Commit 29e1c668 authored by Andrii Nakryiko's avatar Andrii Nakryiko Committed by Alexei Starovoitov
Browse files

selftests/bpf: add CO-RE relocs misc tests 



Add tests validating few edge-cases of capturing offset relocations.

Signed-off-by: default avatarAndrii Nakryiko <andriin@fb.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent c1f5e7dd

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

+19 −0
Original line number Diff line number Diff line
@@ -260,6 +260,25 @@ static struct core_reloc_test_case test_cases[] = { 
	INTS_ERR_CASE(ints___err_wrong_sz_16),

	INTS_ERR_CASE(ints___err_wrong_sz_32),

	INTS_ERR_CASE(ints___err_wrong_sz_64),

	

	/* validate edge cases of capturing relocations */

	{

		.case_name = "misc",

		.bpf_obj_file = "test_core_reloc_misc.o",

		.btf_src_file = "btf__core_reloc_misc.o",

		.input = (const char *)&(struct core_reloc_misc_extensible[]){

			{ .a = 1 },

			{ .a = 2 }, /* not read */

			{ .a = 3 },

		},

		.input_len = 4 * sizeof(int),

		.output = STRUCT_TO_CHAR_PTR(core_reloc_misc_output) {

			.a = 1,

			.b = 1,

			.c = 0, /* BUG in clang, should be 3 */

		},

		.output_len = sizeof(struct core_reloc_misc_output),

	},

};



struct data {

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

0 → 100644
+5 −0
Original line number Diff line number Diff line 
#include "core_reloc_types.h"



void f1(struct core_reloc_misc___a x) {}

void f2(struct core_reloc_misc___b x) {}

void f3(struct core_reloc_misc_extensible x) {}

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

+25 −0
Original line number Diff line number Diff line
@@ -640,3 +640,28 @@ struct core_reloc_ints___err_wrong_sz_64 { 
	uint32_t	u64_field; /* not 64-bit anymore */

	int32_t		s64_field; /* not 64-bit anymore */

};



/*

 * MISC

 */

struct core_reloc_misc_output {

	int a, b, c;

};



struct core_reloc_misc___a {

	int a1;

	int a2;

};



struct core_reloc_misc___b {

	int b1;

	int b2;

};



/* this one extends core_reloc_misc_extensible struct from BPF prog */

struct core_reloc_misc_extensible {

	int a;

	int b;

	int c;

	int d;

};

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

0 → 100644
+57 −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"



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



static volatile struct data {

	char in[256];

	char out[256];

} data;



struct core_reloc_misc_output {

	int a, b, c;

};



struct core_reloc_misc___a {

	int a1;

	int a2;

};



struct core_reloc_misc___b {

	int b1;

	int b2;

};



/* fixed two first members, can be extended with new fields */

struct core_reloc_misc_extensible {

	int a;

	int b;

};



SEC("raw_tracepoint/sys_enter")

int test_core_misc(void *ctx)

{

	struct core_reloc_misc___a *in_a = (void *)&data.in;

	struct core_reloc_misc___b *in_b = (void *)&data.in;

	struct core_reloc_misc_extensible *in_ext = (void *)&data.in;

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



	/* record two different relocations with the same accessor string */

	if (BPF_CORE_READ(&out->a, &in_a->a1) ||	/* accessor: 0:0 */

	    BPF_CORE_READ(&out->b, &in_b->b1))		/* accessor: 0:0 */

		return 1;



	/* Validate relocations capture array-only accesses for structs with

	 * fixed header, but with potentially extendable tail. This will read

	 * first 4 bytes of 2nd element of in_ext array of potentially

	 * variably sized struct core_reloc_misc_extensible. */ 

	if (BPF_CORE_READ(&out->c, &in_ext[2]))		/* accessor: 2 */

		return 1;



	return 0;

}