1 files changed, 111 insertions, 0 deletions
diff --git a/usr/src/test/bhyve-tests/tests/vmm/datarw_constraints.c b/usr/src/test/bhyve-tests/tests/vmm/datarw_constraints.c
new file mode 100644
index 0000000000..82b13e2847
--- /dev/null
+++ b/usr/src/test/bhyve-tests/tests/vmm/datarw_constraints.c
@@ -0,0 +1,111 @@
+/*
+ * 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 2022 Oxide Computer Company
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <fcntl.h>
+#include <libgen.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <err.h>
+#include <assert.h>
+#include <sys/sysmacros.h>
+#include <stdbool.h>
+
+#include <sys/vmm.h>
+#include <sys/vmm_dev.h>
+#include <sys/vmm_data.h>
+#include <vmmapi.h>
+
+#include "common.h"
+
+static void
+should_eq_u32(const char *field_name, uint32_t a, uint32_t b)
+{
+	if (a != b) {
+		errx(EXIT_FAILURE, "unexpected %s %u != %u",
+		    field_name, a, b);
+	}
+}
+
+int
+main(int argc, char *argv[])
+{
+	const char *suite_name = basename(argv[0]);
+	struct vmctx *ctx;
+
+	ctx = create_test_vm(suite_name);
+	if (ctx == NULL) {
+		errx(EXIT_FAILURE, "could not open test VM");
+	}
+
+	/*
+	 * Check that vmm_data import/export facility is robust in the face of
+	 * potentially invalid inputs
+	 */
+	const int vmfd = vm_get_device_fd(ctx);
+
+	uint8_t buf[sizeof (struct vdi_atpic_v1) + sizeof (int)];
+	struct vm_data_xfer vdx = {
+		.vdx_class = VDC_ATPIC,
+		.vdx_version = 1,
+		.vdx_len = sizeof (struct vdi_atpic_v1),
+		.vdx_data = buf,
+	};
+
+	/* Attempt a valid-sized read first */
+	if (ioctl(vmfd, VM_DATA_READ, &vdx) != 0) {
+		err(EXIT_FAILURE, "valid vmm_dat_read failed");
+	}
+	should_eq_u32("vdx_result_len", vdx.vdx_result_len,
+	    sizeof (struct vdi_atpic_v1));
+
+	/* ... then too-small ... */
+	vdx.vdx_len = sizeof (struct vdi_atpic_v1) - sizeof (int);
+	vdx.vdx_result_len = 0;
+	if (ioctl(vmfd, VM_DATA_READ, &vdx) == 0) {
+		errx(EXIT_FAILURE, "invalid vmm_dat_read should have failed");
+	}
+	int error = errno;
+	if (error != ENOSPC) {
+		errx(EXIT_FAILURE, "expected ENOSPC errno, got %d", error);
+	}
+	/* the "correct" vdx_result_len should still be communicated out */
+	should_eq_u32("vdx_result_len", vdx.vdx_result_len,
+	    sizeof (struct vdi_atpic_v1));
+
+	/*
+	 * ... and too-big to round it out.
+	 *
+	 * This should pass, but still set vdx_result_len to the actual length
+	 */
+	vdx.vdx_len = sizeof (struct vdi_atpic_v1) + sizeof (int);
+	vdx.vdx_result_len = 0;
+	if (ioctl(vmfd, VM_DATA_READ, &vdx) != 0) {
+		err(EXIT_FAILURE, "too-large (but valid) vmm_dat_read failed");
+	}
+	should_eq_u32("vdx_result_len", vdx.vdx_result_len,
+	    sizeof (struct vdi_atpic_v1));
+
+	/*
+	 * The vmm_data_write paths should also be tested, but not until they
+	 * are exposed to the general public without requring mdb -kw settings.
+	 */
+
+	vm_destroy(ctx);
+	(void) printf("%s\tPASS\n", suite_name);
+	return (EXIT_SUCCESS);
+}