From: Andrii Nakryiko andriin@fb.com
[ Upstream commit 5705d705832f74395c5465ce93192688f543006a ]
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 --- .../selftests/bpf/prog_tests/core_reloc.c | 20 +++--- .../selftests/bpf/progs/core_reloc_types.h | 69 ++++++++++--------- 2 files changed, 47 insertions(+), 42 deletions(-)
diff --git a/tools/testing/selftests/bpf/prog_tests/core_reloc.c b/tools/testing/selftests/bpf/prog_tests/core_reloc.c index 084ed26a7d78c..a54eafc5e4b31 100644 --- a/tools/testing/selftests/bpf/prog_tests/core_reloc.c +++ b/tools/testing/selftests/bpf/prog_tests/core_reloc.c @@ -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) { \ @@ -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),
diff --git a/tools/testing/selftests/bpf/progs/core_reloc_types.h b/tools/testing/selftests/bpf/progs/core_reloc_types.h index 6d598cfbdb3e2..f9da9f62c4b34 100644 --- a/tools/testing/selftests/bpf/progs/core_reloc_types.h +++ b/tools/testing/selftests/bpf/progs/core_reloc_types.h @@ -1,5 +1,10 @@ #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; };
@@ -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 {