1 files changed, 195 insertions, 0 deletions

diff --git a/net/mctp/test/route-test.c b/net/mctp/test/route-test.c
index 8551dab1d1e6..06c1897b685a 100644
--- a/net/mctp/test/route-test.c
+++ b/net/mctp/test/route-test.c
@@ -837,6 +837,198 @@ static void mctp_test_route_input_multiple_nets_key(struct kunit *test)
 	mctp_test_route_input_multiple_nets_key_fini(test, &t2);
 }
 
+/* Input route to socket, using a single-packet message, where sock delivery
+ * fails. Ensure we're handling the failure appropriately.
+ */
+static void mctp_test_route_input_sk_fail_single(struct kunit *test)
+{
+	const struct mctp_hdr hdr = RX_HDR(1, 10, 8, FL_S | FL_E | FL_TO);
+	struct mctp_test_route *rt;
+	struct mctp_test_dev *dev;
+	struct socket *sock;
+	struct sk_buff *skb;
+	int rc;
+
+	__mctp_route_test_init(test, &dev, &rt, &sock, MCTP_NET_ANY);
+
+	/* No rcvbuf space, so delivery should fail. __sock_set_rcvbuf will
+	 * clamp the minimum to SOCK_MIN_RCVBUF, so we open-code this.
+	 */
+	lock_sock(sock->sk);
+	WRITE_ONCE(sock->sk->sk_rcvbuf, 0);
+	release_sock(sock->sk);
+
+	skb = mctp_test_create_skb(&hdr, 10);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, skb);
+	skb_get(skb);
+
+	mctp_test_skb_set_dev(skb, dev);
+
+	/* do route input, which should fail */
+	rc = mctp_route_input(&rt->rt, skb);
+	KUNIT_EXPECT_NE(test, rc, 0);
+
+	/* we should hold the only reference to skb */
+	KUNIT_EXPECT_EQ(test, refcount_read(&skb->users), 1);
+	kfree_skb(skb);
+
+	__mctp_route_test_fini(test, dev, rt, sock);
+}
+
+/* Input route to socket, using a fragmented message, where sock delivery fails.
+ */
+static void mctp_test_route_input_sk_fail_frag(struct kunit *test)
+{
+	const struct mctp_hdr hdrs[2] = { RX_FRAG(FL_S, 0), RX_FRAG(FL_E, 1) };
+	struct mctp_test_route *rt;
+	struct mctp_test_dev *dev;
+	struct sk_buff *skbs[2];
+	struct socket *sock;
+	unsigned int i;
+	int rc;
+
+	__mctp_route_test_init(test, &dev, &rt, &sock, MCTP_NET_ANY);
+
+	lock_sock(sock->sk);
+	WRITE_ONCE(sock->sk->sk_rcvbuf, 0);
+	release_sock(sock->sk);
+
+	for (i = 0; i < ARRAY_SIZE(skbs); i++) {
+		skbs[i] = mctp_test_create_skb(&hdrs[i], 10);
+		KUNIT_ASSERT_NOT_ERR_OR_NULL(test, skbs[i]);
+		skb_get(skbs[i]);
+
+		mctp_test_skb_set_dev(skbs[i], dev);
+	}
+
+	/* first route input should succeed, we're only queueing to the
+	 * frag list
+	 */
+	rc = mctp_route_input(&rt->rt, skbs[0]);
+	KUNIT_EXPECT_EQ(test, rc, 0);
+
+	/* final route input should fail to deliver to the socket */
+	rc = mctp_route_input(&rt->rt, skbs[1]);
+	KUNIT_EXPECT_NE(test, rc, 0);
+
+	/* we should hold the only reference to both skbs */
+	KUNIT_EXPECT_EQ(test, refcount_read(&skbs[0]->users), 1);
+	kfree_skb(skbs[0]);
+
+	KUNIT_EXPECT_EQ(test, refcount_read(&skbs[1]->users), 1);
+	kfree_skb(skbs[1]);
+
+	__mctp_route_test_fini(test, dev, rt, sock);
+}
+
+/* Input route to socket, using a fragmented message created from clones.
+ */
+static void mctp_test_route_input_cloned_frag(struct kunit *test)
+{
+	/* 5 packet fragments, forming 2 complete messages */
+	const struct mctp_hdr hdrs[5] = {
+		RX_FRAG(FL_S, 0),
+		RX_FRAG(0, 1),
+		RX_FRAG(FL_E, 2),
+		RX_FRAG(FL_S, 0),
+		RX_FRAG(FL_E, 1),
+	};
+	struct mctp_test_route *rt;
+	struct mctp_test_dev *dev;
+	struct sk_buff *skb[5];
+	struct sk_buff *rx_skb;
+	struct socket *sock;
+	size_t data_len;
+	u8 compare[100];
+	u8 flat[100];
+	size_t total;
+	void *p;
+	int rc;
+
+	/* Arbitrary length */
+	data_len = 3;
+	total = data_len + sizeof(struct mctp_hdr);
+
+	__mctp_route_test_init(test, &dev, &rt, &sock, MCTP_NET_ANY);
+
+	/* Create a single skb initially with concatenated packets */
+	skb[0] = mctp_test_create_skb(&hdrs[0], 5 * total);
+	mctp_test_skb_set_dev(skb[0], dev);
+	memset(skb[0]->data, 0 * 0x11, skb[0]->len);
+	memcpy(skb[0]->data, &hdrs[0], sizeof(struct mctp_hdr));
+
+	/* Extract and populate packets */
+	for (int i = 1; i < 5; i++) {
+		skb[i] = skb_clone(skb[i - 1], GFP_ATOMIC);
+		KUNIT_ASSERT_TRUE(test, skb[i]);
+		p = skb_pull(skb[i], total);
+		KUNIT_ASSERT_TRUE(test, p);
+		skb_reset_network_header(skb[i]);
+		memcpy(skb[i]->data, &hdrs[i], sizeof(struct mctp_hdr));
+		memset(&skb[i]->data[sizeof(struct mctp_hdr)], i * 0x11, data_len);
+	}
+	for (int i = 0; i < 5; i++)
+		skb_trim(skb[i], total);
+
+	/* SOM packets have a type byte to match the socket */
+	skb[0]->data[4] = 0;
+	skb[3]->data[4] = 0;
+
+	skb_dump("pkt1 ", skb[0], false);
+	skb_dump("pkt2 ", skb[1], false);
+	skb_dump("pkt3 ", skb[2], false);
+	skb_dump("pkt4 ", skb[3], false);
+	skb_dump("pkt5 ", skb[4], false);
+
+	for (int i = 0; i < 5; i++) {
+		KUNIT_EXPECT_EQ(test, refcount_read(&skb[i]->users), 1);
+		/* Take a reference so we can check refcounts at the end */
+		skb_get(skb[i]);
+	}
+
+	/* Feed the fragments into MCTP core */
+	for (int i = 0; i < 5; i++) {
+		rc = mctp_route_input(&rt->rt, skb[i]);
+		KUNIT_EXPECT_EQ(test, rc, 0);
+	}
+
+	/* Receive first reassembled message */
+	rx_skb = skb_recv_datagram(sock->sk, MSG_DONTWAIT, &rc);
+	KUNIT_EXPECT_EQ(test, rc, 0);
+	KUNIT_EXPECT_EQ(test, rx_skb->len, 3 * data_len);
+	rc = skb_copy_bits(rx_skb, 0, flat, rx_skb->len);
+	for (int i = 0; i < rx_skb->len; i++)
+		compare[i] = (i / data_len) * 0x11;
+	/* Set type byte */
+	compare[0] = 0;
+
+	KUNIT_EXPECT_MEMEQ(test, flat, compare, rx_skb->len);
+	KUNIT_EXPECT_EQ(test, refcount_read(&rx_skb->users), 1);
+	kfree_skb(rx_skb);
+
+	/* Receive second reassembled message */
+	rx_skb = skb_recv_datagram(sock->sk, MSG_DONTWAIT, &rc);
+	KUNIT_EXPECT_EQ(test, rc, 0);
+	KUNIT_EXPECT_EQ(test, rx_skb->len, 2 * data_len);
+	rc = skb_copy_bits(rx_skb, 0, flat, rx_skb->len);
+	for (int i = 0; i < rx_skb->len; i++)
+		compare[i] = (i / data_len + 3) * 0x11;
+	/* Set type byte */
+	compare[0] = 0;
+
+	KUNIT_EXPECT_MEMEQ(test, flat, compare, rx_skb->len);
+	KUNIT_EXPECT_EQ(test, refcount_read(&rx_skb->users), 1);
+	kfree_skb(rx_skb);
+
+	/* Check input skb refcounts */
+	for (int i = 0; i < 5; i++) {
+		KUNIT_EXPECT_EQ(test, refcount_read(&skb[i]->users), 1);
+		kfree_skb(skb[i]);
+	}
+
+	__mctp_route_test_fini(test, dev, rt, sock);
+}
+
 #if IS_ENABLED(CONFIG_MCTP_FLOWS)
 
 static void mctp_test_flow_init(struct kunit *test,
@@ -1053,11 +1245,14 @@ static struct kunit_case mctp_test_cases[] = {
 			 mctp_route_input_sk_reasm_gen_params),
 	KUNIT_CASE_PARAM(mctp_test_route_input_sk_keys,
 			 mctp_route_input_sk_keys_gen_params),
+	KUNIT_CASE(mctp_test_route_input_sk_fail_single),
+	KUNIT_CASE(mctp_test_route_input_sk_fail_frag),
 	KUNIT_CASE(mctp_test_route_input_multiple_nets_bind),
 	KUNIT_CASE(mctp_test_route_input_multiple_nets_key),
 	KUNIT_CASE(mctp_test_packet_flow),
 	KUNIT_CASE(mctp_test_fragment_flow),
 	KUNIT_CASE(mctp_test_route_output_key_create),
+	KUNIT_CASE(mctp_test_route_input_cloned_frag),
 	{}
 };