Commit 9553de70 authored by Eduard Zingerman's avatar Eduard Zingerman Committed by Alexei Starovoitov
Browse files

selftests/bpf: verifier/div_overflow.c converted to inline assembly 



Test verifier/div_overflow.c automatically converted to use inline assembly.

Signed-off-by: default avatarEduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-20-eddyz87@gmail.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 01a09255

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

+2 −0
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ 
#include "verifier_ctx_sk_msg.skel.h"

#include "verifier_direct_stack_access_wraparound.skel.h"

#include "verifier_div0.skel.h"

#include "verifier_div_overflow.skel.h"



__maybe_unused

static void run_tests_aux(const char *skel_name, skel_elf_bytes_fn elf_bytes_factory)
@@ -54,3 +55,4 @@ void test_verifier_const_or(void) { RUN(verifier_const_or); } 
void test_verifier_ctx_sk_msg(void)           { RUN(verifier_ctx_sk_msg); }

void test_verifier_direct_stack_access_wraparound(void) { RUN(verifier_direct_stack_access_wraparound); }

void test_verifier_div0(void)                 { RUN(verifier_div0); }

void test_verifier_div_overflow(void)         { RUN(verifier_div_overflow); }

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

0 → 100644
+144 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/* Converted from tools/testing/selftests/bpf/verifier/div_overflow.c */



#include <linux/bpf.h>

#include <bpf/bpf_helpers.h>

#include <limits.h>

#include "bpf_misc.h"



/* Just make sure that JITs used udiv/umod as otherwise we get

 * an exception from INT_MIN/-1 overflow similarly as with div

 * by zero.

 */



SEC("tc")

__description("DIV32 overflow, check 1")

__success __retval(0)

__naked void div32_overflow_check_1(void)

{

	asm volatile ("					\

	w1 = -1;					\

	w0 = %[int_min];				\

	w0 /= w1;					\

	exit;						\

"	:

	: __imm_const(int_min, INT_MIN)

	: __clobber_all);

}



SEC("tc")

__description("DIV32 overflow, check 2")

__success __retval(0)

__naked void div32_overflow_check_2(void)

{

	asm volatile ("					\

	w0 = %[int_min];				\

	w0 /= -1;					\

	exit;						\

"	:

	: __imm_const(int_min, INT_MIN)

	: __clobber_all);

}



SEC("tc")

__description("DIV64 overflow, check 1")

__success __retval(0)

__naked void div64_overflow_check_1(void)

{

	asm volatile ("					\

	r1 = -1;					\

	r2 = %[llong_min] ll;				\

	r2 /= r1;					\

	w0 = 0;						\

	if r0 == r2 goto l0_%=;				\

	w0 = 1;						\

l0_%=:	exit;						\

"	:

	: __imm_const(llong_min, LLONG_MIN)

	: __clobber_all);

}



SEC("tc")

__description("DIV64 overflow, check 2")

__success __retval(0)

__naked void div64_overflow_check_2(void)

{

	asm volatile ("					\

	r1 = %[llong_min] ll;				\

	r1 /= -1;					\

	w0 = 0;						\

	if r0 == r1 goto l0_%=;				\

	w0 = 1;						\

l0_%=:	exit;						\

"	:

	: __imm_const(llong_min, LLONG_MIN)

	: __clobber_all);

}



SEC("tc")

__description("MOD32 overflow, check 1")

__success __retval(INT_MIN)

__naked void mod32_overflow_check_1(void)

{

	asm volatile ("					\

	w1 = -1;					\

	w0 = %[int_min];				\

	w0 %%= w1;					\

	exit;						\

"	:

	: __imm_const(int_min, INT_MIN)

	: __clobber_all);

}



SEC("tc")

__description("MOD32 overflow, check 2")

__success __retval(INT_MIN)

__naked void mod32_overflow_check_2(void)

{

	asm volatile ("					\

	w0 = %[int_min];				\

	w0 %%= -1;					\

	exit;						\

"	:

	: __imm_const(int_min, INT_MIN)

	: __clobber_all);

}



SEC("tc")

__description("MOD64 overflow, check 1")

__success __retval(1)

__naked void mod64_overflow_check_1(void)

{

	asm volatile ("					\

	r1 = -1;					\

	r2 = %[llong_min] ll;				\

	r3 = r2;					\

	r2 %%= r1;					\

	w0 = 0;						\

	if r3 != r2 goto l0_%=;				\

	w0 = 1;						\

l0_%=:	exit;						\

"	:

	: __imm_const(llong_min, LLONG_MIN)

	: __clobber_all);

}



SEC("tc")

__description("MOD64 overflow, check 2")

__success __retval(1)

__naked void mod64_overflow_check_2(void)

{

	asm volatile ("					\

	r2 = %[llong_min] ll;				\

	r3 = r2;					\

	r2 %%= -1;					\

	w0 = 0;						\

	if r3 != r2 goto l0_%=;				\

	w0 = 1;						\

l0_%=:	exit;						\

"	:

	: __imm_const(llong_min, LLONG_MIN)

	: __clobber_all);

}



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

tools/testing/selftests/bpf/verifier/div_overflow.c

deleted100644 → 0
+0 −110
Original line number Diff line number Diff line 
/* Just make sure that JITs used udiv/umod as otherwise we get

 * an exception from INT_MIN/-1 overflow similarly as with div

 * by zero.

 */

{

	"DIV32 overflow, check 1",

	.insns = {

	BPF_MOV32_IMM(BPF_REG_1, -1),

	BPF_MOV32_IMM(BPF_REG_0, INT_MIN),

	BPF_ALU32_REG(BPF_DIV, BPF_REG_0, BPF_REG_1),

	BPF_EXIT_INSN(),

	},

	.prog_type = BPF_PROG_TYPE_SCHED_CLS,

	.result = ACCEPT,

	.retval = 0,

},

{

	"DIV32 overflow, check 2",

	.insns = {

	BPF_MOV32_IMM(BPF_REG_0, INT_MIN),

	BPF_ALU32_IMM(BPF_DIV, BPF_REG_0, -1),

	BPF_EXIT_INSN(),

	},

	.prog_type = BPF_PROG_TYPE_SCHED_CLS,

	.result = ACCEPT,

	.retval = 0,

},

{

	"DIV64 overflow, check 1",

	.insns = {

	BPF_MOV64_IMM(BPF_REG_1, -1),

	BPF_LD_IMM64(BPF_REG_2, LLONG_MIN),

	BPF_ALU64_REG(BPF_DIV, BPF_REG_2, BPF_REG_1),

	BPF_MOV32_IMM(BPF_REG_0, 0),

	BPF_JMP_REG(BPF_JEQ, BPF_REG_0, BPF_REG_2, 1),

	BPF_MOV32_IMM(BPF_REG_0, 1),

	BPF_EXIT_INSN(),

	},

	.prog_type = BPF_PROG_TYPE_SCHED_CLS,

	.result = ACCEPT,

	.retval = 0,

},

{

	"DIV64 overflow, check 2",

	.insns = {

	BPF_LD_IMM64(BPF_REG_1, LLONG_MIN),

	BPF_ALU64_IMM(BPF_DIV, BPF_REG_1, -1),

	BPF_MOV32_IMM(BPF_REG_0, 0),

	BPF_JMP_REG(BPF_JEQ, BPF_REG_0, BPF_REG_1, 1),

	BPF_MOV32_IMM(BPF_REG_0, 1),

	BPF_EXIT_INSN(),

	},

	.prog_type = BPF_PROG_TYPE_SCHED_CLS,

	.result = ACCEPT,

	.retval = 0,

},

{

	"MOD32 overflow, check 1",

	.insns = {

	BPF_MOV32_IMM(BPF_REG_1, -1),

	BPF_MOV32_IMM(BPF_REG_0, INT_MIN),

	BPF_ALU32_REG(BPF_MOD, BPF_REG_0, BPF_REG_1),

	BPF_EXIT_INSN(),

	},

	.prog_type = BPF_PROG_TYPE_SCHED_CLS,

	.result = ACCEPT,

	.retval = INT_MIN,

},

{

	"MOD32 overflow, check 2",

	.insns = {

	BPF_MOV32_IMM(BPF_REG_0, INT_MIN),

	BPF_ALU32_IMM(BPF_MOD, BPF_REG_0, -1),

	BPF_EXIT_INSN(),

	},

	.prog_type = BPF_PROG_TYPE_SCHED_CLS,

	.result = ACCEPT,

	.retval = INT_MIN,

},

{

	"MOD64 overflow, check 1",

	.insns = {

	BPF_MOV64_IMM(BPF_REG_1, -1),

	BPF_LD_IMM64(BPF_REG_2, LLONG_MIN),

	BPF_MOV64_REG(BPF_REG_3, BPF_REG_2),

	BPF_ALU64_REG(BPF_MOD, BPF_REG_2, BPF_REG_1),

	BPF_MOV32_IMM(BPF_REG_0, 0),

	BPF_JMP_REG(BPF_JNE, BPF_REG_3, BPF_REG_2, 1),

	BPF_MOV32_IMM(BPF_REG_0, 1),

	BPF_EXIT_INSN(),

	},

	.prog_type = BPF_PROG_TYPE_SCHED_CLS,

	.result = ACCEPT,

	.retval = 1,

},

{

	"MOD64 overflow, check 2",

	.insns = {

	BPF_LD_IMM64(BPF_REG_2, LLONG_MIN),

	BPF_MOV64_REG(BPF_REG_3, BPF_REG_2),

	BPF_ALU64_IMM(BPF_MOD, BPF_REG_2, -1),

	BPF_MOV32_IMM(BPF_REG_0, 0),

	BPF_JMP_REG(BPF_JNE, BPF_REG_3, BPF_REG_2, 1),

	BPF_MOV32_IMM(BPF_REG_0, 1),

	BPF_EXIT_INSN(),

	},

	.prog_type = BPF_PROG_TYPE_SCHED_CLS,

	.result = ACCEPT,

	.retval = 1,

},