entries from here - mark them as "obsolete" instead.
 #
@@ -571,6 +571,7 @@
 ./usr/libdata/debug/usr/tests/syscall/t_getsid.debug			tests-syscall-debug	debug,atf
 ./usr/libdata/debug/usr/tests/syscall/t_mmap.debug			tests-syscall-debug	debug,atf
 ./usr/libdata/debug/usr/tests/syscall/t_mprotect.debug			tests-syscall-debug	debug,atf
+./usr/libdata/debug/usr/tests/syscall/t_setuid.debug			tests-syscall-debug	debug,atf
 ./usr/libdata/debug/usr/tests/syscall/t_timer.debug			tests-syscall-debug	debug,atf
 ./usr/libdata/debug/usr/tests/syscall/t_umask.debug			tests-syscall-debug	debug,atf
 ./usr/libdata/debug/usr/tests/usr.bin					tests-sbin-tests
@@ -2113,6 +2114,7 @@
 ./usr/tests/syscall/t_getsid			tests-syscall-tests	atf
 ./usr/tests/syscall/t_mmap			tests-syscall-tests	atf
 ./usr/tests/syscall/t_mprotect			tests-syscall-tests	atf
+./usr/tests/syscall/t_setuid			tests-syscall-tests	atf
 ./usr/tests/syscall/t_timer			tests-syscall-tests	atf
 ./usr/tests/syscall/t_umask			tests-syscall-tests	atf
 ./usr/tests/toolchain	tests-syscall-tests	atf
diff --git a/tests/syscall/Makefile b/tests/syscall/Makefile
index 27f86853ab77..e6b60ffc41ea 100644
--- a/tests/syscall/Makefile
+++ b/tests/syscall/Makefile
@@ -1,11 +1,11 @@
-# $NetBSD: Makefile,v 1.17 2011/04/04 16:32:41 jruoho Exp $
+# $NetBSD: Makefile,v 1.18 2011/04/04 19:08:43 jruoho Exp $
 
 .include <bsd.own.mk>
 
 TESTSDIR=	${TESTSBASE}/syscall
 
 TESTS_C+=	t_access t_cmsg t_dup t_fsync t_getpid t_getsid
-TESTS_C+=	t_mmap t_mprotect t_timer t_umask
+TESTS_C+=	t_mmap t_mprotect t_setuid t_timer t_umask
 
 LDADD.t_getpid+=-lpthread
 LDADD.t_timer+=	-lpthread
diff --git a/tests/syscall/t_setuid.c b/tests/syscall/t_setuid.c
new file mode 100644
index 000000000000..cefa33ef4074
--- /dev/null
+++ b/tests/syscall/t_setuid.c
@@ -0,0 +1,122 @@
+/* $NetBSD: t_setuid.c,v 1.1 2011/04/04 19:08:43 jruoho Exp $ */
+
+/*-
+ * Copyright (c) 2011 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to The NetBSD Foundation
+ * by Jukka Ruohonen.
+ *
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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>
+__RCSID("$NetBSD: t_setuid.c,v 1.1 2011/04/04 19:08:43 jruoho Exp $");
+
+#include <sys/wait.h>
+
+#include <atf-c.h>
+#include <errno.h>
+#include <pwd.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+ATF_TC(setuid_perm);
+ATF_TC_HEAD(setuid_perm, tc)
+{
+	atf_tc_set_md_var(tc, "descr", "Test setuid(0) as normal user");
+	atf_tc_set_md_var(tc, "require.user", "unprivileged");
+}
+
+ATF_TC_BODY(setuid_perm, tc)
+{
+	errno = 0;
+
+	ATF_REQUIRE(setuid(0) == -1);
+	ATF_REQUIRE(errno == EPERM);
+}
+
+ATF_TC(setuid_real);
+ATF_TC_HEAD(setuid_real, tc)
+{
+	atf_tc_set_md_var(tc, "descr", "Test setuid(2) with real UID");
+}
+
+ATF_TC_BODY(setuid_real, tc)
+{
+	uid_t uid = getuid();
+
+	ATF_REQUIRE(setuid(uid) == 0);
+
+	ATF_REQUIRE(getuid() == uid);
+	ATF_REQUIRE(geteuid() == uid);
+}
+
+ATF_TC(setuid_root);
+ATF_TC_HEAD(setuid_root, tc)
+{
+	atf_tc_set_md_var(tc, "descr", "A basic test of setuid(2)");
+	atf_tc_set_md_var(tc, "require.user", "root");
+}
+
+ATF_TC_BODY(setuid_root, tc)
+{
+	struct passwd *pw;
+	int rv, sta;
+	pid_t pid;
+	uid_t uid;
+
+	while ((pw = getpwent()) != NULL) {
+
+		pid = fork();
+		ATF_REQUIRE(pid >= 0);
+
+		if (pid == 0) {
+
+			rv = setuid(pw->pw_uid);
+
+			if (rv != 0)
+				_exit(EXIT_FAILURE);
+
+			uid = getuid();
+
+			if (uid != pw->pw_uid)
+				_exit(EXIT_FAILURE);
+
+			_exit(EXIT_SUCCESS);
+		}
+
+		(void)wait(&sta);
+
+		if (WIFEXITED(sta) == 0 || WEXITSTATUS(sta) != EXIT_SUCCESS)
+			atf_tc_fail("failed to change UID to %u", pw->pw_uid);
+	}
+}
+
+ATF_TP_ADD_TCS(tp)
+{
+
+	ATF_TP_ADD_TC(tp, setuid_perm);
+	ATF_TP_ADD_TC(tp, setuid_real);
+	ATF_TP_ADD_TC(tp, setuid_root);
+
+	return atf_no_error();
+}