1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * bpf-script-test-relocation.c
4 * Test BPF loader checking relocation
5 */
6 #ifndef LINUX_VERSION_CODE
7 # error Need LINUX_VERSION_CODE
8 # error Example: for 4.2 kernel, put 'clang-opt="-DLINUX_VERSION_CODE=0x40200" into llvm section of ~/.perfconfig'
9 #endif
10 #define BPF_ANY 0
11 #define BPF_MAP_TYPE_ARRAY 2
12 #define BPF_FUNC_map_lookup_elem 1
13 #define BPF_FUNC_map_update_elem 2
14
15 static void *(*bpf_map_lookup_elem)(void *map, void *key) =
16 (void *) BPF_FUNC_map_lookup_elem;
17 static void *(*bpf_map_update_elem)(void *map, void *key, void *value, int flags) =
18 (void *) BPF_FUNC_map_update_elem;
19
20 struct bpf_map_def {
21 unsigned int type;
22 unsigned int key_size;
23 unsigned int value_size;
24 unsigned int max_entries;
25 };
26
27 #define SEC(NAME) __attribute__((section(NAME), used))
28 struct bpf_map_def SEC("maps") my_table = {
29 .type = BPF_MAP_TYPE_ARRAY,
30 .key_size = sizeof(int),
31 .value_size = sizeof(int),
32 .max_entries = 1,
33 };
34
35 int this_is_a_global_val;
36
37 SEC("func=sys_write")
bpf_func__sys_write(void * ctx)38 int bpf_func__sys_write(void *ctx)
39 {
40 int key = 0;
41 int value = 0;
42
43 /*
44 * Incorrect relocation. Should not allow this program be
45 * loaded into kernel.
46 */
47 bpf_map_update_elem(&this_is_a_global_val, &key, &value, 0);
48 return 0;
49 }
50 char _license[] SEC("license") = "GPL";
51 int _version SEC("version") = LINUX_VERSION_CODE;
52