LXR linux/tools/perf/tests/bpf-script-test-relocation.c

   1/*
   2 * bpf-script-test-relocation.c
   3 * Test BPF loader checking relocation
   4 */
   5#ifndef LINUX_VERSION_CODE
   6# error Need LINUX_VERSION_CODE
   7# error Example: for 4.2 kernel, put 'clang-opt="-DLINUX_VERSION_CODE=0x40200" into llvm section of ~/.perfconfig'
   8#endif
   9#define BPF_ANY 0
  10#define BPF_MAP_TYPE_ARRAY 2
  11#define BPF_FUNC_map_lookup_elem 1
  12#define BPF_FUNC_map_update_elem 2
  13
  14static void *(*bpf_map_lookup_elem)(void *map, void *key) =
  15        (void *) BPF_FUNC_map_lookup_elem;
  16static void *(*bpf_map_update_elem)(void *map, void *key, void *value, int flags) =
  17        (void *) BPF_FUNC_map_update_elem;
  18
  19struct bpf_map_def {
  20        unsigned int type;
  21        unsigned int key_size;
  22        unsigned int value_size;
  23        unsigned int max_entries;
  24};
  25
  26#define SEC(NAME) __attribute__((section(NAME), used))
  27struct bpf_map_def SEC("maps") my_table = {
  28        .type = BPF_MAP_TYPE_ARRAY,
  29        .key_size = sizeof(int),
  30        .value_size = sizeof(int),
  31        .max_entries = 1,
  32};
  33
  34int this_is_a_global_val;
  35
  36SEC("func=sys_write")
  37int bpf_func__sys_write(void *ctx)
  38{
  39        int key = 0;
  40        int value = 0;
  41
  42        /*
  43         * Incorrect relocation. Should not allow this program be
  44         * loaded into kernel.
  45         */
  46        bpf_map_update_elem(&this_is_a_global_val, &key, &value, 0);
  47        return 0;
  48}
  49char _license[] SEC("license") = "GPL";
  50int _version SEC("version") = LINUX_VERSION_CODE;
  51