Commit 5705d705 authored by Andrii Nakryiko's avatar Andrii Nakryiko Committed by Alexei Starovoitov
Browse files

selftests/bpf: Correct various core_reloc 64-bit assumptions 



Ensure that types are memory layout- and field alignment-compatible regardless
of 32/64-bitness mix of libbpf and BPF architecture.

Signed-off-by: default avatarAndrii Nakryiko <andriin@fb.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200813204945.1020225-8-andriin@fb.com
parent 4c01925f

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

+10 −10
Original line number Diff line number Diff line
@@ -237,7 +237,7 @@ 
		.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),		\

		.ptr_sz = 8, /* always 8-byte pointer for BPF */	\

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

	}
@@ -432,20 +432,20 @@ static struct core_reloc_test_case test_cases[] = { 
		.sb4 = -1,

		.sb20 = -0x17654321,

		.u32 = 0xBEEF,

		.s32 = -0x3FEDCBA987654321,

		.s32 = -0x3FEDCBA987654321LL,

	}),

	BITFIELDS_CASE(bitfields___bitfield_vs_int, {

		.ub1 = 0xFEDCBA9876543210,

		.ub1 = 0xFEDCBA9876543210LL,

		.ub2 = 0xA6,

		.ub7 = -0x7EDCBA987654321,

		.sb4 = -0x6123456789ABCDE,

		.sb20 = 0xD00D,

		.ub7 = -0x7EDCBA987654321LL,

		.sb4 = -0x6123456789ABCDELL,

		.sb20 = 0xD00DLL,

		.u32 = -0x76543,

		.s32 = 0x0ADEADBEEFBADB0B,

		.s32 = 0x0ADEADBEEFBADB0BLL,

	}),

	BITFIELDS_CASE(bitfields___just_big_enough, {

		.ub1 = 0xF,

		.ub2 = 0x0812345678FEDCBA,

		.ub1 = 0xFLL,

		.ub2 = 0x0812345678FEDCBALL,

	}),

	BITFIELDS_ERR_CASE(bitfields___err_too_big_bitfield),

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

+37 −32
Original line number Diff line number Diff line 
#include <stdint.h>

#include <stdbool.h>



void preserce_ptr_sz_fn(long x) {}



#define __bpf_aligned __attribute__((aligned(8)))



/*

 * KERNEL

 */
@@ -444,51 +449,51 @@ struct core_reloc_primitives { 
	char a;

	int b;

	enum core_reloc_primitives_enum c;

	void *d;

	int (*f)(const char *);

	void *d __bpf_aligned;

	int (*f)(const char *) __bpf_aligned;

};



struct core_reloc_primitives___diff_enum_def {

	char a;

	int b;

	void *d;

	int (*f)(const char *);

	void *d __bpf_aligned;

	int (*f)(const char *) __bpf_aligned;

	enum {

		X = 100,

		Y = 200,

	} c; /* inline enum def with differing set of values */

	} c __bpf_aligned; /* inline enum def with differing set of values */

};



struct core_reloc_primitives___diff_func_proto {

	void (*f)(int); /* incompatible function prototype */

	void *d;

	enum core_reloc_primitives_enum c;

	void (*f)(int) __bpf_aligned; /* incompatible function prototype */

	void *d __bpf_aligned;

	enum core_reloc_primitives_enum c __bpf_aligned;

	int b;

	char a;

};



struct core_reloc_primitives___diff_ptr_type {

	const char * const d; /* different pointee type + modifiers */

	char a;

	const char * const d __bpf_aligned; /* different pointee type + modifiers */

	char a __bpf_aligned;

	int b;

	enum core_reloc_primitives_enum c;

	int (*f)(const char *);

	int (*f)(const char *) __bpf_aligned;

};



struct core_reloc_primitives___err_non_enum {

	char a[1];

	int b;

	int c; /* int instead of enum */

	void *d;

	int (*f)(const char *);

	void *d __bpf_aligned;

	int (*f)(const char *) __bpf_aligned;

};



struct core_reloc_primitives___err_non_int {

	char a[1];

	int *b; /* ptr instead of int */

	enum core_reloc_primitives_enum c;

	void *d;

	int (*f)(const char *);

	int *b __bpf_aligned; /* ptr instead of int */

	enum core_reloc_primitives_enum c __bpf_aligned;

	void *d __bpf_aligned;

	int (*f)(const char *) __bpf_aligned;

};



struct core_reloc_primitives___err_non_ptr {
@@ -496,7 +501,7 @@ struct core_reloc_primitives___err_non_ptr { 
	int b;

	enum core_reloc_primitives_enum c;

	int d; /* int instead of ptr */

	int (*f)(const char *);

	int (*f)(const char *) __bpf_aligned;

};



/*
@@ -507,7 +512,7 @@ struct core_reloc_mods_output { 
};



typedef const int int_t;

typedef const char *char_ptr_t;

typedef const char *char_ptr_t __bpf_aligned;

typedef const int arr_t[7];



struct core_reloc_mods_substruct {
@@ -523,9 +528,9 @@ typedef struct { 
struct core_reloc_mods {

	int a;

	int_t b;

	char *c;

	char *c __bpf_aligned;

	char_ptr_t d;

	int e[3];

	int e[3] __bpf_aligned;

	arr_t f;

	struct core_reloc_mods_substruct g;

	core_reloc_mods_substruct_t h;
@@ -535,9 +540,9 @@ struct core_reloc_mods { 
struct core_reloc_mods___mod_swap {

	int b;

	int_t a;

	char *d;

	char *d __bpf_aligned;

	char_ptr_t c;

	int f[3];

	int f[3] __bpf_aligned;

	arr_t e;

	struct {

		int y;
@@ -555,7 +560,7 @@ typedef arr1_t arr2_t; 
typedef arr2_t arr3_t;

typedef arr3_t arr4_t;



typedef const char * const volatile fancy_char_ptr_t;

typedef const char * const volatile fancy_char_ptr_t __bpf_aligned;



typedef core_reloc_mods_substruct_t core_reloc_mods_substruct_tt;
@@ -567,7 +572,7 @@ struct core_reloc_mods___typedefs { 
	arr4_t e;

	fancy_char_ptr_t d;

	fancy_char_ptr_t c;

	int3_t b;

	int3_t b __bpf_aligned;

	int3_t a;

};
@@ -740,18 +745,18 @@ struct core_reloc_bitfields___bit_sz_change { 
	int32_t		sb20: 30;	/* 20 -> 30 */

	/* non-bitfields */

	uint16_t	u32;			/* 32 -> 16 */

	int64_t		s32;		/* 32 -> 64 */

	int64_t		s32 __bpf_aligned;	/* 32 -> 64 */

};



/* turn bitfield into non-bitfield and vice versa */

struct core_reloc_bitfields___bitfield_vs_int {

	uint64_t	ub1;		/*  3 -> 64 non-bitfield */

	uint8_t		ub2;		/* 20 ->  8 non-bitfield */

	int64_t		ub7;		/*  7 -> 64 non-bitfield signed */

	int64_t		sb4;		/*  4 -> 64 non-bitfield signed */

	uint64_t	sb20;		/* 20 -> 16 non-bitfield unsigned */

	int64_t		ub7 __bpf_aligned;	/*  7 -> 64 non-bitfield signed */

	int64_t		sb4 __bpf_aligned;	/*  4 -> 64 non-bitfield signed */

	uint64_t	sb20 __bpf_aligned;	/* 20 -> 16 non-bitfield unsigned */

	int32_t		u32: 20;		/* 32 non-bitfield -> 20 bitfield */

	uint64_t	s32: 60;	/* 32 non-bitfield -> 60 bitfield */

	uint64_t	s32: 60 __bpf_aligned;	/* 32 non-bitfield -> 60 bitfield */

};



struct core_reloc_bitfields___just_big_enough {