* [PATCH bpf 0/4] BPF fixes and tests
@ 2018-10-31 23:05 Daniel Borkmann
2018-10-31 23:05 ` [PATCH bpf 1/4] bpf: fix partial copy of map_ptr when dst is scalar Daniel Borkmann
` (4 more replies)
0 siblings, 5 replies; 9+ messages in thread
From: Daniel Borkmann @ 2018-10-31 23:05 UTC (permalink / raw)
To: ast; +Cc: netdev, Daniel Borkmann
The series contains two fixes in BPF core and test cases. For details
please see individual patches. Thanks!
Daniel Borkmann (4):
bpf: fix partial copy of map_ptr when dst is scalar
bpf: don't set id on after map lookup with ptr_to_map_val return
bpf: add various test cases to test_verifier
bpf: test make sure to run unpriv test cases in test_verifier
include/linux/bpf_verifier.h | 3 +
kernel/bpf/verifier.c | 21 +-
tools/testing/selftests/bpf/test_verifier.c | 321 +++++++++++++++++++++++++---
3 files changed, 305 insertions(+), 40 deletions(-)
--
2.9.5
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH bpf 1/4] bpf: fix partial copy of map_ptr when dst is scalar
2018-10-31 23:05 [PATCH bpf 0/4] BPF fixes and tests Daniel Borkmann
@ 2018-10-31 23:05 ` Daniel Borkmann
2018-11-01 19:17 ` Edward Cree
2018-10-31 23:05 ` [PATCH bpf 2/4] bpf: don't set id on after map lookup with ptr_to_map_val return Daniel Borkmann
` (3 subsequent siblings)
4 siblings, 1 reply; 9+ messages in thread
From: Daniel Borkmann @ 2018-10-31 23:05 UTC (permalink / raw)
To: ast; +Cc: netdev, Daniel Borkmann, Edward Cree
ALU operations on pointers such as scalar_reg += map_value_ptr are
handled in adjust_ptr_min_max_vals(). Problem is however that map_ptr
and range in the register state share a union, so transferring state
through dst_reg->range = ptr_reg->range is just buggy as any new
map_ptr in the dst_reg is then truncated (or null) for subsequent
checks. Fix this by adding a raw member and use it for copying state
over to dst_reg.
Fixes: f1174f77b50c ("bpf/verifier: rework value tracking")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Edward Cree <ecree@solarflare.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
---
include/linux/bpf_verifier.h | 3 +++
kernel/bpf/verifier.c | 10 ++++++----
2 files changed, 9 insertions(+), 4 deletions(-)
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
index 9e8056e..d93e897 100644
--- a/include/linux/bpf_verifier.h
+++ b/include/linux/bpf_verifier.h
@@ -51,6 +51,9 @@ struct bpf_reg_state {
* PTR_TO_MAP_VALUE_OR_NULL
*/
struct bpf_map *map_ptr;
+
+ /* Max size from any of the above. */
+ unsigned long raw;
};
/* Fixed part of pointer offset, pointer types only */
s32 off;
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 171a2c8..774fa40 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -3046,7 +3046,7 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env,
dst_reg->umax_value = umax_ptr;
dst_reg->var_off = ptr_reg->var_off;
dst_reg->off = ptr_reg->off + smin_val;
- dst_reg->range = ptr_reg->range;
+ dst_reg->raw = ptr_reg->raw;
break;
}
/* A new variable offset is created. Note that off_reg->off
@@ -3076,10 +3076,11 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env,
}
dst_reg->var_off = tnum_add(ptr_reg->var_off, off_reg->var_off);
dst_reg->off = ptr_reg->off;
+ dst_reg->raw = ptr_reg->raw;
if (reg_is_pkt_pointer(ptr_reg)) {
dst_reg->id = ++env->id_gen;
/* something was added to pkt_ptr, set range to zero */
- dst_reg->range = 0;
+ dst_reg->raw = 0;
}
break;
case BPF_SUB:
@@ -3108,7 +3109,7 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env,
dst_reg->var_off = ptr_reg->var_off;
dst_reg->id = ptr_reg->id;
dst_reg->off = ptr_reg->off - smin_val;
- dst_reg->range = ptr_reg->range;
+ dst_reg->raw = ptr_reg->raw;
break;
}
/* A new variable offset is created. If the subtrahend is known
@@ -3134,11 +3135,12 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env,
}
dst_reg->var_off = tnum_sub(ptr_reg->var_off, off_reg->var_off);
dst_reg->off = ptr_reg->off;
+ dst_reg->raw = ptr_reg->raw;
if (reg_is_pkt_pointer(ptr_reg)) {
dst_reg->id = ++env->id_gen;
/* something was added to pkt_ptr, set range to zero */
if (smin_val < 0)
- dst_reg->range = 0;
+ dst_reg->raw = 0;
}
break;
case BPF_AND:
--
2.9.5
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH bpf 2/4] bpf: don't set id on after map lookup with ptr_to_map_val return
2018-10-31 23:05 [PATCH bpf 0/4] BPF fixes and tests Daniel Borkmann
2018-10-31 23:05 ` [PATCH bpf 1/4] bpf: fix partial copy of map_ptr when dst is scalar Daniel Borkmann
@ 2018-10-31 23:05 ` Daniel Borkmann
2018-11-01 1:11 ` Roman Gushchin
2018-10-31 23:05 ` [PATCH bpf 3/4] bpf: add various test cases to test_verifier Daniel Borkmann
` (2 subsequent siblings)
4 siblings, 1 reply; 9+ messages in thread
From: Daniel Borkmann @ 2018-10-31 23:05 UTC (permalink / raw)
To: ast; +Cc: netdev, Daniel Borkmann, Roman Gushchin
In the verifier there is no such semantics where registers with
PTR_TO_MAP_VALUE type have an id assigned to them. This is only
used in PTR_TO_MAP_VALUE_OR_NULL and later on nullified once the
test against NULL has been pattern matched and type transformed
into PTR_TO_MAP_VALUE.
Fixes: 3e6a4b3e0289 ("bpf/verifier: introduce BPF_PTR_TO_MAP_VALUE")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Roman Gushchin <guro@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
---
kernel/bpf/verifier.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 774fa40..1971ca32 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -2852,10 +2852,6 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn
regs[BPF_REG_0].type = NOT_INIT;
} else if (fn->ret_type == RET_PTR_TO_MAP_VALUE_OR_NULL ||
fn->ret_type == RET_PTR_TO_MAP_VALUE) {
- if (fn->ret_type == RET_PTR_TO_MAP_VALUE)
- regs[BPF_REG_0].type = PTR_TO_MAP_VALUE;
- else
- regs[BPF_REG_0].type = PTR_TO_MAP_VALUE_OR_NULL;
/* There is no offset yet applied, variable or fixed */
mark_reg_known_zero(env, regs, BPF_REG_0);
/* remember map_ptr, so that check_map_access()
@@ -2868,7 +2864,12 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn
return -EINVAL;
}
regs[BPF_REG_0].map_ptr = meta.map_ptr;
- regs[BPF_REG_0].id = ++env->id_gen;
+ if (fn->ret_type == RET_PTR_TO_MAP_VALUE) {
+ regs[BPF_REG_0].type = PTR_TO_MAP_VALUE;
+ } else {
+ regs[BPF_REG_0].type = PTR_TO_MAP_VALUE_OR_NULL;
+ regs[BPF_REG_0].id = ++env->id_gen;
+ }
} else if (fn->ret_type == RET_PTR_TO_SOCKET_OR_NULL) {
int id = acquire_reference_state(env, insn_idx);
if (id < 0)
--
2.9.5
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH bpf 3/4] bpf: add various test cases to test_verifier
2018-10-31 23:05 [PATCH bpf 0/4] BPF fixes and tests Daniel Borkmann
2018-10-31 23:05 ` [PATCH bpf 1/4] bpf: fix partial copy of map_ptr when dst is scalar Daniel Borkmann
2018-10-31 23:05 ` [PATCH bpf 2/4] bpf: don't set id on after map lookup with ptr_to_map_val return Daniel Borkmann
@ 2018-10-31 23:05 ` Daniel Borkmann
2018-10-31 23:05 ` [PATCH bpf 4/4] bpf: test make sure to run unpriv test cases in test_verifier Daniel Borkmann
2018-11-01 0:08 ` [PATCH bpf 0/4] BPF fixes and tests Alexei Starovoitov
4 siblings, 0 replies; 9+ messages in thread
From: Daniel Borkmann @ 2018-10-31 23:05 UTC (permalink / raw)
To: ast; +Cc: netdev, Daniel Borkmann
Add some more map related test cases to test_verifier kselftest
to improve test coverage. Summary: 1012 PASSED, 0 SKIPPED, 0 FAILED
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
---
tools/testing/selftests/bpf/test_verifier.c | 250 ++++++++++++++++++++++++++++
1 file changed, 250 insertions(+)
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index 36f3d30..4c7445d 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -6455,6 +6455,256 @@ static struct bpf_test tests[] = {
.prog_type = BPF_PROG_TYPE_TRACEPOINT,
},
{
+ "map access: known scalar += value_ptr",
+ .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, 3),
+ BPF_MOV64_IMM(BPF_REG_1, 4),
+ BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_0),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_map_array_48b = { 3 },
+ .result = ACCEPT,
+ .retval = 1,
+ },
+ {
+ "map access: value_ptr += known scalar",
+ .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, 3),
+ BPF_MOV64_IMM(BPF_REG_1, 4),
+ BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
+ BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_map_array_48b = { 3 },
+ .result = ACCEPT,
+ .retval = 1,
+ },
+ {
+ "map access: unknown scalar += value_ptr",
+ .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, 4),
+ BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
+ BPF_ALU64_IMM(BPF_AND, BPF_REG_1, 0xf),
+ BPF_ALU64_REG(BPF_ADD, BPF_REG_1, BPF_REG_0),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_map_array_48b = { 3 },
+ .result = ACCEPT,
+ .retval = 1,
+ },
+ {
+ "map access: value_ptr += unknown scalar",
+ .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, 4),
+ BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
+ BPF_ALU64_IMM(BPF_AND, BPF_REG_1, 0xf),
+ BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
+ BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_map_array_48b = { 3 },
+ .result = ACCEPT,
+ .retval = 1,
+ },
+ {
+ "map access: value_ptr += value_ptr",
+ .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_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_0),
+ BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_map_array_48b = { 3 },
+ .result = REJECT,
+ .errstr = "R0 pointer += pointer prohibited",
+ },
+ {
+ "map access: known scalar -= value_ptr",
+ .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, 3),
+ BPF_MOV64_IMM(BPF_REG_1, 4),
+ BPF_ALU64_REG(BPF_SUB, BPF_REG_1, BPF_REG_0),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_map_array_48b = { 3 },
+ .result = REJECT,
+ .errstr = "R1 tried to subtract pointer from scalar",
+ },
+ {
+ "map access: value_ptr -= known scalar",
+ .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, 3),
+ BPF_MOV64_IMM(BPF_REG_1, 4),
+ BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_1),
+ BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_map_array_48b = { 3 },
+ .result = REJECT,
+ .errstr = "R0 min value is outside of the array range",
+ },
+ {
+ "map access: value_ptr -= known scalar, 2",
+ .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, 5),
+ BPF_MOV64_IMM(BPF_REG_1, 6),
+ BPF_MOV64_IMM(BPF_REG_2, 4),
+ BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
+ BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_2),
+ BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_map_array_48b = { 3 },
+ .result = ACCEPT,
+ .retval = 1,
+ },
+ {
+ "map access: unknown scalar -= value_ptr",
+ .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, 4),
+ BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
+ BPF_ALU64_IMM(BPF_AND, BPF_REG_1, 0xf),
+ BPF_ALU64_REG(BPF_SUB, BPF_REG_1, BPF_REG_0),
+ BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_1, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_map_array_48b = { 3 },
+ .result = REJECT,
+ .errstr = "R1 tried to subtract pointer from scalar",
+ },
+ {
+ "map access: value_ptr -= unknown scalar",
+ .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, 4),
+ BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
+ BPF_ALU64_IMM(BPF_AND, BPF_REG_1, 0xf),
+ BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_1),
+ BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_map_array_48b = { 3 },
+ .result = REJECT,
+ .errstr = "R0 min value is negative",
+ },
+ {
+ "map access: value_ptr -= unknown scalar, 2",
+ .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, 8),
+ BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
+ BPF_ALU64_IMM(BPF_AND, BPF_REG_1, 0xf),
+ BPF_ALU64_IMM(BPF_OR, BPF_REG_1, 0x7),
+ BPF_ALU64_REG(BPF_ADD, BPF_REG_0, BPF_REG_1),
+ BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
+ BPF_ALU64_IMM(BPF_AND, BPF_REG_1, 0x7),
+ BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_1),
+ BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_map_array_48b = { 3 },
+ .result = ACCEPT,
+ .retval = 1,
+ },
+ {
+ "map access: value_ptr -= value_ptr",
+ .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_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_0),
+ BPF_LDX_MEM(BPF_B, BPF_REG_1, BPF_REG_0, 0),
+ BPF_MOV64_IMM(BPF_REG_0, 1),
+ BPF_EXIT_INSN(),
+ },
+ .fixup_map_array_48b = { 3 },
+ .result = REJECT,
+ .errstr = "R0 invalid mem access 'inv'",
+ .errstr_unpriv = "R0 pointer -= pointer prohibited",
+ },
+ {
"map lookup helper access to map",
.insns = {
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
--
2.9.5
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH bpf 4/4] bpf: test make sure to run unpriv test cases in test_verifier
2018-10-31 23:05 [PATCH bpf 0/4] BPF fixes and tests Daniel Borkmann
` (2 preceding siblings ...)
2018-10-31 23:05 ` [PATCH bpf 3/4] bpf: add various test cases to test_verifier Daniel Borkmann
@ 2018-10-31 23:05 ` Daniel Borkmann
2018-11-01 0:08 ` [PATCH bpf 0/4] BPF fixes and tests Alexei Starovoitov
4 siblings, 0 replies; 9+ messages in thread
From: Daniel Borkmann @ 2018-10-31 23:05 UTC (permalink / raw)
To: ast; +Cc: netdev, Daniel Borkmann
Right now unprivileged tests are never executed as a BPF test run,
only loaded. Allow for running them as well so that we can check
the outcome and probe for regressions.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
---
tools/testing/selftests/bpf/test_verifier.c | 71 ++++++++++++++++-------------
1 file changed, 40 insertions(+), 31 deletions(-)
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index 4c7445d..6f61df6 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -76,7 +76,7 @@ struct bpf_test {
int fixup_percpu_cgroup_storage[MAX_FIXUPS];
const char *errstr;
const char *errstr_unpriv;
- uint32_t retval;
+ uint32_t retval, retval_unpriv;
enum {
UNDEF,
ACCEPT,
@@ -3084,6 +3084,8 @@ static struct bpf_test tests[] = {
.fixup_prog1 = { 2 },
.result = ACCEPT,
.retval = 42,
+ /* Verifier rewrite for unpriv skips tail call here. */
+ .retval_unpriv = 2,
},
{
"stack pointer arithmetic",
@@ -14149,6 +14151,33 @@ static void do_test_fixup(struct bpf_test *test, enum bpf_map_type prog_type,
}
}
+static int set_admin(bool admin)
+{
+ cap_t caps;
+ const cap_value_t cap_val = CAP_SYS_ADMIN;
+ int ret = -1;
+
+ caps = cap_get_proc();
+ if (!caps) {
+ perror("cap_get_proc");
+ return -1;
+ }
+ if (cap_set_flag(caps, CAP_EFFECTIVE, 1, &cap_val,
+ admin ? CAP_SET : CAP_CLEAR)) {
+ perror("cap_set_flag");
+ goto out;
+ }
+ if (cap_set_proc(caps)) {
+ perror("cap_set_proc");
+ goto out;
+ }
+ ret = 0;
+out:
+ if (cap_free(caps))
+ perror("cap_free");
+ return ret;
+}
+
static void do_test_single(struct bpf_test *test, bool unpriv,
int *passes, int *errors)
{
@@ -14157,6 +14186,7 @@ static void do_test_single(struct bpf_test *test, bool unpriv,
struct bpf_insn *prog = test->insns;
int map_fds[MAX_NR_MAPS];
const char *expected_err;
+ uint32_t expected_val;
uint32_t retval;
int i, err;
@@ -14176,6 +14206,8 @@ 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;
+ expected_val = unpriv && test->retval_unpriv ?
+ test->retval_unpriv : test->retval;
reject_from_alignment = fd_prog < 0 &&
(test->flags & F_NEEDS_EFFICIENT_UNALIGNED_ACCESS) &&
@@ -14209,16 +14241,20 @@ static void do_test_single(struct bpf_test *test, bool unpriv,
__u8 tmp[TEST_DATA_LEN << 2];
__u32 size_tmp = sizeof(tmp);
+ if (unpriv)
+ set_admin(true);
err = bpf_prog_test_run(fd_prog, 1, test->data,
sizeof(test->data), tmp, &size_tmp,
&retval, NULL);
+ if (unpriv)
+ set_admin(false);
if (err && errno != 524/*ENOTSUPP*/ && errno != EPERM) {
printf("Unexpected bpf_prog_test_run error\n");
goto fail_log;
}
- if (!err && retval != test->retval &&
- test->retval != POINTER_VALUE) {
- printf("FAIL retval %d != %d\n", retval, test->retval);
+ if (!err && retval != expected_val &&
+ expected_val != POINTER_VALUE) {
+ printf("FAIL retval %d != %d\n", retval, expected_val);
goto fail_log;
}
}
@@ -14261,33 +14297,6 @@ static bool is_admin(void)
return (sysadmin == CAP_SET);
}
-static int set_admin(bool admin)
-{
- cap_t caps;
- const cap_value_t cap_val = CAP_SYS_ADMIN;
- int ret = -1;
-
- caps = cap_get_proc();
- if (!caps) {
- perror("cap_get_proc");
- return -1;
- }
- if (cap_set_flag(caps, CAP_EFFECTIVE, 1, &cap_val,
- admin ? CAP_SET : CAP_CLEAR)) {
- perror("cap_set_flag");
- goto out;
- }
- if (cap_set_proc(caps)) {
- perror("cap_set_proc");
- goto out;
- }
- ret = 0;
-out:
- if (cap_free(caps))
- perror("cap_free");
- return ret;
-}
-
static void get_unpriv_disabled()
{
char buf[2];
--
2.9.5
^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [PATCH bpf 0/4] BPF fixes and tests
2018-10-31 23:05 [PATCH bpf 0/4] BPF fixes and tests Daniel Borkmann
` (3 preceding siblings ...)
2018-10-31 23:05 ` [PATCH bpf 4/4] bpf: test make sure to run unpriv test cases in test_verifier Daniel Borkmann
@ 2018-11-01 0:08 ` Alexei Starovoitov
4 siblings, 0 replies; 9+ messages in thread
From: Alexei Starovoitov @ 2018-11-01 0:08 UTC (permalink / raw)
To: Daniel Borkmann; +Cc: ast, netdev
On Thu, Nov 01, 2018 at 12:05:51AM +0100, Daniel Borkmann wrote:
> The series contains two fixes in BPF core and test cases. For details
> please see individual patches. Thanks!
>
> Daniel Borkmann (4):
> bpf: fix partial copy of map_ptr when dst is scalar
> bpf: don't set id on after map lookup with ptr_to_map_val return
> bpf: add various test cases to test_verifier
> bpf: test make sure to run unpriv test cases in test_verifier
>
> include/linux/bpf_verifier.h | 3 +
> kernel/bpf/verifier.c | 21 +-
> tools/testing/selftests/bpf/test_verifier.c | 321 +++++++++++++++++++++++++---
> 3 files changed, 305 insertions(+), 40 deletions(-)
Applied to bpf tree, Thanks
... and we achieved very nice milestone... crossed 1000 tests in test_verifier :)
Summary: 1012 PASSED, 0 SKIPPED, 0 FAILED
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH bpf 2/4] bpf: don't set id on after map lookup with ptr_to_map_val return
2018-10-31 23:05 ` [PATCH bpf 2/4] bpf: don't set id on after map lookup with ptr_to_map_val return Daniel Borkmann
@ 2018-11-01 1:11 ` Roman Gushchin
0 siblings, 0 replies; 9+ messages in thread
From: Roman Gushchin @ 2018-11-01 1:11 UTC (permalink / raw)
To: Daniel Borkmann; +Cc: ast, netdev
On Thu, Nov 01, 2018 at 12:05:53AM +0100, Daniel Borkmann wrote:
> In the verifier there is no such semantics where registers with
> PTR_TO_MAP_VALUE type have an id assigned to them. This is only
> used in PTR_TO_MAP_VALUE_OR_NULL and later on nullified once the
> test against NULL has been pattern matched and type transformed
> into PTR_TO_MAP_VALUE.
>
> Fixes: 3e6a4b3e0289 ("bpf/verifier: introduce BPF_PTR_TO_MAP_VALUE")
> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
> Cc: Roman Gushchin <guro@fb.com>
> Acked-by: Alexei Starovoitov <ast@kernel.org>
Looks good to me.
Acked-by: Roman Gushchin <guro@fb.com>
Thanks!
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH bpf 1/4] bpf: fix partial copy of map_ptr when dst is scalar
2018-10-31 23:05 ` [PATCH bpf 1/4] bpf: fix partial copy of map_ptr when dst is scalar Daniel Borkmann
@ 2018-11-01 19:17 ` Edward Cree
2018-11-01 19:18 ` Arnaldo Carvalho de Melo
0 siblings, 1 reply; 9+ messages in thread
From: Edward Cree @ 2018-11-01 19:17 UTC (permalink / raw)
To: Daniel Borkmann, ast; +Cc: netdev
On 31/10/18 23:05, Daniel Borkmann wrote:
> ALU operations on pointers such as scalar_reg += map_value_ptr are
> handled in adjust_ptr_min_max_vals(). Problem is however that map_ptr
> and range in the register state share a union, so transferring state
> through dst_reg->range = ptr_reg->range is just buggy as any new
> map_ptr in the dst_reg is then truncated (or null) for subsequent
> checks. Fix this by adding a raw member and use it for copying state
> over to dst_reg.
>
> Fixes: f1174f77b50c ("bpf/verifier: rework value tracking")
> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
> Cc: Edward Cree <ecree@solarflare.com>
> Acked-by: Alexei Starovoitov <ast@kernel.org>
> ---
Acked-by: Edward Cree <ecree@solarflare.com>
(though I apparently missed the 63-minute window to hit the git record...)
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH bpf 1/4] bpf: fix partial copy of map_ptr when dst is scalar
2018-11-01 19:17 ` Edward Cree
@ 2018-11-01 19:18 ` Arnaldo Carvalho de Melo
0 siblings, 0 replies; 9+ messages in thread
From: Arnaldo Carvalho de Melo @ 2018-11-01 19:18 UTC (permalink / raw)
To: Edward Cree; +Cc: Daniel Borkmann, ast, netdev
Em Thu, Nov 01, 2018 at 07:17:29PM +0000, Edward Cree escreveu:
> On 31/10/18 23:05, Daniel Borkmann wrote:
> > ALU operations on pointers such as scalar_reg += map_value_ptr are
> > handled in adjust_ptr_min_max_vals(). Problem is however that map_ptr
> > and range in the register state share a union, so transferring state
> > through dst_reg->range = ptr_reg->range is just buggy as any new
> > map_ptr in the dst_reg is then truncated (or null) for subsequent
> > checks. Fix this by adding a raw member and use it for copying state
> > over to dst_reg.
> >
> > Fixes: f1174f77b50c ("bpf/verifier: rework value tracking")
> > Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
> > Cc: Edward Cree <ecree@solarflare.com>
> > Acked-by: Alexei Starovoitov <ast@kernel.org>
> > ---
> Acked-by: Edward Cree <ecree@solarflare.com>
> (though I apparently missed the 63-minute window to hit the git record...)
Those guys are fast! :-)
- Arnaldo
^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2018-11-02 4:23 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-10-31 23:05 [PATCH bpf 0/4] BPF fixes and tests Daniel Borkmann
2018-10-31 23:05 ` [PATCH bpf 1/4] bpf: fix partial copy of map_ptr when dst is scalar Daniel Borkmann
2018-11-01 19:17 ` Edward Cree
2018-11-01 19:18 ` Arnaldo Carvalho de Melo
2018-10-31 23:05 ` [PATCH bpf 2/4] bpf: don't set id on after map lookup with ptr_to_map_val return Daniel Borkmann
2018-11-01 1:11 ` Roman Gushchin
2018-10-31 23:05 ` [PATCH bpf 3/4] bpf: add various test cases to test_verifier Daniel Borkmann
2018-10-31 23:05 ` [PATCH bpf 4/4] bpf: test make sure to run unpriv test cases in test_verifier Daniel Borkmann
2018-11-01 0:08 ` [PATCH bpf 0/4] BPF fixes and tests Alexei Starovoitov
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