mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-11-24 02:50:53 +07:00
selftests/bpf: Validate libbpf's auto-sizing of LD/ST/STX instructions
Add selftests validating libbpf's auto-resizing of load/store instructions when used with CO-RE relocations. An explicit and manual approach with using bpf_core_read() is also demonstrated and tested. Separate BPF program is supposed to fail due to using signed integers of sizes that differ from kernel's sizes. To reliably simulate 32-bit BTF (i.e., the one with sizeof(long) == sizeof(void *) == 4), selftest generates its own custom BTF and passes it as a replacement for real kernel BTF. This allows to test 32/64-bitness mix on all architectures. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20201008001025.292064-5-andrii@kernel.org
This commit is contained in:
Andrii Nakryiko
Alexei Starovoitov
parent
2b7d88c2b5
commit
888d83b961
225
tools/testing/selftests/bpf/prog_tests/core_autosize.c
Normal file
225
tools/testing/selftests/bpf/prog_tests/core_autosize.c
Normal file
@ -0,0 +1,225 @@
|
|||||||
|
// 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(btf);
|
||||||
|
test_core_autosize__destroy(skel);
|
||||||
|
}
|
||||||
172
tools/testing/selftests/bpf/progs/test_core_autosize.c
Normal file
172
tools/testing/selftests/bpf/progs/test_core_autosize.c
Normal file
@ -0,0 +1,172 @@
|
|||||||
|
// SPDX-License-Identifier: GPL-2.0
|
||||||
|
/* Copyright (c) 2020 Facebook */
|
||||||
|
|
||||||
|
#include <linux/bpf.h>
|
||||||
|
#include <stdint.h>
|
||||||
|
#include <bpf/bpf_helpers.h>
|
||||||
|
#include <bpf/bpf_core_read.h>
|
||||||
|
|
||||||
|
char _license[] SEC("license") = "GPL";
|
||||||
|
|
||||||
|
/* fields of exactly the same size */
|
||||||
|
struct test_struct___samesize {
|
||||||
|
void *ptr;
|
||||||
|
unsigned long long val1;
|
||||||
|
unsigned int val2;
|
||||||
|
unsigned short val3;
|
||||||
|
unsigned char val4;
|
||||||
|
} __attribute((preserve_access_index));
|
||||||
|
|
||||||
|
/* unsigned fields that have to be downsized by libbpf */
|
||||||
|
struct test_struct___downsize {
|
||||||
|
void *ptr;
|
||||||
|
unsigned long val1;
|
||||||
|
unsigned long val2;
|
||||||
|
unsigned long val3;
|
||||||
|
unsigned long val4;
|
||||||
|
/* total sz: 40 */
|
||||||
|
} __attribute__((preserve_access_index));
|
||||||
|
|
||||||
|
/* fields with signed integers of wrong size, should be rejected */
|
||||||
|
struct test_struct___signed {
|
||||||
|
void *ptr;
|
||||||
|
long val1;
|
||||||
|
long val2;
|
||||||
|
long val3;
|
||||||
|
long val4;
|
||||||
|
} __attribute((preserve_access_index));
|
||||||
|
|
||||||
|
/* real layout and sizes according to test's (32-bit) BTF */
|
||||||
|
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;
|
||||||
|
/* total sz: 20 */
|
||||||
|
};
|
||||||
|
|
||||||
|
struct test_struct___real input = {
|
||||||
|
.ptr = 0x01020304,
|
||||||
|
.val1 = 0x1020304050607080,
|
||||||
|
.val2 = 0x0a0b0c0d,
|
||||||
|
.val3 = 0xfeed,
|
||||||
|
.val4 = 0xb9,
|
||||||
|
._pad = 0xff, /* make sure no accidental zeros are present */
|
||||||
|
};
|
||||||
|
|
||||||
|
unsigned long long ptr_samesized = 0;
|
||||||
|
unsigned long long val1_samesized = 0;
|
||||||
|
unsigned long long val2_samesized = 0;
|
||||||
|
unsigned long long val3_samesized = 0;
|
||||||
|
unsigned long long val4_samesized = 0;
|
||||||
|
struct test_struct___real output_samesized = {};
|
||||||
|
|
||||||
|
unsigned long long ptr_downsized = 0;
|
||||||
|
unsigned long long val1_downsized = 0;
|
||||||
|
unsigned long long val2_downsized = 0;
|
||||||
|
unsigned long long val3_downsized = 0;
|
||||||
|
unsigned long long val4_downsized = 0;
|
||||||
|
struct test_struct___real output_downsized = {};
|
||||||
|
|
||||||
|
unsigned long long ptr_probed = 0;
|
||||||
|
unsigned long long val1_probed = 0;
|
||||||
|
unsigned long long val2_probed = 0;
|
||||||
|
unsigned long long val3_probed = 0;
|
||||||
|
unsigned long long val4_probed = 0;
|
||||||
|
|
||||||
|
unsigned long long ptr_signed = 0;
|
||||||
|
unsigned long long val1_signed = 0;
|
||||||
|
unsigned long long val2_signed = 0;
|
||||||
|
unsigned long long val3_signed = 0;
|
||||||
|
unsigned long long val4_signed = 0;
|
||||||
|
struct test_struct___real output_signed = {};
|
||||||
|
|
||||||
|
SEC("raw_tp/sys_exit")
|
||||||
|
int handle_samesize(void *ctx)
|
||||||
|
{
|
||||||
|
struct test_struct___samesize *in = (void *)&input;
|
||||||
|
struct test_struct___samesize *out = (void *)&output_samesized;
|
||||||
|
|
||||||
|
ptr_samesized = (unsigned long long)in->ptr;
|
||||||
|
val1_samesized = in->val1;
|
||||||
|
val2_samesized = in->val2;
|
||||||
|
val3_samesized = in->val3;
|
||||||
|
val4_samesized = in->val4;
|
||||||
|
|
||||||
|
out->ptr = in->ptr;
|
||||||
|
out->val1 = in->val1;
|
||||||
|
out->val2 = in->val2;
|
||||||
|
out->val3 = in->val3;
|
||||||
|
out->val4 = in->val4;
|
||||||
|
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
SEC("raw_tp/sys_exit")
|
||||||
|
int handle_downsize(void *ctx)
|
||||||
|
{
|
||||||
|
struct test_struct___downsize *in = (void *)&input;
|
||||||
|
struct test_struct___downsize *out = (void *)&output_downsized;
|
||||||
|
|
||||||
|
ptr_downsized = (unsigned long long)in->ptr;
|
||||||
|
val1_downsized = in->val1;
|
||||||
|
val2_downsized = in->val2;
|
||||||
|
val3_downsized = in->val3;
|
||||||
|
val4_downsized = in->val4;
|
||||||
|
|
||||||
|
out->ptr = in->ptr;
|
||||||
|
out->val1 = in->val1;
|
||||||
|
out->val2 = in->val2;
|
||||||
|
out->val3 = in->val3;
|
||||||
|
out->val4 = in->val4;
|
||||||
|
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
SEC("raw_tp/sys_enter")
|
||||||
|
int handle_probed(void *ctx)
|
||||||
|
{
|
||||||
|
struct test_struct___downsize *in = (void *)&input;
|
||||||
|
__u64 tmp;
|
||||||
|
|
||||||
|
tmp = 0;
|
||||||
|
bpf_core_read(&tmp, bpf_core_field_size(in->ptr), &in->ptr);
|
||||||
|
ptr_probed = tmp;
|
||||||
|
|
||||||
|
tmp = 0;
|
||||||
|
bpf_core_read(&tmp, bpf_core_field_size(in->val1), &in->val1);
|
||||||
|
val1_probed = tmp;
|
||||||
|
|
||||||
|
tmp = 0;
|
||||||
|
bpf_core_read(&tmp, bpf_core_field_size(in->val2), &in->val2);
|
||||||
|
val2_probed = tmp;
|
||||||
|
|
||||||
|
tmp = 0;
|
||||||
|
bpf_core_read(&tmp, bpf_core_field_size(in->val3), &in->val3);
|
||||||
|
val3_probed = tmp;
|
||||||
|
|
||||||
|
tmp = 0;
|
||||||
|
bpf_core_read(&tmp, bpf_core_field_size(in->val4), &in->val4);
|
||||||
|
val4_probed = tmp;
|
||||||
|
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
SEC("raw_tp/sys_enter")
|
||||||
|
int handle_signed(void *ctx)
|
||||||
|
{
|
||||||
|
struct test_struct___signed *in = (void *)&input;
|
||||||
|
struct test_struct___signed *out = (void *)&output_signed;
|
||||||
|
|
||||||
|
val2_signed = in->val2;
|
||||||
|
val3_signed = in->val3;
|
||||||
|
val4_signed = in->val4;
|
||||||
|
|
||||||
|
out->val2= in->val2;
|
||||||
|
out->val3= in->val3;
|
||||||
|
out->val4= in->val4;
|
||||||
|
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
Loading…
Reference in New Issue
Block a user