Test that poll(2) returns POLLNVAL for an already closed fd.

poll(2) rewrite on top of kqueue is currently blocking instead of
returning.  Regression reported by Larry Hynes with a reproducer
from Leah Neukirchen, thanks a lot!

2 files changed, 42 insertions, 0 deletions

diff --git a/regress/sys/kern/poll/Makefile b/regress/sys/kern/poll/Makefile
new file mode 100644
index 00000000000..5b9265b9586
--- /dev/null
+++ b/regress/sys/kern/poll/Makefile
@@ -0,0 +1,5 @@
+#	$OpenBSD: Makefile,v 1.1 2021/10/29 13:13:04 mpi Exp $
+
+PROG=	pollnval
+
+.include <bsd.regress.mk>
diff --git a/regress/sys/kern/poll/pollnval.c b/regress/sys/kern/poll/pollnval.c
new file mode 100644
index 00000000000..adc9132e473
--- /dev/null
+++ b/regress/sys/kern/poll/pollnval.c
@@ -0,0 +1,37 @@
+/*	$OpenBSD: pollnval.c,v 1.1 2021/10/29 13:13:04 mpi Exp $	*/
+
+/*
+ * Copyright (c) 2021 Leah Neukirchen <leah@vuxu.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <assert.h>
+#include <stdio.h>
+#include <poll.h>
+#include <unistd.h>
+
+int
+main(void)
+{
+	struct pollfd fds[1];
+
+	fds[0].fd = 0;
+	fds[0].events = POLLIN | POLLHUP;
+	close(0);
+
+	assert(poll(fds, 1, -1) == 1);
+	assert(fds[0].revents & POLLNVAL);
+
+	return 0;
+}