On Mon, 5 Sept 2022 at 16:36, Roberto Sassu roberto.sassu@huaweicloud.com wrote:
From: Roberto Sassu roberto.sassu@huawei.com
Add verifier tests for bpf_lookup_*_key() and bpf_key_put(), to ensure that acquired key references stored in the bpf_key structure are released, that a non-NULL bpf_key pointer is passed to bpf_key_put(), and that key references are not leaked.
Also, slightly modify test_verifier.c, to find the BTF ID of the attach point for the LSM program type (currently, it is done only for TRACING).
Signed-off-by: Roberto Sassu roberto.sassu@huawei.com
Acked-by: Kumar Kartikeya Dwivedi memxor@gmail.com
tools/testing/selftests/bpf/config | 1 + tools/testing/selftests/bpf/test_verifier.c | 3 +- .../selftests/bpf/verifier/ref_tracking.c | 139 ++++++++++++++++++ 3 files changed, 142 insertions(+), 1 deletion(-)
diff --git a/tools/testing/selftests/bpf/config b/tools/testing/selftests/bpf/config index 0fdd11e6b742..add5a5a919b4 100644 --- a/tools/testing/selftests/bpf/config +++ b/tools/testing/selftests/bpf/config @@ -30,6 +30,7 @@ CONFIG_IPV6_GRE=y CONFIG_IPV6_SEG6_BPF=y CONFIG_IPV6_SIT=y CONFIG_IPV6_TUNNEL=y +CONFIG_KEYS=y CONFIG_LIRC=y CONFIG_LWTUNNEL=y CONFIG_MPLS=y diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c index f9d553fbf68a..2dbcbf363c18 100644 --- a/tools/testing/selftests/bpf/test_verifier.c +++ b/tools/testing/selftests/bpf/test_verifier.c @@ -1498,7 +1498,8 @@ static void do_test_single(struct bpf_test *test, bool unpriv, opts.log_level = DEFAULT_LIBBPF_LOG_LEVEL; opts.prog_flags = pflags;
if (prog_type == BPF_PROG_TYPE_TRACING && test->kfunc) {
if ((prog_type == BPF_PROG_TYPE_TRACING ||prog_type == BPF_PROG_TYPE_LSM) && test->kfunc) { int attach_btf_id; attach_btf_id = libbpf_find_vmlinux_btf_id(test->kfunc,diff --git a/tools/testing/selftests/bpf/verifier/ref_tracking.c b/tools/testing/selftests/bpf/verifier/ref_tracking.c index 57a83d763ec1..f18ce867271f 100644 --- a/tools/testing/selftests/bpf/verifier/ref_tracking.c +++ b/tools/testing/selftests/bpf/verifier/ref_tracking.c @@ -84,6 +84,145 @@ .errstr = "Unreleased reference", .result = REJECT, }, +{
"reference tracking: acquire/release user key reference",.insns = {BPF_MOV64_IMM(BPF_REG_1, -3),BPF_MOV64_IMM(BPF_REG_2, 0),BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0),BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0),BPF_MOV64_IMM(BPF_REG_0, 0),BPF_EXIT_INSN(),},.prog_type = BPF_PROG_TYPE_LSM,.kfunc = "bpf",.expected_attach_type = BPF_LSM_MAC,.flags = BPF_F_SLEEPABLE,.fixup_kfunc_btf_id = {{ "bpf_lookup_user_key", 2 },{ "bpf_key_put", 5 },},.result = ACCEPT,+}, +{
"reference tracking: acquire/release system key reference",.insns = {BPF_MOV64_IMM(BPF_REG_1, 1),BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0),BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0),BPF_MOV64_IMM(BPF_REG_0, 0),BPF_EXIT_INSN(),},.prog_type = BPF_PROG_TYPE_LSM,.kfunc = "bpf",.expected_attach_type = BPF_LSM_MAC,.flags = BPF_F_SLEEPABLE,.fixup_kfunc_btf_id = {{ "bpf_lookup_system_key", 1 },{ "bpf_key_put", 4 },},.result = ACCEPT,+}, +{
"reference tracking: release user key reference without check",.insns = {BPF_MOV64_IMM(BPF_REG_1, -3),BPF_MOV64_IMM(BPF_REG_2, 0),BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0),BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0),BPF_MOV64_IMM(BPF_REG_0, 0),BPF_EXIT_INSN(),},.prog_type = BPF_PROG_TYPE_LSM,.kfunc = "bpf",.expected_attach_type = BPF_LSM_MAC,.flags = BPF_F_SLEEPABLE,.errstr = "arg#0 pointer type STRUCT bpf_key must point to scalar, or struct with scalar",.fixup_kfunc_btf_id = {{ "bpf_lookup_user_key", 2 },{ "bpf_key_put", 4 },},.result = REJECT,+}, +{
"reference tracking: release system key reference without check",.insns = {BPF_MOV64_IMM(BPF_REG_1, 1),BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0),BPF_MOV64_REG(BPF_REG_1, BPF_REG_0),BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0),BPF_MOV64_IMM(BPF_REG_0, 0),BPF_EXIT_INSN(),},.prog_type = BPF_PROG_TYPE_LSM,.kfunc = "bpf",.expected_attach_type = BPF_LSM_MAC,.flags = BPF_F_SLEEPABLE,.errstr = "arg#0 pointer type STRUCT bpf_key must point to scalar, or struct with scalar",.fixup_kfunc_btf_id = {{ "bpf_lookup_system_key", 1 },{ "bpf_key_put", 3 },},.result = REJECT,+}, +{
"reference tracking: release with NULL key pointer",.insns = {BPF_MOV64_IMM(BPF_REG_1, 0),BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0),BPF_MOV64_IMM(BPF_REG_0, 0),BPF_EXIT_INSN(),},.prog_type = BPF_PROG_TYPE_LSM,.kfunc = "bpf",.expected_attach_type = BPF_LSM_MAC,.flags = BPF_F_SLEEPABLE,.errstr = "arg#0 pointer type STRUCT bpf_key must point to scalar, or struct with scalar",.fixup_kfunc_btf_id = {{ "bpf_key_put", 1 },},.result = REJECT,+}, +{
"reference tracking: leak potential reference to user key",.insns = {BPF_MOV64_IMM(BPF_REG_1, -3),BPF_MOV64_IMM(BPF_REG_2, 0),BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0),BPF_EXIT_INSN(),},.prog_type = BPF_PROG_TYPE_LSM,.kfunc = "bpf",.expected_attach_type = BPF_LSM_MAC,.flags = BPF_F_SLEEPABLE,.errstr = "Unreleased reference",.fixup_kfunc_btf_id = {{ "bpf_lookup_user_key", 2 },},.result = REJECT,+}, +{
"reference tracking: leak potential reference to system key",.insns = {BPF_MOV64_IMM(BPF_REG_1, 1),BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, BPF_PSEUDO_KFUNC_CALL, 0, 0),BPF_EXIT_INSN(),},.prog_type = BPF_PROG_TYPE_LSM,.kfunc = "bpf",.expected_attach_type = BPF_LSM_MAC,.flags = BPF_F_SLEEPABLE,.errstr = "Unreleased reference",.fixup_kfunc_btf_id = {{ "bpf_lookup_system_key", 1 },},.result = REJECT,+}, { "reference tracking: release reference without check", .insns = { -- 2.25.1