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// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2020 Facebook */
#include <test_progs.h>
#include <bpf/btf.h>
/* real layout and sizes according to test's (32-bit) BTF
* needs to be defined before skeleton is included */
struct test_struct___real {
unsigned int ptr; /* can't use `void *`, it is always 8 byte in BPF target */
unsigned int val2;
unsigned long long val1;
unsigned short val3;
unsigned char val4;
unsigned char _pad;
};
#include "test_core_autosize.skel.h"
static int duration = 0;
static struct {
unsigned long long ptr_samesized;
unsigned long long val1_samesized;
unsigned long long val2_samesized;
unsigned long long val3_samesized;
unsigned long long val4_samesized;
struct test_struct___real output_samesized;
unsigned long long ptr_downsized;
unsigned long long val1_downsized;
unsigned long long val2_downsized;
unsigned long long val3_downsized;
unsigned long long val4_downsized;
struct test_struct___real output_downsized;
unsigned long long ptr_probed;
unsigned long long val1_probed;
unsigned long long val2_probed;
unsigned long long val3_probed;
unsigned long long val4_probed;
unsigned long long ptr_signed;
unsigned long long val1_signed;
unsigned long long val2_signed;
unsigned long long val3_signed;
unsigned long long val4_signed;
struct test_struct___real output_signed;
} out;
void test_core_autosize(void)
{
char btf_file[] = "/tmp/core_autosize.btf.XXXXXX";
int err, fd = -1, zero = 0;
int char_id, short_id, int_id, long_long_id, void_ptr_id, id;
struct test_core_autosize* skel = NULL;
struct bpf_object_load_attr load_attr = {};
struct bpf_program *prog;
struct bpf_map *bss_map;
struct btf *btf = NULL;
size_t written;
const void *raw_data;
__u32 raw_sz;
FILE *f = NULL;
btf = btf__new_empty();
if (!ASSERT_OK_PTR(btf, "empty_btf"))
return;
/* Emit the following struct with 32-bit pointer size:
*
* struct test_struct {
* void *ptr;
* unsigned long val2;
* unsigned long long val1;
* unsigned short val3;
* unsigned char val4;
* char: 8;
* };
*
* This struct is going to be used as the "kernel BTF" for this test.
* It's equivalent memory-layout-wise to test_struct__real above.
*/
/* force 32-bit pointer size */
btf__set_pointer_size(btf, 4);
char_id = btf__add_int(btf, "unsigned char", 1, 0);
ASSERT_EQ(char_id, 1, "char_id");
short_id = btf__add_int(btf, "unsigned short", 2, 0);
ASSERT_EQ(short_id, 2, "short_id");
/* "long unsigned int" of 4 byte size tells BTF that sizeof(void *) == 4 */
int_id = btf__add_int(btf, "long unsigned int", 4, 0);
ASSERT_EQ(int_id, 3, "int_id");
long_long_id = btf__add_int(btf, "unsigned long long", 8, 0);
ASSERT_EQ(long_long_id, 4, "long_long_id");
void_ptr_id = btf__add_ptr(btf, 0);
ASSERT_EQ(void_ptr_id, 5, "void_ptr_id");
id = btf__add_struct(btf, "test_struct", 20 /* bytes */);
ASSERT_EQ(id, 6, "struct_id");
err = btf__add_field(btf, "ptr", void_ptr_id, 0, 0);
err = err ?: btf__add_field(btf, "val2", int_id, 32, 0);
err = err ?: btf__add_field(btf, "val1", long_long_id, 64, 0);
err = err ?: btf__add_field(btf, "val3", short_id, 128, 0);
err = err ?: btf__add_field(btf, "val4", char_id, 144, 0);
ASSERT_OK(err, "struct_fields");
fd = mkstemp(btf_file);
if (CHECK(fd < 0, "btf_tmp", "failed to create file: %d\n", fd))
goto cleanup;
f = fdopen(fd, "w");
if (!ASSERT_OK_PTR(f, "btf_fdopen"))
goto cleanup;
raw_data = btf__get_raw_data(btf, &raw_sz);
if (!ASSERT_OK_PTR(raw_data, "raw_data"))
goto cleanup;
written = fwrite(raw_data, 1, raw_sz, f);
if (CHECK(written != raw_sz, "btf_write", "written: %zu, errno: %d\n", written, errno))
goto cleanup;
fflush(f);
fclose(f);
f = NULL;
close(fd);
fd = -1;
/* open and load BPF program with custom BTF as the kernel BTF */
skel = test_core_autosize__open();
if (!ASSERT_OK_PTR(skel, "skel_open"))
return;
/* disable handle_signed() for now */
prog = bpf_object__find_program_by_name(skel->obj, "handle_signed");
if (!ASSERT_OK_PTR(prog, "prog_find"))
goto cleanup;
bpf_program__set_autoload(prog, false);
load_attr.obj = skel->obj;
load_attr.target_btf_path = btf_file;
err = bpf_object__load_xattr(&load_attr);
if (!ASSERT_OK(err, "prog_load"))
goto cleanup;
prog = bpf_object__find_program_by_name(skel->obj, "handle_samesize");
if (!ASSERT_OK_PTR(prog, "prog_find"))
goto cleanup;
skel->links.handle_samesize = bpf_program__attach(prog);
if (!ASSERT_OK_PTR(skel->links.handle_samesize, "prog_attach"))
goto cleanup;
prog = bpf_object__find_program_by_name(skel->obj, "handle_downsize");
if (!ASSERT_OK_PTR(prog, "prog_find"))
goto cleanup;
skel->links.handle_downsize = bpf_program__attach(prog);
if (!ASSERT_OK_PTR(skel->links.handle_downsize, "prog_attach"))
goto cleanup;
prog = bpf_object__find_program_by_name(skel->obj, "handle_probed");
if (!ASSERT_OK_PTR(prog, "prog_find"))
goto cleanup;
skel->links.handle_probed = bpf_program__attach(prog);
if (!ASSERT_OK_PTR(skel->links.handle_probed, "prog_attach"))
goto cleanup;
usleep(1);
bss_map = bpf_object__find_map_by_name(skel->obj, "test_cor.bss");
if (!ASSERT_OK_PTR(bss_map, "bss_map_find"))
goto cleanup;
err = bpf_map_lookup_elem(bpf_map__fd(bss_map), &zero, (void *)&out);
if (!ASSERT_OK(err, "bss_lookup"))
goto cleanup;
ASSERT_EQ(out.ptr_samesized, 0x01020304, "ptr_samesized");
ASSERT_EQ(out.val1_samesized, 0x1020304050607080, "val1_samesized");
ASSERT_EQ(out.val2_samesized, 0x0a0b0c0d, "val2_samesized");
ASSERT_EQ(out.val3_samesized, 0xfeed, "val3_samesized");
ASSERT_EQ(out.val4_samesized, 0xb9, "val4_samesized");
ASSERT_EQ(out.output_samesized.ptr, 0x01020304, "ptr_samesized");
ASSERT_EQ(out.output_samesized.val1, 0x1020304050607080, "val1_samesized");
ASSERT_EQ(out.output_samesized.val2, 0x0a0b0c0d, "val2_samesized");
ASSERT_EQ(out.output_samesized.val3, 0xfeed, "val3_samesized");
ASSERT_EQ(out.output_samesized.val4, 0xb9, "val4_samesized");
ASSERT_EQ(out.ptr_downsized, 0x01020304, "ptr_downsized");
ASSERT_EQ(out.val1_downsized, 0x1020304050607080, "val1_downsized");
ASSERT_EQ(out.val2_downsized, 0x0a0b0c0d, "val2_downsized");
ASSERT_EQ(out.val3_downsized, 0xfeed, "val3_downsized");
ASSERT_EQ(out.val4_downsized, 0xb9, "val4_downsized");
ASSERT_EQ(out.output_downsized.ptr, 0x01020304, "ptr_downsized");
ASSERT_EQ(out.output_downsized.val1, 0x1020304050607080, "val1_downsized");
ASSERT_EQ(out.output_downsized.val2, 0x0a0b0c0d, "val2_downsized");
ASSERT_EQ(out.output_downsized.val3, 0xfeed, "val3_downsized");
ASSERT_EQ(out.output_downsized.val4, 0xb9, "val4_downsized");
ASSERT_EQ(out.ptr_probed, 0x01020304, "ptr_probed");
ASSERT_EQ(out.val1_probed, 0x1020304050607080, "val1_probed");
ASSERT_EQ(out.val2_probed, 0x0a0b0c0d, "val2_probed");
ASSERT_EQ(out.val3_probed, 0xfeed, "val3_probed");
ASSERT_EQ(out.val4_probed, 0xb9, "val4_probed");
test_core_autosize__destroy(skel);
skel = NULL;
/* now re-load with handle_signed() enabled, it should fail loading */
skel = test_core_autosize__open();
if (!ASSERT_OK_PTR(skel, "skel_open"))
return;
load_attr.obj = skel->obj;
load_attr.target_btf_path = btf_file;
err = bpf_object__load_xattr(&load_attr);
if (!ASSERT_ERR(err, "bad_prog_load"))
goto cleanup;
cleanup:
if (f)
fclose(f);
if (fd >= 0)
close(fd);
remove(btf_file);
btf__free(
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