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bpf: add various verifier test cases for self-tests

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Add a couple of test cases, for example, probing for xadd on a spilled
pointer to packet and map_value_adj register, various other map_value_adj
tests including the unaligned load/store, and trying out pointer arithmetic
on map_value_adj register itself. For the unaligned load/store, we need
to figure out whether the architecture has efficient unaligned access and
need to mark affected tests accordingly.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Daniel Borkmann 2017-03-31 02:24:04 +02:00 committed by David S. Miller
parent 79adffcd64
commit 02ea80b185
3 changed files with 283 additions and 6 deletions
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10
tools/include/linux/filter.h
View File

@ -168,6 +168,16 @@
.off = OFF, \
.imm = 0 })
/* Atomic memory add, *(uint *)(dst_reg + off16) += src_reg */
#define BPF_STX_XADD(SIZE, DST, SRC, OFF) \
((struct bpf_insn) { \
.code = BPF_STX | BPF_SIZE(SIZE) | BPF_XADD, \
.dst_reg = DST, \
.src_reg = SRC, \
.off = OFF, \
.imm = 0 })
/* Memory store, *(uint *) (dst_reg + off16) = imm32 */
#define BPF_ST_MEM(SIZE, DST, OFF, IMM) \

9
tools/testing/selftests/bpf/Makefile
View File

@ -1,7 +1,14 @@
LIBDIR := ../../../lib
BPFDIR := $(LIBDIR)/bpf
APIDIR := ../../../include/uapi
GENDIR := ../../../../include/generated
GENHDR := $(GENDIR)/autoconf.h
CFLAGS += -Wall -O2 -I../../../include/uapi -I$(LIBDIR)
ifneq ($(wildcard $(GENHDR)),)
GENFLAGS := -DHAVE_GENHDR
endif
CFLAGS += -Wall -O2 -I$(APIDIR) -I$(LIBDIR) -I$(GENDIR) $(GENFLAGS)
LDLIBS += -lcap
TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map

270
tools/testing/selftests/bpf/test_verifier.c
View File

@ -30,6 +30,14 @@
#include <bpf/bpf.h>
#ifdef HAVE_GENHDR
# include "autoconf.h"
#else
# if defined(__i386) || defined(__x86_64) || defined(__s390x__) || defined(__aarch64__)
# define CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS 1
# endif
#endif
#include "../../../include/linux/filter.h"
#ifndef ARRAY_SIZE
@ -39,6 +47,8 @@
#define MAX_INSNS 512
#define MAX_FIXUPS 8
#define F_NEEDS_EFFICIENT_UNALIGNED_ACCESS (1 << 0)
struct bpf_test {
const char *descr;
struct bpf_insn insns[MAX_INSNS];
@ -53,6 +63,7 @@ struct bpf_test {
REJECT
} result, result_unpriv;
enum bpf_prog_type prog_type;
uint8_t flags;
};
/* Note we want this to be 64 bit aligned so that the end of our array is
@ -2431,6 +2442,30 @@ static struct bpf_test tests[] = {
.result = ACCEPT,
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
"direct packet access: test15 (spill with xadd)",
.insns = {
BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
offsetof(struct __sk_buff, data)),
BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
offsetof(struct __sk_buff, data_end)),
BPF_MOV64_REG(BPF_REG_0, BPF_REG_2),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 8),
BPF_JMP_REG(BPF_JGT, BPF_REG_0, BPF_REG_3, 8),
BPF_MOV64_IMM(BPF_REG_5, 4096),
BPF_MOV64_REG(BPF_REG_4, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, -8),
BPF_STX_MEM(BPF_DW, BPF_REG_4, BPF_REG_2, 0),
BPF_STX_XADD(BPF_DW, BPF_REG_4, BPF_REG_5, 0),
BPF_LDX_MEM(BPF_DW, BPF_REG_2, BPF_REG_4, 0),
BPF_STX_MEM(BPF_W, BPF_REG_2, BPF_REG_5, 0),
BPF_MOV64_IMM(BPF_REG_0, 0),
BPF_EXIT_INSN(),
},
.errstr = "R2 invalid mem access 'inv'",
.result = REJECT,
.prog_type = BPF_PROG_TYPE_SCHED_CLS,
},
{
"helper access to packet: test1, valid packet_ptr range",
.insns = {
@ -2934,6 +2969,7 @@ static struct bpf_test tests[] = {
.errstr_unpriv = "R0 pointer arithmetic prohibited",
.result_unpriv = REJECT,
.result = ACCEPT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
{
"valid map access into an array with a variable",
@ -2957,6 +2993,7 @@ static struct bpf_test tests[] = {
.errstr_unpriv = "R0 pointer arithmetic prohibited",
.result_unpriv = REJECT,
.result = ACCEPT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
{
"valid map access into an array with a signed variable",
@ -2984,6 +3021,7 @@ static struct bpf_test tests[] = {
.errstr_unpriv = "R0 pointer arithmetic prohibited",
.result_unpriv = REJECT,
.result = ACCEPT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
{
"invalid map access into an array with a constant",
@ -3025,6 +3063,7 @@ static struct bpf_test tests[] = {
.errstr = "R0 min value is outside of the array range",
.result_unpriv = REJECT,
.result = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
{
"invalid map access into an array with a variable",
@ -3048,6 +3087,7 @@ static struct bpf_test tests[] = {
.errstr = "R0 min value is negative, either use unsigned index or do a if (index >=0) check.",
.result_unpriv = REJECT,
.result = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
{
"invalid map access into an array with no floor check",
@ -3074,6 +3114,7 @@ static struct bpf_test tests[] = {
.errstr = "R0 min value is negative, either use unsigned index or do a if (index >=0) check.",
.result_unpriv = REJECT,
.result = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
{
"invalid map access into an array with a invalid max check",
@ -3100,6 +3141,7 @@ static struct bpf_test tests[] = {
.errstr = "invalid access to map value, value_size=48 off=44 size=8",
.result_unpriv = REJECT,
.result = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
{
"invalid map access into an array with a invalid max check",
@ -3129,6 +3171,7 @@ static struct bpf_test tests[] = {
.errstr = "R0 min value is negative, either use unsigned index or do a if (index >=0) check.",
.result_unpriv = REJECT,
.result = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
{
"multiple registers share map_lookup_elem result",
@ -3252,6 +3295,7 @@ static struct bpf_test tests[] = {
.result = REJECT,
.errstr_unpriv = "R0 pointer arithmetic prohibited",
.result_unpriv = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
{
"constant register |= constant should keep constant type",
@ -3981,7 +4025,208 @@ static struct bpf_test tests[] = {
.result_unpriv = REJECT,
},
{
"map element value (adjusted) is preserved across register spilling",
"map element value or null is marked on register spilling",
.insns = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -152),
BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, 0),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
BPF_LDX_MEM(BPF_DW, BPF_REG_3, BPF_REG_1, 0),
BPF_ST_MEM(BPF_DW, BPF_REG_3, 0, 42),
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
.errstr_unpriv = "R0 leaks addr",
.result = ACCEPT,
.result_unpriv = REJECT,
},
{
"map element value store of cleared call register",
.insns = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
BPF_STX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, 0),
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
.errstr_unpriv = "R1 !read_ok",
.errstr = "R1 !read_ok",
.result = REJECT,
.result_unpriv = REJECT,
},
{
"map element value with unaligned store",
.insns = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 17),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 3),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 0, 42),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 2, 43),
BPF_ST_MEM(BPF_DW, BPF_REG_0, -2, 44),
BPF_MOV64_REG(BPF_REG_8, BPF_REG_0),
BPF_ST_MEM(BPF_DW, BPF_REG_8, 0, 32),
BPF_ST_MEM(BPF_DW, BPF_REG_8, 2, 33),
BPF_ST_MEM(BPF_DW, BPF_REG_8, -2, 34),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_8, 5),
BPF_ST_MEM(BPF_DW, BPF_REG_8, 0, 22),
BPF_ST_MEM(BPF_DW, BPF_REG_8, 4, 23),
BPF_ST_MEM(BPF_DW, BPF_REG_8, -7, 24),
BPF_MOV64_REG(BPF_REG_7, BPF_REG_8),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_7, 3),
BPF_ST_MEM(BPF_DW, BPF_REG_7, 0, 22),
BPF_ST_MEM(BPF_DW, BPF_REG_7, 4, 23),
BPF_ST_MEM(BPF_DW, BPF_REG_7, -4, 24),
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
.errstr_unpriv = "R0 pointer arithmetic prohibited",
.result = ACCEPT,
.result_unpriv = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
{
"map element value with unaligned load",
.insns = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 11),
BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 0),
BPF_JMP_IMM(BPF_JGE, BPF_REG_1, MAX_ENTRIES, 9),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 3),
BPF_LDX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
BPF_LDX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 2),
BPF_MOV64_REG(BPF_REG_8, BPF_REG_0),
BPF_LDX_MEM(BPF_DW, BPF_REG_7, BPF_REG_8, 0),
BPF_LDX_MEM(BPF_DW, BPF_REG_7, BPF_REG_8, 2),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 5),
BPF_LDX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 0),
BPF_LDX_MEM(BPF_DW, BPF_REG_7, BPF_REG_0, 4),
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
.errstr_unpriv = "R0 pointer arithmetic prohibited",
.result = ACCEPT,
.result_unpriv = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
{
"map element value illegal alu op, 1",
.insns = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
BPF_ALU64_IMM(BPF_AND, BPF_REG_0, 8),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 0, 22),
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
.errstr_unpriv = "R0 pointer arithmetic prohibited",
.errstr = "invalid mem access 'inv'",
.result = REJECT,
.result_unpriv = REJECT,
},
{
"map element value illegal alu op, 2",
.insns = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
BPF_ALU32_IMM(BPF_ADD, BPF_REG_0, 0),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 0, 22),
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
.errstr_unpriv = "R0 pointer arithmetic prohibited",
.errstr = "invalid mem access 'inv'",
.result = REJECT,
.result_unpriv = REJECT,
},
{
"map element value illegal alu op, 3",
.insns = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
BPF_ALU64_IMM(BPF_DIV, BPF_REG_0, 42),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 0, 22),
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
.errstr_unpriv = "R0 pointer arithmetic prohibited",
.errstr = "invalid mem access 'inv'",
.result = REJECT,
.result_unpriv = REJECT,
},
{
"map element value illegal alu op, 4",
.insns = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
BPF_ENDIAN(BPF_FROM_BE, BPF_REG_0, 64),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 0, 22),
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
.errstr_unpriv = "R0 pointer arithmetic prohibited",
.errstr = "invalid mem access 'inv'",
.result = REJECT,
.result_unpriv = REJECT,
},
{
"map element value illegal alu op, 5",
.insns = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_ST_MEM(BPF_DW, BPF_REG_2, 0, 0),
BPF_LD_MAP_FD(BPF_REG_1, 0),
BPF_EMIT_CALL(BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 7),
BPF_MOV64_IMM(BPF_REG_3, 4096),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_0, 0),
BPF_STX_XADD(BPF_DW, BPF_REG_2, BPF_REG_3, 0),
BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_2, 0),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 0, 22),
BPF_EXIT_INSN(),
},
.fixup_map2 = { 3 },
.errstr_unpriv = "R0 invalid mem access 'inv'",
.errstr = "R0 invalid mem access 'inv'",
.result = REJECT,
.result_unpriv = REJECT,
},
{
"map element value is preserved across register spilling",
.insns = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
@ -4003,6 +4248,7 @@ static struct bpf_test tests[] = {
.errstr_unpriv = "R0 pointer arithmetic prohibited",
.result = ACCEPT,
.result_unpriv = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
{
"helper access to variable memory: stack, bitwise AND + JMP, correct bounds",
@ -4441,6 +4687,7 @@ static struct bpf_test tests[] = {
.errstr = "R0 min value is negative, either use unsigned index or do a if (index >=0) check.",
.result = REJECT,
.result_unpriv = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
},
{
"invalid range check",
@ -4472,6 +4719,7 @@ static struct bpf_test tests[] = {
.errstr = "R0 min value is negative, either use unsigned index or do a if (index >=0) check.",
.result = REJECT,
.result_unpriv = REJECT,
.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
}
};
@ -4550,11 +4798,11 @@ static void do_test_fixup(struct bpf_test *test, struct bpf_insn *prog,
static void do_test_single(struct bpf_test *test, bool unpriv,
int *passes, int *errors)
{
int fd_prog, expected_ret, reject_from_alignment;
struct bpf_insn *prog = test->insns;
int prog_len = probe_filter_length(prog);
int prog_type = test->prog_type;
int fd_f1 = -1, fd_f2 = -1, fd_f3 = -1;
int fd_prog, expected_ret;
const char *expected_err;
do_test_fixup(test, prog, &fd_f1, &fd_f2, &fd_f3);
@ -4567,8 +4815,19 @@ static void do_test_single(struct bpf_test *test, bool unpriv,
test->result_unpriv : test->result;
expected_err = unpriv && test->errstr_unpriv ?
test->errstr_unpriv : test->errstr;
reject_from_alignment = fd_prog < 0 &&
(test->flags & F_NEEDS_EFFICIENT_UNALIGNED_ACCESS) &&
strstr(bpf_vlog, "Unknown alignment.");
#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
if (reject_from_alignment) {
printf("FAIL\nFailed due to alignment despite having efficient unaligned access: '%s'!\n",
strerror(errno));
goto fail_log;
}
#endif
if (expected_ret == ACCEPT) {
if (fd_prog < 0) {
if (fd_prog < 0 && !reject_from_alignment) {
printf("FAIL\nFailed to load prog '%s'!\n",
strerror(errno));
goto fail_log;
@ -4578,14 +4837,15 @@ static void do_test_single(struct bpf_test *test, bool unpriv,
printf("FAIL\nUnexpected success to load!\n");
goto fail_log;
}
if (!strstr(bpf_vlog, expected_err)) {
if (!strstr(bpf_vlog, expected_err) && !reject_from_alignment) {
printf("FAIL\nUnexpected error message!\n");
goto fail_log;
}
}
(*passes)++;
printf("OK\n");
printf("OK%s\n", reject_from_alignment ?
" (NOTE: reject due to unknown alignment)" : "");
close_fds:
close(fd_prog);
close(fd_f1);