Commit 05e474ec authored by Eduard Zingerman's avatar Eduard Zingerman Committed by Alexei Starovoitov
Browse files

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



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

Signed-off-by: default avatarEduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-29-eddyz87@gmail.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent caf345cf

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

+2 −0
Original line number Diff line number Diff line
@@ -25,6 +25,7 @@ 
#include "verifier_ld_ind.skel.h"

#include "verifier_leak_ptr.skel.h"

#include "verifier_map_ptr.skel.h"

#include "verifier_map_ret_val.skel.h"



__maybe_unused

static void run_tests_aux(const char *skel_name, skel_elf_bytes_fn elf_bytes_factory)
@@ -72,3 +73,4 @@ void test_verifier_int_ptr(void) { RUN(verifier_int_ptr); } 
void test_verifier_ld_ind(void)               { RUN(verifier_ld_ind); }

void test_verifier_leak_ptr(void)             { RUN(verifier_leak_ptr); }

void test_verifier_map_ptr(void)              { RUN(verifier_map_ptr); }

void test_verifier_map_ret_val(void)          { RUN(verifier_map_ret_val); }

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

0 → 100644
+110 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

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



#include <linux/bpf.h>

#include <bpf/bpf_helpers.h>

#include "../../../include/linux/filter.h"

#include "bpf_misc.h"



struct {

	__uint(type, BPF_MAP_TYPE_HASH);

	__uint(max_entries, 1);

	__type(key, long long);

	__type(value, long long);

} map_hash_8b SEC(".maps");



SEC("socket")

__description("invalid map_fd for function call")

__failure __msg("fd 0 is not pointing to valid bpf_map")

__failure_unpriv

__naked void map_fd_for_function_call(void)

{

	asm volatile ("					\

	r2 = 0;						\

	*(u64*)(r10 - 8) = r2;				\

	r2 = r10;					\

	r2 += -8;					\

	.8byte %[ld_map_fd];				\

	.8byte 0;					\

	call %[bpf_map_delete_elem];			\

	exit;						\

"	:

	: __imm(bpf_map_delete_elem),

	  __imm_insn(ld_map_fd, BPF_RAW_INSN(BPF_LD | BPF_DW | BPF_IMM, BPF_REG_1, BPF_PSEUDO_MAP_FD, 0, 0))

	: __clobber_all);

}



SEC("socket")

__description("don't check return value before access")

__failure __msg("R0 invalid mem access 'map_value_or_null'")

__failure_unpriv

__naked void check_return_value_before_access(void)

{

	asm volatile ("					\

	r1 = 0;						\

	*(u64*)(r10 - 8) = r1;				\

	r2 = r10;					\

	r2 += -8;					\

	r1 = %[map_hash_8b] ll;				\

	call %[bpf_map_lookup_elem];			\

	r1 = 0;						\

	*(u64*)(r0 + 0) = r1;				\

	exit;						\

"	:

	: __imm(bpf_map_lookup_elem),

	  __imm_addr(map_hash_8b)

	: __clobber_all);

}



SEC("socket")

__description("access memory with incorrect alignment")

__failure __msg("misaligned value access")

__failure_unpriv

__flag(BPF_F_STRICT_ALIGNMENT)

__naked void access_memory_with_incorrect_alignment_1(void)

{

	asm volatile ("					\

	r1 = 0;						\

	*(u64*)(r10 - 8) = r1;				\

	r2 = r10;					\

	r2 += -8;					\

	r1 = %[map_hash_8b] ll;				\

	call %[bpf_map_lookup_elem];			\

	if r0 == 0 goto l0_%=;				\

	r1 = 0;						\

	*(u64*)(r0 + 4) = r1;				\

l0_%=:	exit;						\

"	:

	: __imm(bpf_map_lookup_elem),

	  __imm_addr(map_hash_8b)

	: __clobber_all);

}



SEC("socket")

__description("sometimes access memory with incorrect alignment")

__failure __msg("R0 invalid mem access")

__msg_unpriv("R0 leaks addr")

__flag(BPF_F_STRICT_ALIGNMENT)

__naked void access_memory_with_incorrect_alignment_2(void)

{

	asm volatile ("					\

	r1 = 0;						\

	*(u64*)(r10 - 8) = r1;				\

	r2 = r10;					\

	r2 += -8;					\

	r1 = %[map_hash_8b] ll;				\

	call %[bpf_map_lookup_elem];			\

	if r0 == 0 goto l0_%=;				\

	r1 = 0;						\

	*(u64*)(r0 + 0) = r1;				\

	exit;						\

l0_%=:	r1 = 1;						\

	*(u64*)(r0 + 0) = r1;				\

	exit;						\

"	:

	: __imm(bpf_map_lookup_elem),

	  __imm_addr(map_hash_8b)

	: __clobber_all);

}



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

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

deleted100644 → 0
+0 −65
Original line number Diff line number Diff line 
{

	"invalid map_fd for function call",

	.insns = {

	BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),

	BPF_ALU64_REG(BPF_MOV, BPF_REG_2, BPF_REG_10),

	BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),

	BPF_LD_MAP_FD(BPF_REG_1, 0),

	BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_delete_elem),

	BPF_EXIT_INSN(),

	},

	.errstr = "fd 0 is not pointing to valid bpf_map",

	.result = REJECT,

},

{

	"don't check return value before access",

	.insns = {

	BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),

	BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),

	BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),

	BPF_LD_MAP_FD(BPF_REG_1, 0),

	BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),

	BPF_ST_MEM(BPF_DW, BPF_REG_0, 0, 0),

	BPF_EXIT_INSN(),

	},

	.fixup_map_hash_8b = { 3 },

	.errstr = "R0 invalid mem access 'map_value_or_null'",

	.result = REJECT,

},

{

	"access memory with incorrect alignment",

	.insns = {

	BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),

	BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),

	BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),

	BPF_LD_MAP_FD(BPF_REG_1, 0),

	BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),

	BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),

	BPF_ST_MEM(BPF_DW, BPF_REG_0, 4, 0),

	BPF_EXIT_INSN(),

	},

	.fixup_map_hash_8b = { 3 },

	.errstr = "misaligned value access",

	.result = REJECT,

	.flags = F_LOAD_WITH_STRICT_ALIGNMENT,

},

{

	"sometimes access memory with incorrect alignment",

	.insns = {

	BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),

	BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),

	BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),

	BPF_LD_MAP_FD(BPF_REG_1, 0),

	BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),

	BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),

	BPF_ST_MEM(BPF_DW, BPF_REG_0, 0, 0),

	BPF_EXIT_INSN(),

	BPF_ST_MEM(BPF_DW, BPF_REG_0, 0, 1),

	BPF_EXIT_INSN(),

	},

	.fixup_map_hash_8b = { 3 },

	.errstr = "R0 invalid mem access",

	.errstr_unpriv = "R0 leaks addr",

	.result = REJECT,

	.flags = F_LOAD_WITH_STRICT_ALIGNMENT,

},