Try to confuse /dev/fd (might crash the kernel on other systems or if someone screws up in the kernel).

2 files changed, 46 insertions, 0 deletions

diff --git a/regress/sys/fdescfs/confuse/Makefile b/regress/sys/fdescfs/confuse/Makefile
new file mode 100644
index 00000000000..40401cd70c7
--- /dev/null
+++ b/regress/sys/fdescfs/confuse/Makefile
@@ -0,0 +1,5 @@
+#	$OpenBSD: Makefile,v 1.1 2002/02/08 17:33:32 art Exp $
+
+PROG=	confuse
+
+.include <bsd.regress.mk>
diff --git a/regress/sys/fdescfs/confuse/confuse.c b/regress/sys/fdescfs/confuse/confuse.c
new file mode 100644
index 00000000000..4fb68d94e32
--- /dev/null
+++ b/regress/sys/fdescfs/confuse/confuse.c
@@ -0,0 +1,41 @@
+/*	$OpenBSD: confuse.c,v 1.1 2002/02/08 17:33:32 art Exp $	*/
+/*
+ *	Written by Artur Grabowski <art@openbsd.org> 2002 Public Domain.
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <err.h>
+#include <fcntl.h>
+#include <errno.h>
+
+int
+main()
+{
+	char fname[64];
+	int fd, newfd;
+
+	if ((fd = open("/dev/null", O_RDONLY)) < 0)
+		err(1, "open(/dev/null)");
+
+	/* Try to confuse fdescfs by making it open into itself. */
+	close(fd);
+
+	snprintf(fname, sizeof(fname), "/dev/fd/%d", fd);
+
+	if ((newfd = open(fname, O_RDONLY)) == fd)
+		errx(1, "open of %s to %d succeeded, beware.", fname, fd);
+
+	if (newfd >= 0)
+		errx(1, "open(%s) gave us the unexpected %d", fname, fd);
+
+	if (errno == ENOENT)
+		err(1, "open(%s)", fname);
+
+	if (errno == ENXIO)
+		errx(1, "no support for fdesc in kernel"); 
+
+	warn("errno was (%d)", errno);
+
+	return 0;
+}