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bpf: add ld64 imm test cases
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Add test cases where we combine semi-random imm values, mainly for testing
JITs when they have different encoding options for 64 bit immediates in
order to reduce resulting image size.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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borkmann authored and Alexei Starovoitov committed May 15, 2018
1 parent 56ea6a8 commit a82d8cd
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Showing 2 changed files with 142 additions and 0 deletions.
80 changes: 80 additions & 0 deletions tools/testing/selftests/bpf/bpf_rand.h
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@@ -0,0 +1,80 @@
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __BPF_RAND__
#define __BPF_RAND__

#include <stdint.h>
#include <stdlib.h>
#include <time.h>

static inline uint64_t bpf_rand_mask(uint64_t mask)
{
return (((uint64_t)(uint32_t)rand()) |
((uint64_t)(uint32_t)rand() << 32)) & mask;
}

#define bpf_rand_ux(x, m) \
static inline uint64_t bpf_rand_u##x(int shift) \
{ \
return bpf_rand_mask((m)) << shift; \
}

bpf_rand_ux( 8, 0xffULL)
bpf_rand_ux(16, 0xffffULL)
bpf_rand_ux(24, 0xffffffULL)
bpf_rand_ux(32, 0xffffffffULL)
bpf_rand_ux(40, 0xffffffffffULL)
bpf_rand_ux(48, 0xffffffffffffULL)
bpf_rand_ux(56, 0xffffffffffffffULL)
bpf_rand_ux(64, 0xffffffffffffffffULL)

static inline void bpf_semi_rand_init(void)
{
srand(time(NULL));
}

static inline uint64_t bpf_semi_rand_get(void)
{
switch (rand() % 39) {
case 0: return 0x000000ff00000000ULL | bpf_rand_u8(0);
case 1: return 0xffffffff00000000ULL | bpf_rand_u16(0);
case 2: return 0x00000000ffff0000ULL | bpf_rand_u16(0);
case 3: return 0x8000000000000000ULL | bpf_rand_u32(0);
case 4: return 0x00000000f0000000ULL | bpf_rand_u32(0);
case 5: return 0x0000000100000000ULL | bpf_rand_u24(0);
case 6: return 0x800ff00000000000ULL | bpf_rand_u32(0);
case 7: return 0x7fffffff00000000ULL | bpf_rand_u32(0);
case 8: return 0xffffffffffffff00ULL ^ bpf_rand_u32(24);
case 9: return 0xffffffffffffff00ULL | bpf_rand_u8(0);
case 10: return 0x0000000010000000ULL | bpf_rand_u32(0);
case 11: return 0xf000000000000000ULL | bpf_rand_u8(0);
case 12: return 0x0000f00000000000ULL | bpf_rand_u8(8);
case 13: return 0x000000000f000000ULL | bpf_rand_u8(16);
case 14: return 0x0000000000000f00ULL | bpf_rand_u8(32);
case 15: return 0x00fff00000000f00ULL | bpf_rand_u8(48);
case 16: return 0x00007fffffffffffULL ^ bpf_rand_u32(1);
case 17: return 0xffff800000000000ULL | bpf_rand_u8(4);
case 18: return 0xffff800000000000ULL | bpf_rand_u8(20);
case 19: return (0xffffffc000000000ULL + 0x80000ULL) | bpf_rand_u32(0);
case 20: return (0xffffffc000000000ULL - 0x04000000ULL) | bpf_rand_u32(0);
case 21: return 0x0000000000000000ULL | bpf_rand_u8(55) | bpf_rand_u32(20);
case 22: return 0xffffffffffffffffULL ^ bpf_rand_u8(3) ^ bpf_rand_u32(40);
case 23: return 0x0000000000000000ULL | bpf_rand_u8(bpf_rand_u8(0) % 64);
case 24: return 0x0000000000000000ULL | bpf_rand_u16(bpf_rand_u8(0) % 64);
case 25: return 0xffffffffffffffffULL ^ bpf_rand_u8(bpf_rand_u8(0) % 64);
case 26: return 0xffffffffffffffffULL ^ bpf_rand_u40(bpf_rand_u8(0) % 64);
case 27: return 0x0000800000000000ULL;
case 28: return 0x8000000000000000ULL;
case 29: return 0x0000000000000000ULL;
case 30: return 0xffffffffffffffffULL;
case 31: return bpf_rand_u16(bpf_rand_u8(0) % 64);
case 32: return bpf_rand_u24(bpf_rand_u8(0) % 64);
case 33: return bpf_rand_u32(bpf_rand_u8(0) % 64);
case 34: return bpf_rand_u40(bpf_rand_u8(0) % 64);
case 35: return bpf_rand_u48(bpf_rand_u8(0) % 64);
case 36: return bpf_rand_u56(bpf_rand_u8(0) % 64);
case 37: return bpf_rand_u64(bpf_rand_u8(0) % 64);
default: return bpf_rand_u64(0);
}
}

#endif /* __BPF_RAND__ */
62 changes: 62 additions & 0 deletions tools/testing/selftests/bpf/test_verifier.c
View file
Expand Up @@ -41,6 +41,7 @@
# endif
#endif
#include "bpf_rlimit.h"
#include "bpf_rand.h"
#include "../../../include/linux/filter.h"

#ifndef ARRAY_SIZE
Expand Down Expand Up @@ -152,6 +153,30 @@ static void bpf_fill_jump_around_ld_abs(struct bpf_test *self)
insn[i] = BPF_EXIT_INSN();
}

static void bpf_fill_rand_ld_dw(struct bpf_test *self)
{
struct bpf_insn *insn = self->insns;
uint64_t res = 0;
int i = 0;

insn[i++] = BPF_MOV32_IMM(BPF_REG_0, 0);
while (i < self->retval) {
uint64_t val = bpf_semi_rand_get();
struct bpf_insn tmp[2] = { BPF_LD_IMM64(BPF_REG_1, val) };

res ^= val;
insn[i++] = tmp[0];
insn[i++] = tmp[1];
insn[i++] = BPF_ALU64_REG(BPF_XOR, BPF_REG_0, BPF_REG_1);
}
insn[i++] = BPF_MOV64_REG(BPF_REG_1, BPF_REG_0);
insn[i++] = BPF_ALU64_IMM(BPF_RSH, BPF_REG_1, 32);
insn[i++] = BPF_ALU64_REG(BPF_XOR, BPF_REG_0, BPF_REG_1);
insn[i] = BPF_EXIT_INSN();
res ^= (res >> 32);
self->retval = (uint32_t)res;
}

static struct bpf_test tests[] = {
{
"add+sub+mul",
Expand Down Expand Up @@ -11974,6 +11999,42 @@ static struct bpf_test tests[] = {
.result = ACCEPT,
.retval = 10,
},
{
"ld_dw: xor semi-random 64 bit imms, test 1",
.insns = { },
.data = { },
.fill_helper = bpf_fill_rand_ld_dw,
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.result = ACCEPT,
.retval = 4090,
},
{
"ld_dw: xor semi-random 64 bit imms, test 2",
.insns = { },
.data = { },
.fill_helper = bpf_fill_rand_ld_dw,
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.result = ACCEPT,
.retval = 2047,
},
{
"ld_dw: xor semi-random 64 bit imms, test 3",
.insns = { },
.data = { },
.fill_helper = bpf_fill_rand_ld_dw,
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.result = ACCEPT,
.retval = 511,
},
{
"ld_dw: xor semi-random 64 bit imms, test 4",
.insns = { },
.data = { },
.fill_helper = bpf_fill_rand_ld_dw,
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
.result = ACCEPT,
.retval = 5,
},
};

static int probe_filter_length(const struct bpf_insn *fp)
Expand Down Expand Up @@ -12346,5 +12407,6 @@ int main(int argc, char **argv)
return EXIT_FAILURE;
}

bpf_semi_rand_init();
return do_test(unpriv, from, to);
}

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