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selftests/bpf: Correct various core_reloc 64-bit assumptions
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[ Upstream commit 5705d70 ]

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

Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200813204945.1020225-8-andriin@fb.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
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@anakryiko @gregkh
anakryiko authored and gregkh committed Sep 3, 2020
1 parent 751799b commit da9c02c
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Showing 2 changed files with 47 additions and 42 deletions.
20 changes: 10 additions & 10 deletions tools/testing/selftests/bpf/prog_tests/core_reloc.c
View file
Expand Up @@ -237,8 +237,8 @@
.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), \
.ptr_sz = 8, /* always 8-byte pointer for BPF */ \
.enum_sz = sizeof(((type *)0)->enum_field), \
}

#define SIZE_CASE(name) { \
Expand Down Expand Up @@ -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),

Expand Down
69 changes: 37 additions & 32 deletions tools/testing/selftests/bpf/progs/core_reloc_types.h
View file
@@ -1,5 +1,10 @@
#include <stdint.h>
#include <stdbool.h>

void preserce_ptr_sz_fn(long x) {}

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

/*
* KERNEL
*/
Expand Down Expand Up @@ -444,59 +449,59 @@ 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 {
char a[1];
int b;
enum core_reloc_primitives_enum c;
int d; /* int instead of ptr */
int (*f)(const char *);
int (*f)(const char *) __bpf_aligned;
};

/*
Expand All @@ -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 {
Expand All @@ -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;
Expand All @@ -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;
Expand All @@ -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;

Expand All @@ -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;
};

Expand Down Expand Up @@ -739,19 +744,19 @@ struct core_reloc_bitfields___bit_sz_change {
int8_t sb4: 1; /* 4 -> 1 */
int32_t sb20: 30; /* 20 -> 30 */
/* non-bitfields */
uint16_t u32; /* 32 -> 16 */
int64_t s32; /* 32 -> 64 */
uint16_t u32; /* 32 -> 16 */
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 */
int32_t u32: 20; /* 32 non-bitfield -> 20 bitfield */
uint64_t s32: 60; /* 32 non-bitfield -> 60 bitfield */
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 __bpf_aligned; /* 32 non-bitfield -> 60 bitfield */
};

struct core_reloc_bitfields___just_big_enough {
Expand Down

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