1  // SPDX-License-Identifier: GPL-2.0
2  /* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */
3  
4  #include "vmlinux.h"
5  #include <bpf/bpf_helpers.h>
6  #include <bpf/bpf_tracing.h>
7  
8  char _license[] SEC("license") = "GPL";
9  
10  /* rodata section */
11  const volatile pid_t pid;
12  const volatile size_t bss_array_len;
13  const volatile size_t data_array_len;
14  
15  /* bss section */
16  int sum = 0;
17  int array[1];
18  
19  /* custom data section */
20  int my_array[1] SEC(".data.custom");
21  
22  /* custom data section which should NOT be resizable,
23   * since it contains a single var which is not an array
24   */
25  int my_int SEC(".data.non_array");
26  
27  /* custom data section which should NOT be resizable,
28   * since its last var is not an array
29   */
30  int my_array_first[1] SEC(".data.array_not_last");
31  int my_int_last SEC(".data.array_not_last");
32  
33  int percpu_arr[1] SEC(".data.percpu_arr");
34  
35  SEC("tp/syscalls/sys_enter_getpid")
bss_array_sum(void * ctx)36  int bss_array_sum(void *ctx)
37  {
38  	if (pid != (bpf_get_current_pid_tgid() >> 32))
39  		return 0;
40  
41  	/* this will be zero, we just rely on verifier not rejecting this */
42  	sum = percpu_arr[bpf_get_smp_processor_id()];
43  
44  	for (size_t i = 0; i < bss_array_len; ++i)
45  		sum += array[i];
46  
47  	return 0;
48  }
49  
50  SEC("tp/syscalls/sys_enter_getuid")
data_array_sum(void * ctx)51  int data_array_sum(void *ctx)
52  {
53  	if (pid != (bpf_get_current_pid_tgid() >> 32))
54  		return 0;
55  
56  	/* this will be zero, we just rely on verifier not rejecting this */
57  	sum = percpu_arr[bpf_get_smp_processor_id()];
58  
59  	for (size_t i = 0; i < data_array_len; ++i)
60  		sum += my_array[i];
61  
62  	return 0;
63  }
64  
65  SEC("struct_ops/test_1")
BPF_PROG(test_1)66  int BPF_PROG(test_1)
67  {
68  	return 0;
69  }
70  
71  struct bpf_testmod_ops {
72  	int (*test_1)(void);
73  };
74  
75  SEC(".struct_ops.link")
76  struct bpf_testmod_ops st_ops_resize = {
77  	.test_1 = (void *)test_1
78  };
79