Merge branch 'mctp-kunit-tests'

Jeremy Kerr says:

====================
MCTP kunit tests

This change adds some initial kunit tests for the MCTP core. We'll
expand the coverage in a future series, and augment with a few
selftests, but this establishes a baseline set of tests for now.

Thanks to the kunit folks for the framework!

---

v2:
 - fix MCTP=m, KUNIT={y,m} breakage
 - fix mctp test netdev initialisation
 - strict route reference count checking
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

net/mctp/Kconfig

@@ -11,3 +11,8 @@ menuconfig MCTP
 	  This option enables core MCTP support. For communicating with other
 	  devices, you'll want to enable a driver for a specific hardware
 	  channel.
+
+config MCTP_TEST
+        bool "MCTP core tests" if !KUNIT_ALL_TESTS
+        depends on MCTP=y && KUNIT=y
+        default KUNIT_ALL_TESTS

net/mctp/Makefile

 # SPDX-License-Identifier: GPL-2.0
 obj-$(CONFIG_MCTP) += mctp.o
 mctp-objs := af_mctp.o device.o route.o neigh.o
+
+# tests
+obj-$(CONFIG_MCTP_TEST) += test/utils.o

net/mctp/route.c

@@ -11,6 +11,7 @@
  */
 
 #include <linux/idr.h>
+#include <linux/kconfig.h>
 #include <linux/mctp.h>
 #include <linux/netdevice.h>
 #include <linux/rtnetlink.h>
@@ -1228,3 +1229,7 @@ void __exit mctp_routes_exit(void)
 	rtnl_unregister(PF_MCTP, RTM_GETROUTE);
 	dev_remove_pack(&mctp_packet_type);
 }
+
+#if IS_ENABLED(CONFIG_MCTP_TEST)
+#include "test/route-test.c"
+#endif

net/mctp/test/route-test.c

+// SPDX-License-Identifier: GPL-2.0
+
+#include <kunit/test.h>
+
+#include "utils.h"
+
+struct mctp_test_route {
+	struct mctp_route	rt;
+	struct sk_buff_head	pkts;
+};
+
+static int mctp_test_route_output(struct mctp_route *rt, struct sk_buff *skb)
+{
+	struct mctp_test_route *test_rt = container_of(rt, struct mctp_test_route, rt);
+
+	skb_queue_tail(&test_rt->pkts, skb);
+
+	return 0;
+}
+
+/* local version of mctp_route_alloc() */
+static struct mctp_test_route *mctp_route_test_alloc(void)
+{
+	struct mctp_test_route *rt;
+
+	rt = kzalloc(sizeof(*rt), GFP_KERNEL);
+	if (!rt)
+		return NULL;
+
+	INIT_LIST_HEAD(&rt->rt.list);
+	refcount_set(&rt->rt.refs, 1);
+	rt->rt.output = mctp_test_route_output;
+
+	skb_queue_head_init(&rt->pkts);
+
+	return rt;
+}
+
+static struct mctp_test_route *mctp_test_create_route(struct net *net,
+						      struct mctp_dev *dev,
+						      mctp_eid_t eid,
+						      unsigned int mtu)
+{
+	struct mctp_test_route *rt;
+
+	rt = mctp_route_test_alloc();
+	if (!rt)
+		return NULL;
+
+	rt->rt.min = eid;
+	rt->rt.max = eid;
+	rt->rt.mtu = mtu;
+	rt->rt.type = RTN_UNSPEC;
+	if (dev)
+		mctp_dev_hold(dev);
+	rt->rt.dev = dev;
+
+	list_add_rcu(&rt->rt.list, &net->mctp.routes);
+
+	return rt;
+}
+
+static void mctp_test_route_destroy(struct kunit *test,
+				    struct mctp_test_route *rt)
+{
+	unsigned int refs;
+
+	rtnl_lock();
+	list_del_rcu(&rt->rt.list);
+	rtnl_unlock();
+
+	skb_queue_purge(&rt->pkts);
+	if (rt->rt.dev)
+		mctp_dev_put(rt->rt.dev);
+
+	refs = refcount_read(&rt->rt.refs);
+	KUNIT_ASSERT_EQ_MSG(test, refs, 1, "route ref imbalance");
+
+	kfree_rcu(&rt->rt, rcu);
+}
+
+static struct sk_buff *mctp_test_create_skb(const struct mctp_hdr *hdr,
+					    unsigned int data_len)
+{
+	size_t hdr_len = sizeof(*hdr);
+	struct sk_buff *skb;
+	unsigned int i;
+	u8 *buf;
+
+	skb = alloc_skb(hdr_len + data_len, GFP_KERNEL);
+	if (!skb)
+		return NULL;
+
+	memcpy(skb_put(skb, hdr_len), hdr, hdr_len);
+
+	buf = skb_put(skb, data_len);
+	for (i = 0; i < data_len; i++)
+		buf[i] = i & 0xff;
+
+	return skb;
+}
+
+static struct sk_buff *__mctp_test_create_skb_data(const struct mctp_hdr *hdr,
+						   const void *data,
+						   size_t data_len)
+{
+	size_t hdr_len = sizeof(*hdr);
+	struct sk_buff *skb;
+
+	skb = alloc_skb(hdr_len + data_len, GFP_KERNEL);
+	if (!skb)
+		return NULL;
+
+	memcpy(skb_put(skb, hdr_len), hdr, hdr_len);
+	memcpy(skb_put(skb, data_len), data, data_len);
+
+	return skb;
+}
+
+#define mctp_test_create_skb_data(h, d) \
+	__mctp_test_create_skb_data(h, d, sizeof(*d))
+
+struct mctp_frag_test {
+	unsigned int mtu;
+	unsigned int msgsize;
+	unsigned int n_frags;
+};
+
+static void mctp_test_fragment(struct kunit *test)
+{
+	const struct mctp_frag_test *params;
+	int rc, i, n, mtu, msgsize;
+	struct mctp_test_route *rt;
+	struct sk_buff *skb;
+	struct mctp_hdr hdr;
+	u8 seq;
+
+	params = test->param_value;
+	mtu = params->mtu;
+	msgsize = params->msgsize;
+
+	hdr.ver = 1;
+	hdr.src = 8;
+	hdr.dest = 10;
+	hdr.flags_seq_tag = MCTP_HDR_FLAG_TO;
+
+	skb = mctp_test_create_skb(&hdr, msgsize);
+	KUNIT_ASSERT_TRUE(test, skb);
+
+	rt = mctp_test_create_route(&init_net, NULL, 10, mtu);
+	KUNIT_ASSERT_TRUE(test, rt);
+
+	/* The refcount would usually be incremented as part of a route lookup,
+	 * but we're setting the route directly here.
+	 */
+	refcount_inc(&rt->rt.refs);
+
+	rc = mctp_do_fragment_route(&rt->rt, skb, mtu, MCTP_TAG_OWNER);
+	KUNIT_EXPECT_FALSE(test, rc);
+
+	n = rt->pkts.qlen;
+
+	KUNIT_EXPECT_EQ(test, n, params->n_frags);
+
+	for (i = 0;; i++) {
+		struct mctp_hdr *hdr2;
+		struct sk_buff *skb2;
+		u8 tag_mask, seq2;
+		bool first, last;
+
+		first = i == 0;
+		last = i == (n - 1);
+
+		skb2 = skb_dequeue(&rt->pkts);
+
+		if (!skb2)
+			break;
+
+		hdr2 = mctp_hdr(skb2);
+
+		tag_mask = MCTP_HDR_TAG_MASK | MCTP_HDR_FLAG_TO;
+
+		KUNIT_EXPECT_EQ(test, hdr2->ver, hdr.ver);
+		KUNIT_EXPECT_EQ(test, hdr2->src, hdr.src);
+		KUNIT_EXPECT_EQ(test, hdr2->dest, hdr.dest);
+		KUNIT_EXPECT_EQ(test, hdr2->flags_seq_tag & tag_mask,
+				hdr.flags_seq_tag & tag_mask);
+
+		KUNIT_EXPECT_EQ(test,
+				!!(hdr2->flags_seq_tag & MCTP_HDR_FLAG_SOM), first);
+		KUNIT_EXPECT_EQ(test,
+				!!(hdr2->flags_seq_tag & MCTP_HDR_FLAG_EOM), last);
+
+		seq2 = (hdr2->flags_seq_tag >> MCTP_HDR_SEQ_SHIFT) &
+			MCTP_HDR_SEQ_MASK;
+
+		if (first) {
+			seq = seq2;
+		} else {
+			seq++;
+			KUNIT_EXPECT_EQ(test, seq2, seq & MCTP_HDR_SEQ_MASK);
+		}
+
+		if (!last)
+			KUNIT_EXPECT_EQ(test, skb2->len, mtu);
+		else
+			KUNIT_EXPECT_LE(test, skb2->len, mtu);
+
+		kfree_skb(skb2);
+	}
+
+	mctp_test_route_destroy(test, rt);
+}
+
+static const struct mctp_frag_test mctp_frag_tests[] = {
+	{.mtu = 68, .msgsize = 63, .n_frags = 1},
+	{.mtu = 68, .msgsize = 64, .n_frags = 1},
+	{.mtu = 68, .msgsize = 65, .n_frags = 2},
+	{.mtu = 68, .msgsize = 66, .n_frags = 2},
+	{.mtu = 68, .msgsize = 127, .n_frags = 2},
+	{.mtu = 68, .msgsize = 128, .n_frags = 2},
+	{.mtu = 68, .msgsize = 129, .n_frags = 3},
+	{.mtu = 68, .msgsize = 130, .n_frags = 3},
+};
+
+static void mctp_frag_test_to_desc(const struct mctp_frag_test *t, char *desc)
+{
+	sprintf(desc, "mtu %d len %d -> %d frags",
+		t->msgsize, t->mtu, t->n_frags);
+}
+
+KUNIT_ARRAY_PARAM(mctp_frag, mctp_frag_tests, mctp_frag_test_to_desc);
+
+struct mctp_rx_input_test {
+	struct mctp_hdr hdr;
+	bool input;
+};
+
+static void mctp_test_rx_input(struct kunit *test)
+{
+	const struct mctp_rx_input_test *params;
+	struct mctp_test_route *rt;
+	struct mctp_test_dev *dev;
+	struct sk_buff *skb;
+
+	params = test->param_value;
+
+	dev = mctp_test_create_dev();
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, dev);
+
+	rt = mctp_test_create_route(&init_net, dev->mdev, 8, 68);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, rt);
+
+	skb = mctp_test_create_skb(&params->hdr, 1);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, skb);
+
+	__mctp_cb(skb);
+
+	mctp_pkttype_receive(skb, dev->ndev, &mctp_packet_type, NULL);
+
+	KUNIT_EXPECT_EQ(test, !!rt->pkts.qlen, params->input);
+
+	mctp_test_route_destroy(test, rt);
+	mctp_test_destroy_dev(dev);
+}
+
+#define RX_HDR(_ver, _src, _dest, _fst) \
+	{ .ver = _ver, .src = _src, .dest = _dest, .flags_seq_tag = _fst }
+
+/* we have a route for EID 8 only */
+static const struct mctp_rx_input_test mctp_rx_input_tests[] = {
+	{ .hdr = RX_HDR(1, 10, 8, 0), .input = true },
+	{ .hdr = RX_HDR(1, 10, 9, 0), .input = false }, /* no input route */
+	{ .hdr = RX_HDR(2, 10, 8, 0), .input = false }, /* invalid version */
+};
+
+static void mctp_rx_input_test_to_desc(const struct mctp_rx_input_test *t,
+				       char *desc)
+{
+	sprintf(desc, "{%x,%x,%x,%x}", t->hdr.ver, t->hdr.src, t->hdr.dest,
+		t->hdr.flags_seq_tag);
+}
+
+KUNIT_ARRAY_PARAM(mctp_rx_input, mctp_rx_input_tests,
+		  mctp_rx_input_test_to_desc);
+
+/* set up a local dev, route on EID 8, and a socket listening on type 0 */
+static void __mctp_route_test_init(struct kunit *test,
+				   struct mctp_test_dev **devp,
+				   struct mctp_test_route **rtp,
+				   struct socket **sockp)
+{
+	struct sockaddr_mctp addr;
+	struct mctp_test_route *rt;
+	struct mctp_test_dev *dev;
+	struct socket *sock;
+	int rc;
+
+	dev = mctp_test_create_dev();
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, dev);
+
+	rt = mctp_test_create_route(&init_net, dev->mdev, 8, 68);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, rt);
+
+	rc = sock_create_kern(&init_net, AF_MCTP, SOCK_DGRAM, 0, &sock);
+	KUNIT_ASSERT_EQ(test, rc, 0);
+
+	addr.smctp_family = AF_MCTP;
+	addr.smctp_network = MCTP_NET_ANY;
+	addr.smctp_addr.s_addr = 8;
+	addr.smctp_type = 0;
+	rc = kernel_bind(sock, (struct sockaddr *)&addr, sizeof(addr));
+	KUNIT_ASSERT_EQ(test, rc, 0);
+
+	*rtp = rt;
+	*devp = dev;
+	*sockp = sock;
+}
+
+static void __mctp_route_test_fini(struct kunit *test,
+				   struct mctp_test_dev *dev,
+				   struct mctp_test_route *rt,
+				   struct socket *sock)
+{
+	sock_release(sock);
+	mctp_test_route_destroy(test, rt);
+	mctp_test_destroy_dev(dev);
+}
+
+struct mctp_route_input_sk_test {
+	struct mctp_hdr hdr;
+	u8 type;
+	bool deliver;
+};
+
+static void mctp_test_route_input_sk(struct kunit *test)
+{
+	const struct mctp_route_input_sk_test *params;
+	struct sk_buff *skb, *skb2;
+	struct mctp_test_route *rt;
+	struct mctp_test_dev *dev;
+	struct socket *sock;
+	int rc;
+
+	params = test->param_value;
+
+	__mctp_route_test_init(test, &dev, &rt, &sock);
+
+	skb = mctp_test_create_skb_data(&params->hdr, &params->type);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, skb);
+
+	skb->dev = dev->ndev;
+	__mctp_cb(skb);
+
+	rc = mctp_route_input(&rt->rt, skb);
+
+	if (params->deliver) {
+		KUNIT_EXPECT_EQ(test, rc, 0);
+
+		skb2 = skb_recv_datagram(sock->sk, 0, 1, &rc);
+		KUNIT_EXPECT_NOT_ERR_OR_NULL(test, skb2);
+		KUNIT_EXPECT_EQ(test, skb->len, 1);
+
+		skb_free_datagram(sock->sk, skb2);
+
+	} else {
+		KUNIT_EXPECT_NE(test, rc, 0);
+		skb2 = skb_recv_datagram(sock->sk, 0, 1, &rc);
+		KUNIT_EXPECT_PTR_EQ(test, skb2, NULL);
+	}
+
+	__mctp_route_test_fini(test, dev, rt, sock);
+}
+
+#define FL_S	(MCTP_HDR_FLAG_SOM)
+#define FL_E	(MCTP_HDR_FLAG_EOM)
+#define FL_T	(MCTP_HDR_FLAG_TO)
+
+static const struct mctp_route_input_sk_test mctp_route_input_sk_tests[] = {
+	{ .hdr = RX_HDR(1, 10, 8, FL_S | FL_E | FL_T), .type = 0, .deliver = true },
+	{ .hdr = RX_HDR(1, 10, 8, FL_S | FL_E | FL_T), .type = 1, .deliver = false },
+	{ .hdr = RX_HDR(1, 10, 8, FL_S | FL_E), .type = 0, .deliver = false },
+	{ .hdr = RX_HDR(1, 10, 8, FL_E | FL_T), .type = 0, .deliver = false },
+	{ .hdr = RX_HDR(1, 10, 8, FL_T), .type = 0, .deliver = false },
+	{ .hdr = RX_HDR(1, 10, 8, 0), .type = 0, .deliver = false },
+};
+
+static void mctp_route_input_sk_to_desc(const struct mctp_route_input_sk_test *t,
+					char *desc)
+{
+	sprintf(desc, "{%x,%x,%x,%x} type %d", t->hdr.ver, t->hdr.src,
+		t->hdr.dest, t->hdr.flags_seq_tag, t->type);
+}
+
+KUNIT_ARRAY_PARAM(mctp_route_input_sk, mctp_route_input_sk_tests,
+		  mctp_route_input_sk_to_desc);
+
+struct mctp_route_input_sk_reasm_test {
+	const char *name;
+	struct mctp_hdr hdrs[4];
+	int n_hdrs;
+	int rx_len;
+};
+
+static void mctp_test_route_input_sk_reasm(struct kunit *test)
+{
+	const struct mctp_route_input_sk_reasm_test *params;
+	struct sk_buff *skb, *skb2;
+	struct mctp_test_route *rt;
+	struct mctp_test_dev *dev;
+	struct socket *sock;
+	int i, rc;
+	u8 c;
+
+	params = test->param_value;
+
+	__mctp_route_test_init(test, &dev, &rt, &sock);
+
+	for (i = 0; i < params->n_hdrs; i++) {
+		c = i;
+		skb = mctp_test_create_skb_data(&params->hdrs[i], &c);
+		KUNIT_ASSERT_NOT_ERR_OR_NULL(test, skb);
+
+		skb->dev = dev->ndev;
+		__mctp_cb(skb);
+
+		rc = mctp_route_input(&rt->rt, skb);
+	}
+
+	skb2 = skb_recv_datagram(sock->sk, 0, 1, &rc);
+
+	if (params->rx_len) {
+		KUNIT_EXPECT_NOT_ERR_OR_NULL(test, skb2);
+		KUNIT_EXPECT_EQ(test, skb2->len, params->rx_len);
+		skb_free_datagram(sock->sk, skb2);
+
+	} else {
+		KUNIT_EXPECT_PTR_EQ(test, skb2, NULL);
+	}
+
+	__mctp_route_test_fini(test, dev, rt, sock);
+}
+
+#define RX_FRAG(f, s) RX_HDR(1, 10, 8, FL_T | (f) | ((s) << MCTP_HDR_SEQ_SHIFT))
+
+static const struct mctp_route_input_sk_reasm_test mctp_route_input_sk_reasm_tests[] = {
+	{
+		.name = "single packet",
+		.hdrs = {
+			RX_FRAG(FL_S | FL_E, 0),
+		},
+		.n_hdrs = 1,
+		.rx_len = 1,
+	},
+	{
+		.name = "single packet, offset seq",
+		.hdrs = {
+			RX_FRAG(FL_S | FL_E, 1),
+		},
+		.n_hdrs = 1,
+		.rx_len = 1,
+	},
+	{
+		.name = "start & end packets",
+		.hdrs = {
+			RX_FRAG(FL_S, 0),
+			RX_FRAG(FL_E, 1),
+		},
+		.n_hdrs = 2,
+		.rx_len = 2,
+	},
+	{
+		.name = "start & end packets, offset seq",
+		.hdrs = {
+			RX_FRAG(FL_S, 1),
+			RX_FRAG(FL_E, 2),
+		},
+		.n_hdrs = 2,
+		.rx_len = 2,
+	},
+	{
+		.name = "start & end packets, out of order",
+		.hdrs = {
+			RX_FRAG(FL_E, 1),
+			RX_FRAG(FL_S, 0),
+		},
+		.n_hdrs = 2,
+		.rx_len = 0,
+	},
+	{
+		.name = "start, middle & end packets",
+		.hdrs = {
+			RX_FRAG(FL_S, 0),
+			RX_FRAG(0,    1),
+			RX_FRAG(FL_E, 2),
+		},
+		.n_hdrs = 3,
+		.rx_len = 3,
+	},
+	{
+		.name = "missing seq",
+		.hdrs = {
+			RX_FRAG(FL_S, 0),
+			RX_FRAG(FL_E, 2),
+		},
+		.n_hdrs = 2,
+		.rx_len = 0,
+	},
+	{
+		.name = "seq wrap",
+		.hdrs = {
+			RX_FRAG(FL_S, 3),
+			RX_FRAG(FL_E, 0),
+		},
+		.n_hdrs = 2,
+		.rx_len = 2,
+	},
+};
+
+static void mctp_route_input_sk_reasm_to_desc(
+				const struct mctp_route_input_sk_reasm_test *t,
+				char *desc)
+{
+	sprintf(desc, "%s", t->name);
+}
+
+KUNIT_ARRAY_PARAM(mctp_route_input_sk_reasm, mctp_route_input_sk_reasm_tests,
+		  mctp_route_input_sk_reasm_to_desc);
+
+static struct kunit_case mctp_test_cases[] = {
+	KUNIT_CASE_PARAM(mctp_test_fragment, mctp_frag_gen_params),
+	KUNIT_CASE_PARAM(mctp_test_rx_input, mctp_rx_input_gen_params),
+	KUNIT_CASE_PARAM(mctp_test_route_input_sk, mctp_route_input_sk_gen_params),
+	KUNIT_CASE_PARAM(mctp_test_route_input_sk_reasm,
+			 mctp_route_input_sk_reasm_gen_params),
+	{}
+};
+
+static struct kunit_suite mctp_test_suite = {
+	.name = "mctp",
+	.test_cases = mctp_test_cases,
+};
+
+kunit_test_suite(mctp_test_suite);

net/mctp/test/utils.c

+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/netdevice.h>
+#include <linux/mctp.h>
+#include <linux/if_arp.h>
+
+#include <net/mctpdevice.h>
+#include <net/pkt_sched.h>
+
+#include "utils.h"
+
+static netdev_tx_t mctp_test_dev_tx(struct sk_buff *skb,
+				    struct net_device *ndev)
+{
+	kfree(skb);
+	return NETDEV_TX_OK;
+}
+
+static const struct net_device_ops mctp_test_netdev_ops = {
+	.ndo_start_xmit = mctp_test_dev_tx,
+};
+
+static void mctp_test_dev_setup(struct net_device *ndev)
+{
+	ndev->type = ARPHRD_MCTP;
+	ndev->mtu = MCTP_DEV_TEST_MTU;
+	ndev->hard_header_len = 0;
+	ndev->addr_len = 0;
+	ndev->tx_queue_len = DEFAULT_TX_QUEUE_LEN;
+	ndev->flags = IFF_NOARP;
+	ndev->netdev_ops = &mctp_test_netdev_ops;
+	ndev->needs_free_netdev = true;
+}
+
+struct mctp_test_dev *mctp_test_create_dev(void)
+{
+	struct mctp_test_dev *dev;
+	struct net_device *ndev;
+	int rc;
+
+	ndev = alloc_netdev(sizeof(*dev), "mctptest%d", NET_NAME_ENUM,
+			    mctp_test_dev_setup);
+	if (!ndev)
+		return NULL;
+
+	dev = netdev_priv(ndev);
+	dev->ndev = ndev;
+
+	rc = register_netdev(ndev);
+	if (rc) {
+		free_netdev(ndev);
+		return NULL;
+	}
+
+	rcu_read_lock();
+	dev->mdev = __mctp_dev_get(ndev);
+	mctp_dev_hold(dev->mdev);
+	rcu_read_unlock();
+
+	return dev;
+}
+
+void mctp_test_destroy_dev(struct mctp_test_dev *dev)
+{
+	mctp_dev_put(dev->mdev);
+	unregister_netdev(dev->ndev);
+}

net/mctp/test/utils.h

+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __NET_MCTP_TEST_UTILS_H
+#define __NET_MCTP_TEST_UTILS_H
+
+#include <kunit/test.h>
+
+#define MCTP_DEV_TEST_MTU	68
+
+struct mctp_test_dev {
+	struct net_device *ndev;
+	struct mctp_dev *mdev;
+};
+
+struct mctp_test_dev;
+
+struct mctp_test_dev *mctp_test_create_dev(void);
+void mctp_test_destroy_dev(struct mctp_test_dev *dev);
+
+#endif /* __NET_MCTP_TEST_UTILS_H */