14005 eventfd_read/write() don't return failure

Reviewed by: Robert Mustacchi <rm@fingolfin.org>
Reviewed by: Dan McDonald <danmcd@joyent.com>
Approved by: Robert Mustacchi <rm@fingolfin.org>

5 files changed, 158 insertions, 4 deletions

diff --git a/usr/src/lib/libc/port/sys/eventfd.c b/usr/src/lib/libc/port/sys/eventfd.c
index f165491cc1..d0d42e8f74 100644
--- a/usr/src/lib/libc/port/sys/eventfd.c
+++ b/usr/src/lib/libc/port/sys/eventfd.c
@@ -11,6 +11,7 @@
 
 /*
  * Copyright (c) 2015, Joyent, Inc.  All rights reserved.
+ * Copyright 2021 OmniOS Community Edition (OmniOSce) Association.
  */
 
 #include <sys/eventfd.h>
@@ -57,11 +58,17 @@ eventfd(unsigned int initval, int flags)
 int
 eventfd_read(int fd, eventfd_t *valp)
 {
-	return (read(fd, valp, sizeof (*valp)) < sizeof (*valp) ? -1 : 0);
+	ssize_t ret = read(fd, valp, sizeof (*valp));
+	if (ret == -1 || (size_t)ret < sizeof (*valp))
+		return (-1);
+	return (0);
 }
 
 int
 eventfd_write(int fd, eventfd_t val)
 {
-	return (write(fd, &val, sizeof (val)) < sizeof (val) ? -1 : 0);
+	ssize_t ret = write(fd, &val, sizeof (val));
+	if (ret == -1 || (size_t)ret < sizeof (val))
+		return (-1);
+	return (0);
 }
diff --git a/usr/src/pkg/manifests/system-test-ostest.mf b/usr/src/pkg/manifests/system-test-ostest.mf
index 596c19fb5d..e929737c68 100644
--- a/usr/src/pkg/manifests/system-test-ostest.mf
+++ b/usr/src/pkg/manifests/system-test-ostest.mf
@@ -13,7 +13,7 @@
 # Copyright (c) 2012, 2016 by Delphix. All rights reserved.
 # Copyright 2014, OmniTI Computer Consulting, Inc. All rights reserved.
 # Copyright 2020 Joyent, Inc.
-# Copyright 2020 OmniOS Community Edition (OmniOSce) Association.
+# Copyright 2021 OmniOS Community Edition (OmniOSce) Association.
 # Copyright 2021 Tintri by DDN, Inc. All rights reserved.
 #
 
@@ -53,6 +53,8 @@ file path=opt/os-tests/tests/ddi_ufm/ufm-test mode=0555
 file path=opt/os-tests/tests/ddi_ufm/ufm-test-cleanup mode=0555
 file path=opt/os-tests/tests/ddi_ufm/ufm-test-setup mode=0555
 file path=opt/os-tests/tests/epoll_test mode=0555
+file path=opt/os-tests/tests/eventfd.32 mode=0555
+file path=opt/os-tests/tests/eventfd.64 mode=0555
 file path=opt/os-tests/tests/file-locking/acquire-lock.32 mode=0555
 file path=opt/os-tests/tests/file-locking/acquire-lock.64 mode=0555
 file path=opt/os-tests/tests/file-locking/runtests.32 mode=0555
diff --git a/usr/src/test/os-tests/runfiles/default.run b/usr/src/test/os-tests/runfiles/default.run
index e7b44684db..ecc3134fe5 100644
--- a/usr/src/test/os-tests/runfiles/default.run
+++ b/usr/src/test/os-tests/runfiles/default.run
@@ -12,7 +12,7 @@
 #
 # Copyright (c) 2012 by Delphix. All rights reserved.
 # Copyright 2020 Joyent, Inc.
-# Copyright 2020 OmniOS Community Edition (OmniOSce) Association.
+# Copyright 2021 OmniOS Community Edition (OmniOSce) Association.
 # Copyright 2021 Tintri by DDN, Inc. All rights reserved.
 #
 
@@ -28,6 +28,9 @@ outputdir = /var/tmp/test_results
 user = root
 tests = ['poll_test', 'epoll_test']
 
+[/opt/os-tests/tests/eventfd.32]
+[/opt/os-tests/tests/eventfd.64]
+
 [/opt/os-tests/tests/odirectory.32]
 [/opt/os-tests/tests/odirectory.64]
 
diff --git a/usr/src/test/os-tests/tests/Makefile b/usr/src/test/os-tests/tests/Makefile
index 2783408243..c2c8b9046d 100644
--- a/usr/src/test/os-tests/tests/Makefile
+++ b/usr/src/test/os-tests/tests/Makefile
@@ -13,6 +13,7 @@
 # Copyright (c) 2012, 2016 by Delphix. All rights reserved.
 # Copyright 2020 Joyent, Inc.
 # Copyright 2021 Tintri by DDN, Inc. All rights reserved.
+# Copyright 2021 OmniOS Community Edition (OmniOSce) Association.
 #
 
 SUBDIRS_i386 = i386 imc
@@ -37,6 +38,7 @@ SUBDIRS =       \
 		$(SUBDIRS_$(MACH))
 
 PROGS = \
+	eventfd \
 	odirectory \
 	writev
 
diff --git a/usr/src/test/os-tests/tests/eventfd.c b/usr/src/test/os-tests/tests/eventfd.c
new file mode 100644
index 0000000000..bb6ab7dc7d
--- /dev/null
+++ b/usr/src/test/os-tests/tests/eventfd.c
@@ -0,0 +1,140 @@
+/*
+ * This file and its contents are supplied under the terms of the
+ * Common Development and Distribution License ("CDDL"), version 1.0.
+ * You may only use this file in accordance with the terms of version
+ * 1.0 of the CDDL.
+ *
+ * A full copy of the text of the CDDL should have accompanied this
+ * source.  A copy of the CDDL is also available via the Internet at
+ * http://www.illumos.org/license/CDDL.
+ */
+
+/*
+ * Copyright 2021 OmniOS Community Edition (OmniOSce) Association.
+ */
+
+#include <err.h>
+#include <errno.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/debug.h>
+#include <sys/eventfd.h>
+#include <unistd.h>
+
+static int
+readn(int fd, uint_t n)
+{
+	uint_t i;
+	int failures = 0;
+
+	for (i = 0; i < n; i++) {
+		eventfd_t v = 0xdeadbeef;
+		int ret;
+
+		ret = eventfd_read(fd, &v);
+		if (ret != 0) {
+			warn("Reading %u/%u got ret %d (expected 0)",
+			    i + 1, n, ret);
+			failures++;
+		} else if (v != 1) {
+			warnx("Reading %u/%u got value %"PRIu64" (expected 1)",
+			    i + 1, n, v);
+			failures++;
+		}
+	}
+
+	return (failures);
+}
+
+static int
+check_nosem(int fd)
+{
+	eventfd_t v = 0xdeadbeef;
+	int failures = 0;
+	int ret;
+
+	ret = eventfd_read(fd, &v);
+
+	if (ret != -1) {
+		warnx("no semaphores read got ret %d (expected -1)", ret);
+		failures++;
+	}
+
+	if (errno != EAGAIN) {
+		warn("no semaphores read expected EAGAIN but got");
+		failures++;
+	}
+
+	if (v != 0xdeadbeef) {
+		warnx("no semaphores read modified value to %"PRIx64, v);
+		failures++;
+	}
+
+	return (failures);
+}
+
+static int
+check_badwrite(int fd)
+{
+	int failures = 0;
+	int ret;
+
+	ret = eventfd_write(fd, ULLONG_MAX);
+
+	if (ret != -1) {
+		warnx("bad write got ret %d (expected -1)", ret);
+		failures++;
+	}
+
+	if (errno != EINVAL) {
+		warn("bad write expected EINVAL but got");
+		failures++;
+	}
+
+	return (failures);
+}
+
+int
+main(void)
+{
+	int fd, failures = 0;
+
+	/* Test eventfd semaphore semantics */
+	fd = eventfd(2, EFD_NONBLOCK | EFD_CLOEXEC | EFD_SEMAPHORE);
+	if (fd == -1)
+		err(EXIT_FAILURE, "Could not create eventfd semaphore");
+
+	/* Consume the available semaphores */
+	failures += readn(fd, 2);
+
+	/* The next read should return -1/EAGAIN */
+	failures += check_nosem(fd);
+
+	/* Return two + three semaphores */
+	if (eventfd_write(fd, 2) != 0) {
+		warn("Error while returning two semaphores");
+		failures++;
+	}
+	if (eventfd_write(fd, 3) != 0) {
+		warn("Error while returning three semaphores");
+		failures++;
+	}
+
+	/* Consume the available semaphores */
+	failures += readn(fd, 5);
+
+	/* The next read should return -1/EAGAIN */
+	failures += check_nosem(fd);
+
+	/*
+	 * Check that a writing too large a value results in an error from
+	 * eventfd_write() - testing that an error from the underlying write()
+	 * is passed back.
+	 */
+	failures += check_badwrite(fd);
+
+	VERIFY0(close(fd));
+
+	return (failures == 0 ? EXIT_SUCCESS : EXIT_FAILURE);
+}