1 // SPDX-License-Identifier: GPL-2.0
2 #define _GNU_SOURCE
3 #include <test_progs.h>
4 #include <network_helpers.h>
5 #include "kfree_skb.skel.h"
6 
7 struct meta {
8 	int ifindex;
9 	__u32 cb32_0;
10 	__u8 cb8_0;
11 };
12 
13 static union {
14 	__u32 cb32[5];
15 	__u8 cb8[20];
16 } cb = {
17 	.cb32[0] = 0x81828384,
18 };
19 
20 static void on_sample(void *ctx, int cpu, void *data, __u32 size)
21 {
22 	struct meta *meta = (struct meta *)data;
23 	struct ipv6_packet *pkt_v6 = data + sizeof(*meta);
24 	int duration = 0;
25 
26 	if (CHECK(size != 72 + sizeof(*meta), "check_size", "size %u != %zu\n",
27 		  size, 72 + sizeof(*meta)))
28 		return;
29 	if (CHECK(meta->ifindex != 1, "check_meta_ifindex",
30 		  "meta->ifindex = %d\n", meta->ifindex))
31 		/* spurious kfree_skb not on loopback device */
32 		return;
33 	if (CHECK(meta->cb8_0 != cb.cb8[0], "check_cb8_0", "cb8_0 %x != %x\n",
34 		  meta->cb8_0, cb.cb8[0]))
35 		return;
36 	if (CHECK(meta->cb32_0 != cb.cb32[0], "check_cb32_0",
37 		  "cb32_0 %x != %x\n",
38 		  meta->cb32_0, cb.cb32[0]))
39 		return;
40 	if (CHECK(pkt_v6->eth.h_proto != htons(ETH_P_IPV6), "check_eth",
41 		  "h_proto %x\n", pkt_v6->eth.h_proto))
42 		return;
43 	if (CHECK(pkt_v6->iph.nexthdr != 6, "check_ip",
44 		  "iph.nexthdr %x\n", pkt_v6->iph.nexthdr))
45 		return;
46 	if (CHECK(pkt_v6->tcp.doff != 5, "check_tcp",
47 		  "tcp.doff %x\n", pkt_v6->tcp.doff))
48 		return;
49 
50 	*(bool *)ctx = true;
51 }
52 
53 /* TODO: fix kernel panic caused by this test in parallel mode */
54 void serial_test_kfree_skb(void)
55 {
56 	struct __sk_buff skb = {};
57 	LIBBPF_OPTS(bpf_test_run_opts, topts,
58 		.data_in = &pkt_v6,
59 		.data_size_in = sizeof(pkt_v6),
60 		.ctx_in = &skb,
61 		.ctx_size_in = sizeof(skb),
62 	);
63 	struct kfree_skb *skel = NULL;
64 	struct bpf_link *link;
65 	struct bpf_object *obj;
66 	struct perf_buffer *pb = NULL;
67 	int err, prog_fd;
68 	bool passed = false;
69 	__u32 duration = 0;
70 	const int zero = 0;
71 	bool test_ok[2];
72 
73 	err = bpf_prog_test_load("./test_pkt_access.bpf.o", BPF_PROG_TYPE_SCHED_CLS,
74 				 &obj, &prog_fd);
75 	if (CHECK(err, "prog_load sched cls", "err %d errno %d\n", err, errno))
76 		return;
77 
78 	skel = kfree_skb__open_and_load();
79 	if (!ASSERT_OK_PTR(skel, "kfree_skb_skel"))
80 		goto close_prog;
81 
82 	link = bpf_program__attach_raw_tracepoint(skel->progs.trace_kfree_skb, NULL);
83 	if (!ASSERT_OK_PTR(link, "attach_raw_tp"))
84 		goto close_prog;
85 	skel->links.trace_kfree_skb = link;
86 
87 	link = bpf_program__attach_trace(skel->progs.fentry_eth_type_trans);
88 	if (!ASSERT_OK_PTR(link, "attach fentry"))
89 		goto close_prog;
90 	skel->links.fentry_eth_type_trans = link;
91 
92 	link = bpf_program__attach_trace(skel->progs.fexit_eth_type_trans);
93 	if (!ASSERT_OK_PTR(link, "attach fexit"))
94 		goto close_prog;
95 	skel->links.fexit_eth_type_trans = link;
96 
97 	/* set up perf buffer */
98 	pb = perf_buffer__new(bpf_map__fd(skel->maps.perf_buf_map), 1,
99 			      on_sample, NULL, &passed, NULL);
100 	if (!ASSERT_OK_PTR(pb, "perf_buf__new"))
101 		goto close_prog;
102 
103 	memcpy(skb.cb, &cb, sizeof(cb));
104 	err = bpf_prog_test_run_opts(prog_fd, &topts);
105 	ASSERT_OK(err, "ipv6 test_run");
106 	ASSERT_OK(topts.retval, "ipv6 test_run retval");
107 
108 	/* read perf buffer */
109 	err = perf_buffer__poll(pb, 100);
110 	if (CHECK(err < 0, "perf_buffer__poll", "err %d\n", err))
111 		goto close_prog;
112 
113 	/* make sure kfree_skb program was triggered
114 	 * and it sent expected skb into ring buffer
115 	 */
116 	ASSERT_TRUE(passed, "passed");
117 
118 	err = bpf_map_lookup_elem(bpf_map__fd(skel->maps.bss), &zero, test_ok);
119 	if (CHECK(err, "get_result",
120 		  "failed to get output data: %d\n", err))
121 		goto close_prog;
122 
123 	CHECK_FAIL(!test_ok[0] || !test_ok[1]);
124 close_prog:
125 	perf_buffer__free(pb);
126 	bpf_object__close(obj);
127 	kfree_skb__destroy(skel);
128 }
129