tools/testing/selftests/bpf/prog_tests/kfree_skb.c

   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 }