Commit 0b163565 authored by Andrii Nakryiko's avatar Andrii Nakryiko Committed by Daniel Borkmann
Browse files

selftests/bpf: Add field size relocation tests 



Add test verifying correctness and logic of field size relocation support in
libbpf.

Signed-off-by: default avatarAndrii Nakryiko <andriin@fb.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191101222810.1246166-6-andriin@fb.com
parent 8b1cb1c9

tools/testing/selftests/bpf/prog_tests/core_reloc.c

+34 −5
Original line number Diff line number Diff line
@@ -174,15 +174,11 @@ 
	.fails = true,							\

}



#define EXISTENCE_DATA(struct_name) STRUCT_TO_CHAR_PTR(struct_name) {	\

	.a = 42,							\

}



#define EXISTENCE_CASE_COMMON(name)					\

	.case_name = #name,						\

	.bpf_obj_file = "test_core_reloc_existence.o",			\

	.btf_src_file = "btf__core_reloc_" #name ".o",			\

	.relaxed_core_relocs = true					\

	.relaxed_core_relocs = true



#define EXISTENCE_ERR_CASE(name) {					\

	EXISTENCE_CASE_COMMON(name),					\
@@ -225,6 +221,35 @@ 
	.fails = true,							\

}



#define SIZE_CASE_COMMON(name)						\

	.case_name = #name,						\

	.bpf_obj_file = "test_core_reloc_size.o",			\

	.btf_src_file = "btf__core_reloc_" #name ".o",			\

	.relaxed_core_relocs = true



#define SIZE_OUTPUT_DATA(type)						\

	STRUCT_TO_CHAR_PTR(core_reloc_size_output) {			\

		.int_sz = sizeof(((type *)0)->int_field),		\

		.struct_sz = sizeof(((type *)0)->struct_field),		\

		.union_sz = sizeof(((type *)0)->union_field),		\

		.arr_sz = sizeof(((type *)0)->arr_field),		\

		.arr_elem_sz = sizeof(((type *)0)->arr_field[0]),	\

		.ptr_sz = sizeof(((type *)0)->ptr_field),		\

		.enum_sz = sizeof(((type *)0)->enum_field),	\

	}



#define SIZE_CASE(name) {						\

	SIZE_CASE_COMMON(name),						\

	.input_len = 0,							\

	.output = SIZE_OUTPUT_DATA(struct core_reloc_##name),		\

	.output_len = sizeof(struct core_reloc_size_output),		\

}



#define SIZE_ERR_CASE(name) {						\

	SIZE_CASE_COMMON(name),						\

	.fails = true,							\

}



struct core_reloc_test_case {

	const char *case_name;

	const char *bpf_obj_file;
@@ -423,6 +448,10 @@ static struct core_reloc_test_case test_cases[] = { 
		.ub2 = 0x0812345678FEDCBA,

	}),

	BITFIELDS_ERR_CASE(bitfields___err_too_big_bitfield),



	/* size relocation checks */

	SIZE_CASE(size),

	SIZE_CASE(size___diff_sz),

};



struct data {

tools/testing/selftests/bpf/progs/btf__core_reloc_size.c

0 → 100644
+3 −0
Original line number Diff line number Diff line 
#include "core_reloc_types.h"



void f(struct core_reloc_size x) {}

tools/testing/selftests/bpf/progs/btf__core_reloc_size___diff_sz.c

0 → 100644
+3 −0
Original line number Diff line number Diff line 
#include "core_reloc_types.h"



void f(struct core_reloc_size___diff_sz x) {}

tools/testing/selftests/bpf/progs/core_reloc_types.h

+31 −0
Original line number Diff line number Diff line
@@ -734,3 +734,34 @@ struct core_reloc_bitfields___err_too_big_bitfield { 
	uint32_t	u32;

	uint32_t	s32;

} __attribute__((packed)) ;



/*

 * SIZE

 */

struct core_reloc_size_output {

	int int_sz;

	int struct_sz;

	int union_sz;

	int arr_sz;

	int arr_elem_sz;

	int ptr_sz;

	int enum_sz;

};



struct core_reloc_size {

	int int_field;

	struct { int x; } struct_field;

	union { int x; } union_field;

	int arr_field[4];

	void *ptr_field;

	enum { VALUE = 123 } enum_field;

};



struct core_reloc_size___diff_sz {

	uint64_t int_field;

	struct { int x; int y; int z; } struct_field;

	union { int x; char bla[123]; } union_field;

	char arr_field[10];

	void *ptr_field;

	enum { OTHER_VALUE = 0xFFFFFFFFFFFFFFFF } enum_field;

};

tools/testing/selftests/bpf/progs/test_core_reloc_size.c

0 → 100644
+51 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

// Copyright (c) 2019 Facebook



#include <linux/bpf.h>

#include <stdint.h>

#include "bpf_helpers.h"

#include "bpf_core_read.h"



char _license[] SEC("license") = "GPL";



static volatile struct data {

	char in[256];

	char out[256];

} data;



struct core_reloc_size_output {

	int int_sz;

	int struct_sz;

	int union_sz;

	int arr_sz;

	int arr_elem_sz;

	int ptr_sz;

	int enum_sz;

};



struct core_reloc_size {

	int int_field;

	struct { int x; } struct_field;

	union { int x; } union_field;

	int arr_field[4];

	void *ptr_field;

	enum { VALUE = 123 } enum_field;

};



SEC("raw_tracepoint/sys_enter")

int test_core_size(void *ctx)

{

	struct core_reloc_size *in = (void *)&data.in;

	struct core_reloc_size_output *out = (void *)&data.out;



	out->int_sz = bpf_core_field_size(in->int_field);

	out->struct_sz = bpf_core_field_size(in->struct_field);

	out->union_sz = bpf_core_field_size(in->union_field);

	out->arr_sz = bpf_core_field_size(in->arr_field);

	out->arr_elem_sz = bpf_core_field_size(in->arr_field[0]);

	out->ptr_sz = bpf_core_field_size(in->ptr_field);

	out->enum_sz = bpf_core_field_size(in->enum_field);



	return 0;

}