August 2022 - Linux-kselftest-mirror

[PATCH v14 00/12] bpf: Add kfuncs for PKCS#7 signature verification

by Roberto Sassu

From: Roberto Sassu <roberto.sassu(a)huawei.com> One of the desirable features in security is the ability to restrict import of data to a given system based on data authenticity. If data import can be restricted, it would be possible to enforce a system-wide policy based on the signing keys the system owner trusts. This feature is widely used in the kernel. For example, if the restriction is enabled, kernel modules can be plugged in only if they are signed with a key whose public part is in the primary or secondary keyring. For eBPF, it can be useful as well. For example, it might be useful to authenticate data an eBPF program makes security decisions on. After a discussion in the eBPF mailing list, it was decided that the stated goal should be accomplished by introducing four new kfuncs: bpf_lookup_user_key() and bpf_lookup_system_key(), for retrieving a keyring with keys trusted for signature verification, respectively from its serial and from a pre-determined ID; bpf_key_put(), to release the reference obtained with the former two kfuncs, bpf_verify_pkcs7_signature(), for verifying PKCS#7 signatures. Other than the key serial, bpf_lookup_user_key() also accepts key lookup flags, that influence the behavior of the lookup. bpf_lookup_system_key() accepts pre-determined IDs defined in include/linux/verification.h. bpf_key_put() accepts the new bpf_key structure, introduced to tell whether the other structure member, a key pointer, is valid or not. The reason is that verify_pkcs7_signature() also accepts invalid pointers, set with the pre-determined ID, to select a system-defined keyring. key_put() must be called only for valid key pointers. Since the two key lookup functions allocate memory and one increments a key reference count, they must be used in conjunction with bpf_key_put(). The latter must be called only if the lookup functions returned a non-NULL pointer. The verifier denies the execution of eBPF programs that don't respect this rule. The two key lookup functions should be used in alternative, depending on the use case. While bpf_lookup_user_key() provides great flexibility, it seems suboptimal in terms of security guarantees, as even if the eBPF program is assumed to be trusted, the serial used to obtain the key pointer might come from untrusted user space not choosing one that the system administrator approves to enforce a mandatory policy. bpf_lookup_system_key() instead provides much stronger guarantees, especially if the pre-determined ID is not passed by user space but is hardcoded in the eBPF program, and that program is signed. In this case, bpf_verify_pkcs7_signature() will always perform signature verification with a key that the system administrator approves, i.e. the primary, secondary or platform keyring. Nevertheless, key permission checks need to be done accurately. Since bpf_lookup_user_key() cannot determine how a key will be used by other kfuncs, it has to defer the permission check to the actual kfunc using the key. It does it by calling lookup_user_key() with KEY_DEFER_PERM_CHECK as needed permission. Later, bpf_verify_pkcs7_signature(), if called, completes the permission check by calling key_validate(). It does not need to call key_task_permission() with permission KEY_NEED_SEARCH, as it is already done elsewhere by the key subsystem. Future kfuncs using the bpf_key structure need to implement the proper checks as well. Finally, the last kfunc, bpf_verify_pkcs7_signature(), accepts the data and signature to verify as eBPF dynamic pointers, to minimize the number of kfunc parameters, and the keyring with keys for signature verification as a bpf_key structure, returned by one of the two key lookup functions. bpf_lookup_user_key() and bpf_verify_pkcs7_signature() can be called only from sleepable programs, because of memory allocation and crypto operations. For example, the lsm.s/bpf attach point is suitable, fexit/array_map_update_elem is not. The correctness of implementation of the new kfuncs and of their usage is checked with the introduced tests. The patch set includes a patch from another author (dependency) for sake of completeness. It is organized as follows. Patch 1 from KP Singh allows kfuncs to be used by LSM programs. Patch 2 splits is_dynptr_reg_valid_init() and introduces is_dynptr_type_expected(), to know more precisely the cause of a negative result of a dynamic pointer check. Patch 3 allows dynamic pointers to be used as kfunc parameters. Patch 4 exports bpf_dynptr_get_size(), to obtain the real size of data carried by a dynamic pointer. Patch 5 makes available for new eBPF kfuncs some key-related definitions. Patch 6 introduces the bpf_lookup_*_key() and bpf_key_put() kfuncs. Patch 7 introduces the bpf_verify_pkcs7_signature() kfunc. Patch 8 changes the testing kernel configuration to compile everything as built-in. Finally, patches 9-12 introduce the tests. Changelog v13: - Split is_dynptr_reg_valid_init() and introduce is_dynptr_type_expected() to see if the dynamic pointer type passed as argument to a kfunc is supported (suggested by Kumar) - Add forward declaration of struct key in include/linux/bpf.h (suggested by Song) - Declare mask for key lookup flags, remove key_lookup_flags_check() (suggested by Jarkko and KP) - Allow only certain dynamic pointer types (currently, local) to be passed as argument to kfuncs (suggested by Kumar) - For each dynamic pointer parameter in kfunc, additionally check if the passed pointer is to the stack (suggested by Kumar) - Split the validity/initialization and dynamic pointer type check also in the verifier, and adjust the expected error message in the test (a test for an unexpected dynptr type passed to a helper cannot be added due to missing suitable helpers, but this case has been tested manually) - Add verifier tests to check the dynamic pointers passed as argument to kfuncs (suggested by Kumar) v12: - Put lookup_key and verify_pkcs7_sig tests in deny list for s390x (JIT does not support calling kernel function) v11: - Move stringify_struct() macro to include/linux/btf.h (suggested by Daniel) - Change kernel configuration options in tools/testing/selftests/bpf/config* from =m to =y v10: - Introduce key_lookup_flags_check() and system_keyring_id_check() inline functions to check parameters (suggested by KP) - Fix descriptions and comment of key-related kfuncs (suggested by KP) - Register kfunc set only once (suggested by Alexei) - Move needed kernel options to the architecture-independent configuration for testing v9: - Drop patch to introduce KF_SLEEPABLE kfunc flag (already merged) - Rename valid_ptr member of bpf_key to has_ref (suggested by Daniel) - Check dynamic pointers in kfunc definition with bpf_dynptr_kern struct definition instead of string, to detect structure renames (suggested by Daniel) - Explicitly say that we permit initialized dynamic pointers in kfunc definition (suggested by Daniel) - Remove noinline __weak from kfuncs definition (reported by Daniel) - Simplify key lookup flags check in bpf_lookup_user_key() (suggested by Daniel) - Explain the reason for deferring key permission check (suggested by Daniel) - Allocate memory with GFP_ATOMIC in bpf_lookup_system_key(), and remove KF_SLEEPABLE kfunc flag from kfunc declaration (suggested by Daniel) - Define only one kfunc set and remove the loop for registration (suggested by Alexei) v8: - Define the new bpf_key structure to carry the key pointer and whether that pointer is valid or not (suggested by Daniel) - Drop patch to mark a kfunc parameter with the __maybe_null suffix - Improve documentation of kfuncs - Introduce bpf_lookup_system_key() to obtain a key pointer suitable for verify_pkcs7_signature() (suggested by Daniel) - Use the new kfunc registration API - Drop patch to test the __maybe_null suffix - Add tests for bpf_lookup_system_key() v7: - Add support for using dynamic and NULL pointers in kfunc (suggested by Alexei) - Add new kfunc-related tests v6: - Switch back to key lookup helpers + signature verification (until v5), and defer permission check from bpf_lookup_user_key() to bpf_verify_pkcs7_signature() - Add additional key lookup test to illustrate the usage of the KEY_LOOKUP_CREATE flag and validate the flags (suggested by Daniel) - Make description of flags of bpf_lookup_user_key() more user-friendly (suggested by Daniel) - Fix validation of flags parameter in bpf_lookup_user_key() (reported by Daniel) - Rename bpf_verify_pkcs7_signature() keyring-related parameters to user_keyring and system_keyring to make their purpose more clear - Accept keyring-related parameters of bpf_verify_pkcs7_signature() as alternatives (suggested by KP) - Replace unsigned long type with u64 in helper declaration (suggested by Daniel) - Extend the bpf_verify_pkcs7_signature() test by calling the helper without data, by ensuring that the helper enforces the keyring-related parameters as alternatives, by ensuring that the helper rejects inaccessible and expired keyrings, and by checking all system keyrings - Move bpf_lookup_user_key() and bpf_key_put() usage tests to ref_tracking.c (suggested by John) - Call bpf_lookup_user_key() and bpf_key_put() only in sleepable programs v5: - Move KEY_LOOKUP_ to include/linux/key.h for validation of bpf_verify_pkcs7_signature() parameter - Remove bpf_lookup_user_key() and bpf_key_put() helpers, and the corresponding tests - Replace struct key parameter of bpf_verify_pkcs7_signature() with the keyring serial and lookup flags - Call lookup_user_key() and key_put() in bpf_verify_pkcs7_signature() code, to ensure that the retrieved key is used according to the permission requested at lookup time - Clarified keyring precedence in the description of bpf_verify_pkcs7_signature() (suggested by John) - Remove newline in the second argument of ASSERT_ - Fix helper prototype regular expression in bpf_doc.py v4: - Remove bpf_request_key_by_id(), don't return an invalid pointer that other helpers can use - Pass the keyring ID (without ULONG_MAX, suggested by Alexei) to bpf_verify_pkcs7_signature() - Introduce bpf_lookup_user_key() and bpf_key_put() helpers (suggested by Alexei) - Add lookup_key_norelease test, to ensure that the verifier blocks eBPF programs which don't decrement the key reference count - Parse raw PKCS#7 signature instead of module-style signature in the verify_pkcs7_signature test (suggested by Alexei) - Parse kernel module in user space and pass raw PKCS#7 signature to the eBPF program for signature verification v3: - Rename bpf_verify_signature() back to bpf_verify_pkcs7_signature() to avoid managing different parameters for each signature verification function in one helper (suggested by Daniel) - Use dynamic pointers and export bpf_dynptr_get_size() (suggested by Alexei) - Introduce bpf_request_key_by_id() to give more flexibility to the caller of bpf_verify_pkcs7_signature() to retrieve the appropriate keyring (suggested by Alexei) - Fix test by reordering the gcc command line, always compile sign-file - Improve helper support check mechanism in the test v2: - Rename bpf_verify_pkcs7_signature() to a more generic bpf_verify_signature() and pass the signature type (suggested by KP) - Move the helper and prototype declaration under #ifdef so that user space can probe for support for the helper (suggested by Daniel) - Describe better the keyring types (suggested by Daniel) - Include linux/bpf.h instead of vmlinux.h to avoid implicit or redeclaration - Make the test selfcontained (suggested by Alexei) v1: - Don't define new map flag but introduce simple wrapper of verify_pkcs7_signature() (suggested by Alexei and KP) KP Singh (1): bpf: Allow kfuncs to be used in LSM programs Roberto Sassu (11): bpf: Move dynptr type check to is_dynptr_type_expected() btf: Allow dynamic pointer parameters in kfuncs bpf: Export bpf_dynptr_get_size() KEYS: Move KEY_LOOKUP_ to include/linux/key.h and set KEY_LOOKUP_FLAGS_ALL bpf: Add bpf_lookup_*_key() and bpf_key_put() kfuncs bpf: Add bpf_verify_pkcs7_signature() kfunc selftests/bpf: Compile kernel with everything as built-in selftests/bpf: Add verifier tests for bpf_lookup_*_key() and bpf_key_put() selftests/bpf: Add additional tests for bpf_lookup_*_key() selftests/bpf: Add test for bpf_verify_pkcs7_signature() kfunc selftests/bpf: Add verifier tests for dynamic pointers parameters in kfuncs include/linux/bpf.h | 9 + include/linux/bpf_verifier.h | 5 + include/linux/btf.h | 9 + include/linux/key.h | 4 + include/linux/verification.h | 8 + kernel/bpf/btf.c | 34 ++ kernel/bpf/helpers.c | 2 +- kernel/bpf/verifier.c | 35 +- kernel/trace/bpf_trace.c | 180 ++++++++ security/keys/internal.h | 2 - tools/testing/selftests/bpf/DENYLIST.s390x | 2 + tools/testing/selftests/bpf/Makefile | 14 +- tools/testing/selftests/bpf/config | 32 +- tools/testing/selftests/bpf/config.x86_64 | 7 +- .../testing/selftests/bpf/prog_tests/dynptr.c | 2 +- .../selftests/bpf/prog_tests/lookup_key.c | 112 +++++ .../bpf/prog_tests/verify_pkcs7_sig.c | 399 ++++++++++++++++++ .../selftests/bpf/progs/test_lookup_key.c | 46 ++ .../bpf/progs/test_verify_pkcs7_sig.c | 100 +++++ tools/testing/selftests/bpf/test_verifier.c | 3 +- .../bpf/verifier/kfunc_dynptr_param.c | 72 ++++ .../selftests/bpf/verifier/ref_tracking.c | 139 ++++++ .../testing/selftests/bpf/verify_sig_setup.sh | 104 +++++ 23 files changed, 1285 insertions(+), 35 deletions(-) create mode 100644 tools/testing/selftests/bpf/prog_tests/lookup_key.c create mode 100644 tools/testing/selftests/bpf/prog_tests/verify_pkcs7_sig.c create mode 100644 tools/testing/selftests/bpf/progs/test_lookup_key.c create mode 100644 tools/testing/selftests/bpf/progs/test_verify_pkcs7_sig.c create mode 100644 tools/testing/selftests/bpf/verifier/kfunc_dynptr_param.c create mode 100755 tools/testing/selftests/bpf/verify_sig_setup.sh -- 2.25.1

1 year, 8 months

4
22
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[PATCH v1 0/5] KVM: arm64: Enable ring-based dirty memory tracking

by Gavin Shan

This series enables the ring-based dirty memory tracking for ARM64. The feature has been available and enabled on x86 for a while. It is beneficial when the number of dirty pages is small in a checkpointing system or live migration scenario. More details can be found from fb04a1eddb1a ("KVM: X86: Implement ring-based dirty memory tracking"). The generic part has been comprehensive enough, meaning there isn't too much work, needed to extend it to ARM64. - PATCH[1] enables the feature on ARM64 - PATCH[2-5] improves kvm/selftests/dirty_log_test Testing ======= - kvm/selftests/dirty_log_test - Live migration by QEMU - Host with 4KB or 64KB base page size Gavin Shan (5): KVM: arm64: Enable ring-based dirty memory tracking KVM: selftests: Use host page size to map ring buffer in dirty_log_test KVM: selftests: Dirty host pages in dirty_log_test KVM: selftests: Clear dirty ring states between two modes in dirty_log_test KVM: selftests: Automate choosing dirty ring size in dirty_log_test Documentation/virt/kvm/api.rst | 2 +- arch/arm64/include/uapi/asm/kvm.h | 1 + arch/arm64/kvm/Kconfig | 1 + arch/arm64/kvm/arm.c | 8 ++ tools/testing/selftests/kvm/dirty_log_test.c | 101 ++++++++++++++----- tools/testing/selftests/kvm/lib/kvm_util.c | 2 +- 6 files changed, 88 insertions(+), 27 deletions(-) -- 2.23.0

1 year, 8 months

6
32
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[PATCH 4/6] selftests/sgx: Add SGX selftest augment_via_eaccept_long

by Jarkko Sakkinen

From: Vijay Dhanraj <vijay.dhanraj(a)intel.com> Add a new test case which is same as augment_via_eaccept but adds a larger number of EPC pages to stress test EAUG via EACCEPT. Signed-off-by: Vijay Dhanraj <vijay.dhanraj(a)intel.com> Co-developed-by: Jarkko Sakkinen <jarkko(a)kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko(a)kernel.org> --- v2: - Addressed Reinette's feedback: https://lore.kernel.org/linux-sgx/24bd8e42-ff4e-0090-d9e1-cd81e4807f21@inte… --- tools/testing/selftests/sgx/load.c | 5 +- tools/testing/selftests/sgx/main.c | 141 +++++++++++++++++++++--- tools/testing/selftests/sgx/main.h | 3 +- tools/testing/selftests/sgx/sigstruct.c | 2 +- 4 files changed, 129 insertions(+), 22 deletions(-) diff --git a/tools/testing/selftests/sgx/load.c b/tools/testing/selftests/sgx/load.c index 94bdeac1cf04..7de1b15c90b1 100644 --- a/tools/testing/selftests/sgx/load.c +++ b/tools/testing/selftests/sgx/load.c @@ -171,7 +171,8 @@ uint64_t encl_get_entry(struct encl *encl, const char *symbol) return 0; } -bool encl_load(const char *path, struct encl *encl, unsigned long heap_size) +bool encl_load(const char *path, struct encl *encl, unsigned long heap_size, + unsigned long edmm_size) { const char device_path[] = "/dev/sgx_enclave"; struct encl_segment *seg; @@ -300,7 +301,7 @@ bool encl_load(const char *path, struct encl *encl, unsigned long heap_size) encl->src_size = encl->segment_tbl[j].offset + encl->segment_tbl[j].size; - for (encl->encl_size = 4096; encl->encl_size < encl->src_size; ) + for (encl->encl_size = 4096; encl->encl_size < encl->src_size + edmm_size;) encl->encl_size <<= 1; return true; diff --git a/tools/testing/selftests/sgx/main.c b/tools/testing/selftests/sgx/main.c index 9820b3809c69..867e98502120 100644 --- a/tools/testing/selftests/sgx/main.c +++ b/tools/testing/selftests/sgx/main.c @@ -21,8 +21,15 @@ #include "../kselftest_harness.h" #include "main.h" +/* + * The size was chosen based on a bug report: + * https://lore.kernel.org/linux-sgx/DM8PR11MB55912A7F47A84EC9913A6352F6999@DM… + */ +static const unsigned long EDMM_SIZE_LONG = 8L * 1024L * 1024L * 1024L; // 8 GB +static const unsigned long TIMEOUT_LONG = 900; /* seconds */ static const uint64_t MAGIC = 0x1122334455667788ULL; static const uint64_t MAGIC2 = 0x8877665544332211ULL; + vdso_sgx_enter_enclave_t vdso_sgx_enter_enclave; /* @@ -173,7 +180,8 @@ FIXTURE(enclave) { }; static bool setup_test_encl(unsigned long heap_size, struct encl *encl, - struct __test_metadata *_metadata) + struct __test_metadata *_metadata, + unsigned long edmm_size) { Elf64_Sym *sgx_enter_enclave_sym = NULL; struct vdso_symtab symtab; @@ -183,7 +191,7 @@ static bool setup_test_encl(unsigned long heap_size, struct encl *encl, unsigned int i; void *addr; - if (!encl_load("test_encl.elf", encl, heap_size)) { + if (!encl_load("test_encl.elf", encl, heap_size, edmm_size)) { encl_delete(encl); TH_LOG("Failed to load the test enclave."); return false; @@ -284,7 +292,7 @@ TEST_F(enclave, unclobbered_vdso) struct encl_op_get_from_buf get_op; struct encl_op_put_to_buf put_op; - ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata)); + ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata, 0)); memset(&self->run, 0, sizeof(self->run)); self->run.tcs = self->encl.encl_base; @@ -357,7 +365,7 @@ TEST_F(enclave, unclobbered_vdso_oversubscribed) total_mem = get_total_epc_mem(); ASSERT_NE(total_mem, 0); - ASSERT_TRUE(setup_test_encl(total_mem, &self->encl, _metadata)); + ASSERT_TRUE(setup_test_encl(total_mem, &self->encl, _metadata, 0)); memset(&self->run, 0, sizeof(self->run)); self->run.tcs = self->encl.encl_base; @@ -401,7 +409,7 @@ TEST_F_TIMEOUT(enclave, unclobbered_vdso_oversubscribed_remove, 900) ASSERT_NE(total_mem, 0); TH_LOG("Creating an enclave with %lu bytes heap may take a while ...", total_mem); - ASSERT_TRUE(setup_test_encl(total_mem, &self->encl, _metadata)); + ASSERT_TRUE(setup_test_encl(total_mem, &self->encl, _metadata, 0)); /* * Hardware (SGX2) and kernel support is needed for this test. Start @@ -506,7 +514,7 @@ TEST_F(enclave, clobbered_vdso) struct encl_op_get_from_buf get_op; struct encl_op_put_to_buf put_op; - ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata)); + ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata, 0)); memset(&self->run, 0, sizeof(self->run)); self->run.tcs = self->encl.encl_base; @@ -542,7 +550,7 @@ TEST_F(enclave, clobbered_vdso_and_user_function) struct encl_op_get_from_buf get_op; struct encl_op_put_to_buf put_op; - ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata)); + ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata, 0)); memset(&self->run, 0, sizeof(self->run)); self->run.tcs = self->encl.encl_base; @@ -575,7 +583,7 @@ TEST_F(enclave, tcs_entry) { struct encl_op_header op; - ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata)); + ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata, 0)); memset(&self->run, 0, sizeof(self->run)); self->run.tcs = self->encl.encl_base; @@ -620,7 +628,7 @@ TEST_F(enclave, pte_permissions) unsigned long data_start; int ret; - ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata)); + ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata, 0)); memset(&self->run, 0, sizeof(self->run)); self->run.tcs = self->encl.encl_base; @@ -722,7 +730,7 @@ TEST_F(enclave, tcs_permissions) struct sgx_enclave_restrict_permissions ioc; int ret, errno_save; - ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata)); + ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata, 0)); memset(&self->run, 0, sizeof(self->run)); self->run.tcs = self->encl.encl_base; @@ -785,7 +793,7 @@ TEST_F(enclave, epcm_permissions) unsigned long data_start; int ret, errno_save; - ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata)); + ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata, 0)); memset(&self->run, 0, sizeof(self->run)); self->run.tcs = self->encl.encl_base; @@ -986,7 +994,7 @@ TEST_F(enclave, augment) if (!sgx2_supported()) SKIP(return, "SGX2 not supported"); - ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata)); + ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata, 0)); memset(&self->run, 0, sizeof(self->run)); self->run.tcs = self->encl.encl_base; @@ -1116,7 +1124,7 @@ TEST_F(enclave, augment_via_eaccept) if (!sgx2_supported()) SKIP(return, "SGX2 not supported"); - ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata)); + ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata, 0)); memset(&self->run, 0, sizeof(self->run)); self->run.tcs = self->encl.encl_base; @@ -1210,6 +1218,103 @@ TEST_F(enclave, augment_via_eaccept) munmap(addr, PAGE_SIZE); } +/* + * Test for the addition of large number of pages to an initialized enclave via + * a pre-emptive run of EACCEPT on every page to be added. + */ +TEST_F_TIMEOUT(enclave, augment_via_eaccept_long, TIMEOUT_LONG) +{ + struct encl_op_get_from_addr get_addr_op; + struct encl_op_put_to_addr put_addr_op; + struct encl_op_eaccept eaccept_op; + size_t total_size = 0; + unsigned long i; + void *addr; + + if (!sgx2_supported()) + SKIP(return, "SGX2 not supported"); + + ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata, + EDMM_SIZE_LONG)); + + memset(&self->run, 0, sizeof(self->run)); + self->run.tcs = self->encl.encl_base; + + for (i = 0; i < self->encl.nr_segments; i++) { + struct encl_segment *seg = &self->encl.segment_tbl[i]; + + total_size += seg->size; + } + + /* + * mmap() every page at end of existing enclave to be used for + * EDMM. + */ + addr = mmap((void *)self->encl.encl_base + total_size, EDMM_SIZE_LONG, + PROT_READ | PROT_WRITE | PROT_EXEC, MAP_SHARED | MAP_FIXED, + self->encl.fd, 0); + EXPECT_NE(addr, MAP_FAILED); + + self->run.exception_vector = 0; + self->run.exception_error_code = 0; + self->run.exception_addr = 0; + + /* + * Run EACCEPT on new page to trigger the #PF->EAUG->EACCEPT(again + * without a #PF). All should be transparent to userspace. + */ + eaccept_op.flags = SGX_SECINFO_R | SGX_SECINFO_W | SGX_SECINFO_REG | SGX_SECINFO_PENDING; + eaccept_op.ret = 0; + eaccept_op.header.type = ENCL_OP_EACCEPT; + + for (i = 0; i < EDMM_SIZE_LONG; i += 4096) { + eaccept_op.epc_addr = (uint64_t)(addr + i); + + EXPECT_EQ(ENCL_CALL(&eaccept_op, &self->run, true), 0); + if (self->run.exception_vector == 14 && + self->run.exception_error_code == 4 && + self->run.exception_addr == self->encl.encl_base) { + munmap(addr, EDMM_SIZE_LONG); + SKIP(return, "Kernel does not support adding pages to initialized enclave"); + } + + EXPECT_EQ(self->run.exception_vector, 0); + EXPECT_EQ(self->run.exception_error_code, 0); + EXPECT_EQ(self->run.exception_addr, 0); + ASSERT_EQ(eaccept_op.ret, 0); + ASSERT_EQ(self->run.function, EEXIT); + } + + put_addr_op.value = MAGIC; + put_addr_op.addr = (unsigned long)addr; + put_addr_op.header.type = ENCL_OP_PUT_TO_ADDRESS; + + EXPECT_EQ(ENCL_CALL(&put_addr_op, &self->run, true), 0); + + EXPECT_EEXIT(&self->run); + EXPECT_EQ(self->run.exception_vector, 0); + EXPECT_EQ(self->run.exception_error_code, 0); + EXPECT_EQ(self->run.exception_addr, 0); + + /* + * Read memory from newly added page that was just written to, + * confirming that data previously written (MAGIC) is present. + */ + get_addr_op.value = 0; + get_addr_op.addr = (unsigned long)addr; + get_addr_op.header.type = ENCL_OP_GET_FROM_ADDRESS; + + EXPECT_EQ(ENCL_CALL(&get_addr_op, &self->run, true), 0); + + EXPECT_EQ(get_addr_op.value, MAGIC); + EXPECT_EEXIT(&self->run); + EXPECT_EQ(self->run.exception_vector, 0); + EXPECT_EQ(self->run.exception_error_code, 0); + EXPECT_EQ(self->run.exception_addr, 0); + + munmap(addr, EDMM_SIZE_LONG); +} + /* * SGX2 page type modification test in two phases: * Phase 1: @@ -1238,7 +1343,7 @@ TEST_F(enclave, tcs_create) int ret, i; ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, - _metadata)); + _metadata, 0)); memset(&self->run, 0, sizeof(self->run)); self->run.tcs = self->encl.encl_base; @@ -1568,7 +1673,7 @@ TEST_F(enclave, remove_added_page_no_eaccept) unsigned long data_start; int ret, errno_save; - ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata)); + ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata, 0)); memset(&self->run, 0, sizeof(self->run)); self->run.tcs = self->encl.encl_base; @@ -1679,7 +1784,7 @@ TEST_F(enclave, remove_added_page_invalid_access) unsigned long data_start; int ret, errno_save; - ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata)); + ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata, 0)); memset(&self->run, 0, sizeof(self->run)); self->run.tcs = self->encl.encl_base; @@ -1794,7 +1899,7 @@ TEST_F(enclave, remove_added_page_invalid_access_after_eaccept) unsigned long data_start; int ret, errno_save; - ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata)); + ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata, 0)); memset(&self->run, 0, sizeof(self->run)); self->run.tcs = self->encl.encl_base; @@ -1918,7 +2023,7 @@ TEST_F(enclave, remove_untouched_page) unsigned long data_start; int ret, errno_save; - ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata)); + ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata, 0)); /* * Hardware (SGX2) and kernel support is needed for this test. Start diff --git a/tools/testing/selftests/sgx/main.h b/tools/testing/selftests/sgx/main.h index fc585be97e2f..fe5d39ac0e1e 100644 --- a/tools/testing/selftests/sgx/main.h +++ b/tools/testing/selftests/sgx/main.h @@ -35,7 +35,8 @@ extern unsigned char sign_key[]; extern unsigned char sign_key_end[]; void encl_delete(struct encl *ctx); -bool encl_load(const char *path, struct encl *encl, unsigned long heap_size); +bool encl_load(const char *path, struct encl *encl, unsigned long heap_size, + unsigned long edmm_size); bool encl_measure(struct encl *encl); bool encl_build(struct encl *encl); uint64_t encl_get_entry(struct encl *encl, const char *symbol); diff --git a/tools/testing/selftests/sgx/sigstruct.c b/tools/testing/selftests/sgx/sigstruct.c index a07896a46364..decd767434d5 100644 --- a/tools/testing/selftests/sgx/sigstruct.c +++ b/tools/testing/selftests/sgx/sigstruct.c @@ -349,7 +349,7 @@ bool encl_measure(struct encl *encl) if (!ctx) goto err; - if (!mrenclave_ecreate(ctx, encl->src_size)) + if (!mrenclave_ecreate(ctx, encl->encl_size)) goto err; for (i = 0; i < encl->nr_segments; i++) { -- 2.37.2

1 year, 8 months

2
7
0 0

[PATCH 6/6] selftests/sgx: Add a bpftrace script for tracking allocation errors

by Jarkko Sakkinen

Signed-off-by: Jarkko Sakkinen <jarkko(a)kernel.org> --- tools/testing/selftests/sgx/alloc-error.bt | 7 +++++++ 1 file changed, 7 insertions(+) create mode 100644 tools/testing/selftests/sgx/alloc-error.bt diff --git a/tools/testing/selftests/sgx/alloc-error.bt b/tools/testing/selftests/sgx/alloc-error.bt new file mode 100644 index 000000000000..9268d50dea29 --- /dev/null +++ b/tools/testing/selftests/sgx/alloc-error.bt @@ -0,0 +1,7 @@ +kr:sgx_alloc_epc_page /(uint64)retval >= (uint64)(-4095)/ { + printf("sgx_alloc_epc_page: retval=%d\n", (int64)retval); +} + +kr:sgx_encl_page_alloc /(uint64)retval >= (uint64)(-4095)/ { + printf("sgx_encl_page_alloc: retval=%d\n", (int64)retval); +} -- 2.37.2

1 year, 8 months

3
8
0 0

[PATCH v2] tools: Add new "test" taint to kernel-chktaint

by Joe Fradley

Commit c272612cb4a2 ("kunit: Taint the kernel when KUnit tests are run") added a new taint flag for when in-kernel tests run. This commit adds recognition of this new flag in kernel-chktaint. Reviewed-by: David Gow <davidgow(a)google.com> Signed-off-by: Joe Fradley <joefradley(a)google.com> --- Changes in v2: - based off of kselftest/kunit branch - Added David's Reviewed-by tag tools/debugging/kernel-chktaint | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/tools/debugging/kernel-chktaint b/tools/debugging/kernel-chktaint index f1af27ce9f20..279be06332be 100755 --- a/tools/debugging/kernel-chktaint +++ b/tools/debugging/kernel-chktaint @@ -187,6 +187,7 @@ else echo " * auxiliary taint, defined for and used by distros (#16)" fi + T=`expr $T / 2` if [ `expr $T % 2` -eq 0 ]; then addout " " @@ -195,6 +196,14 @@ else echo " * kernel was built with the struct randomization plugin (#17)" fi +T=`expr $T / 2` +if [ `expr $T % 2` -eq 0 ]; then + addout " " +else + addout "N" + echo " * an in-kernel test (such as a KUnit test) has been run (#18)" +fi + echo "For a more detailed explanation of the various taint flags see" echo " Documentation/admin-guide/tainted-kernels.rst in the Linux kernel sources" echo " or https://kernel.org/doc/html/latest/admin-guide/tainted-kernels.html" -- 2.37.1.595.g718a3a8f04-goog

1 year, 8 months

4
5
0 0

[PATCH v2 6/6] selftests/sgx: Add a bpftrace script for tracking allocation errors

by Jarkko Sakkinen

Signed-off-by: Jarkko Sakkinen <jarkko(a)kernel.org> --- v2: * Added comments. --- tools/testing/selftests/sgx/alloc-error.bt | 9 +++++++++ 1 file changed, 9 insertions(+) create mode 100644 tools/testing/selftests/sgx/alloc-error.bt diff --git a/tools/testing/selftests/sgx/alloc-error.bt b/tools/testing/selftests/sgx/alloc-error.bt new file mode 100644 index 000000000000..0cc8b2e41852 --- /dev/null +++ b/tools/testing/selftests/sgx/alloc-error.bt @@ -0,0 +1,9 @@ +/* EPC allocation */ +kr:sgx_alloc_epc_page /(uint64)retval >= (uint64)(-4095)/ { + printf("sgx_alloc_epc_page: retval=%d\n", (int64)retval); +} + +/* kzalloc for struct sgx_encl_page */ +kr:sgx_encl_page_alloc /(uint64)retval >= (uint64)(-4095)/ { + printf("sgx_encl_page_alloc: retval=%d\n", (int64)retval); +} -- 2.37.2

1 year, 8 months

2
2
0 0

[PATCH 5/6] selftests/sgx: retry the ioctls returned with EAGAIN

by Jarkko Sakkinen

From: Haitao Huang <haitao.huang(a)linux.intel.com> For EMODT and EREMOVE ioctls with a large range, kernel may not finish in one shot and return EAGAIN error code and count of bytes of EPC pages on that operations are finished successfully. Change the unclobbered_vdso_oversubscribed_remove test to rerun the ioctls in a loop, updating offset and length using the byte count returned in each iteration. Signed-off-by: Haitao Huang <haitao.huang(a)linux.intel.com> Tested-by: Jarkko Sakkinen <jarkko(a)kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko(a)kernel.org> --- tools/testing/selftests/sgx/main.c | 39 +++++++++++++++++++++++------- 1 file changed, 30 insertions(+), 9 deletions(-) diff --git a/tools/testing/selftests/sgx/main.c b/tools/testing/selftests/sgx/main.c index 867e98502120..3268d8b01b0b 100644 --- a/tools/testing/selftests/sgx/main.c +++ b/tools/testing/selftests/sgx/main.c @@ -399,7 +399,7 @@ TEST_F_TIMEOUT(enclave, unclobbered_vdso_oversubscribed_remove, 900) unsigned long total_mem; int ret, errno_save; unsigned long addr; - unsigned long i; + unsigned long i, count; /* * Create enclave with additional heap that is as big as all @@ -461,16 +461,27 @@ TEST_F_TIMEOUT(enclave, unclobbered_vdso_oversubscribed_remove, 900) modt_ioc.offset = heap->offset; modt_ioc.length = heap->size; modt_ioc.page_type = SGX_PAGE_TYPE_TRIM; - + count = 0; TH_LOG("Changing type of %zd bytes to trimmed may take a while ...", heap->size); - ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_MODIFY_TYPES, &modt_ioc); - errno_save = ret == -1 ? errno : 0; + do { + ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_MODIFY_TYPES, &modt_ioc); + errno_save = ret == -1 ? errno : 0; + if (errno_save == EAGAIN) { + count += modt_ioc.count; + modt_ioc.offset += modt_ioc.count; + modt_ioc.length -= modt_ioc.count; + modt_ioc.result = 0; + modt_ioc.count = 0; + } else + break; + } while (modt_ioc.length != 0); EXPECT_EQ(ret, 0); EXPECT_EQ(errno_save, 0); EXPECT_EQ(modt_ioc.result, 0); - EXPECT_EQ(modt_ioc.count, heap->size); + count += modt_ioc.count; + EXPECT_EQ(count, heap->size); /* EACCEPT all removed pages. */ addr = self->encl.encl_base + heap->offset; @@ -498,15 +509,25 @@ TEST_F_TIMEOUT(enclave, unclobbered_vdso_oversubscribed_remove, 900) remove_ioc.offset = heap->offset; remove_ioc.length = heap->size; - + count = 0; TH_LOG("Removing %zd bytes from enclave may take a while ...", heap->size); - ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_REMOVE_PAGES, &remove_ioc); - errno_save = ret == -1 ? errno : 0; + do { + ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_REMOVE_PAGES, &remove_ioc); + errno_save = ret == -1 ? errno : 0; + if (errno_save == EAGAIN) { + count += remove_ioc.count; + remove_ioc.offset += remove_ioc.count; + remove_ioc.length -= remove_ioc.count; + remove_ioc.count = 0; + } else + break; + } while (remove_ioc.length != 0); EXPECT_EQ(ret, 0); EXPECT_EQ(errno_save, 0); - EXPECT_EQ(remove_ioc.count, heap->size); + count += remove_ioc.count; + EXPECT_EQ(count, heap->size); } TEST_F(enclave, clobbered_vdso) -- 2.37.2

1 year, 8 months

3
6
0 0

[RFC PATCH v2 00/17] TDX KVM selftests

by Sagi Shahar

Hello, This is v2 of the patch series for TDX selftests. It is based on v5.19-rc8 and Intel's V8 of the TDX host patches which was proposed in https://lkml.org/lkml/2022/8/8/877 The tree can be found at https://github.com/googleprodkernel/linux-cc/tree/selftests Major changes vrom v1: - rebased to v5.19 - added helpers for success and failure reporting - added additional test cases --- TDX stands for Trust Domain Extensions which isolates VMs from the virtual-machine manager (VMM)/hypervisor and any other software on the platform. Intel has recently submitted a set of RFC patches for KVM support for TDX and more information can be found on the latest TDX Support Patches: https://lkml.org/lkml/2022/8/8/877 Due to the nature of the confidential computing environment that TDX provides, it is very difficult to verify/test the KVM support. TDX requires UEFI and the guest kernel to be enlightened which are all under development. We are working on a set of selftests to close this gap and be able to verify the KVM functionality to support TDX lifecycle and GHCI [1] interface. We are looking for any feedback on: - Patch series itself - Any suggestion on how we should approach testing TDX functionality. Does selftests seems reasonable or should we switch to using KVM unit tests. I would be happy to get some perspective on how KVM unit tests can help us more. - Any test case or scenario that we should add. - Anything else I have not thought of yet. Current patch series provide the following capabilities: - Provide helper functions to create a TD (Trusted Domain) using the KVM ioctls - Provide helper functions to create a guest image that can include any testing code - Provide helper functions and wrapper functions to write testing code using GHCI interface - Add a test case that verifies TDX life cycle - Add a test case that verifies TDX GHCI port IO TODOs: - Use existing function to create page tables dynamically (ie __virt_pg_map()) - Remove arbitrary defined magic numbers for data structure offsets - Add TDVMCALL for error reporting - Add additional test cases as some listed below - Add #VE handlers to help testing more complicated test cases --- Erdem Aktas (4): KVM: selftests: Add support for creating non-default type VMs KVM: selftest: Add helper functions to create TDX VMs KVM: selftest: Adding TDX life cycle test. KVM: selftest: Adding test case for TDX port IO Roger Wang (1): KVM: selftest: TDX: Add TDG.VP.INFO test Ryan Afranji (2): KVM: selftest: TDX: Verify the behavior when host consumes a TD private memory KVM: selftest: TDX: Add shared memory test Sagi Shahar (10): KVM: selftest: TDX: Add report_fatal_error test KVM: selftest: TDX: Add basic TDX CPUID test KVM: selftest: TDX: Add basic get_td_vmcall_info test KVM: selftest: TDX: Add TDX IO writes test KVM: selftest: TDX: Add TDX IO reads test KVM: selftest: TDX: Add TDX MSR read/write tests KVM: selftest: TDX: Add TDX HLT exit test KVM: selftest: TDX: Add TDX MMIO reads test KVM: selftest: TDX: Add TDX MMIO writes test KVM: selftest: TDX: Add TDX CPUID TDVMCALL test tools/testing/selftests/kvm/Makefile | 2 + .../selftests/kvm/include/kvm_util_base.h | 12 +- .../selftests/kvm/include/x86_64/processor.h | 1 + tools/testing/selftests/kvm/lib/kvm_util.c | 6 +- .../selftests/kvm/lib/x86_64/processor.c | 27 + tools/testing/selftests/kvm/lib/x86_64/tdx.h | 495 +++++ .../selftests/kvm/lib/x86_64/tdx_lib.c | 373 ++++ .../selftests/kvm/x86_64/tdx_vm_tests.c | 1666 +++++++++++++++++ 8 files changed, 2577 insertions(+), 5 deletions(-) create mode 100644 tools/testing/selftests/kvm/lib/x86_64/tdx.h create mode 100644 tools/testing/selftests/kvm/lib/x86_64/tdx_lib.c create mode 100644 tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c -- 2.37.2.789.g6183377224-goog

1 year, 8 months

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[PATCH] selftest: vm: remove orphaned references to local_config.{h,mk}

by Axel Rasmussen

Note: this commit is intended to apply to mm-unstable, the commit being fixed only exists in that branch for now. Commit b4efb234e53cc60ccdc855190be9f35918687412 ("Kselftests: remove support of libhugetlbfs from kselftests") removed the rule describing how to build local_config.{h,mk}, but it left two references to these files lingering around. The result is, none of the selftests could be built due to dependencies with no rule for how to build them. Signed-off-by: Axel Rasmussen <axelrasmussen(a)google.com> --- tools/testing/selftests/vm/Makefile | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile index b52f2cc51482..4ae879f70f4c 100644 --- a/tools/testing/selftests/vm/Makefile +++ b/tools/testing/selftests/vm/Makefile @@ -1,9 +1,7 @@ # SPDX-License-Identifier: GPL-2.0 # Makefile for vm selftests -LOCAL_HDRS += $(selfdir)/vm/local_config.h $(top_srcdir)/mm/gup_test.h - -include local_config.mk +LOCAL_HDRS += $(top_srcdir)/mm/gup_test.h uname_M := $(shell uname -m 2>/dev/null || echo not) MACHINE ?= $(shell echo $(uname_M) | sed -e 's/aarch64.*/arm64/' -e 's/ppc64.*/ppc64/') -- 2.37.2.789.g6183377224-goog

1 year, 8 months

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[PATCH v15 00/12] bpf: Add kfuncs for PKCS#7 signature verification

by Roberto Sassu

From: Roberto Sassu <roberto.sassu(a)huawei.com> One of the desirable features in security is the ability to restrict import of data to a given system based on data authenticity. If data import can be restricted, it would be possible to enforce a system-wide policy based on the signing keys the system owner trusts. This feature is widely used in the kernel. For example, if the restriction is enabled, kernel modules can be plugged in only if they are signed with a key whose public part is in the primary or secondary keyring. For eBPF, it can be useful as well. For example, it might be useful to authenticate data an eBPF program makes security decisions on. After a discussion in the eBPF mailing list, it was decided that the stated goal should be accomplished by introducing four new kfuncs: bpf_lookup_user_key() and bpf_lookup_system_key(), for retrieving a keyring with keys trusted for signature verification, respectively from its serial and from a pre-determined ID; bpf_key_put(), to release the reference obtained with the former two kfuncs, bpf_verify_pkcs7_signature(), for verifying PKCS#7 signatures. Other than the key serial, bpf_lookup_user_key() also accepts key lookup flags, that influence the behavior of the lookup. bpf_lookup_system_key() accepts pre-determined IDs defined in include/linux/verification.h. bpf_key_put() accepts the new bpf_key structure, introduced to tell whether the other structure member, a key pointer, is valid or not. The reason is that verify_pkcs7_signature() also accepts invalid pointers, set with the pre-determined ID, to select a system-defined keyring. key_put() must be called only for valid key pointers. Since the two key lookup functions allocate memory and one increments a key reference count, they must be used in conjunction with bpf_key_put(). The latter must be called only if the lookup functions returned a non-NULL pointer. The verifier denies the execution of eBPF programs that don't respect this rule. The two key lookup functions should be used in alternative, depending on the use case. While bpf_lookup_user_key() provides great flexibility, it seems suboptimal in terms of security guarantees, as even if the eBPF program is assumed to be trusted, the serial used to obtain the key pointer might come from untrusted user space not choosing one that the system administrator approves to enforce a mandatory policy. bpf_lookup_system_key() instead provides much stronger guarantees, especially if the pre-determined ID is not passed by user space but is hardcoded in the eBPF program, and that program is signed. In this case, bpf_verify_pkcs7_signature() will always perform signature verification with a key that the system administrator approves, i.e. the primary, secondary or platform keyring. Nevertheless, key permission checks need to be done accurately. Since bpf_lookup_user_key() cannot determine how a key will be used by other kfuncs, it has to defer the permission check to the actual kfunc using the key. It does it by calling lookup_user_key() with KEY_DEFER_PERM_CHECK as needed permission. Later, bpf_verify_pkcs7_signature(), if called, completes the permission check by calling key_validate(). It does not need to call key_task_permission() with permission KEY_NEED_SEARCH, as it is already done elsewhere by the key subsystem. Future kfuncs using the bpf_key structure need to implement the proper checks as well. Finally, the last kfunc, bpf_verify_pkcs7_signature(), accepts the data and signature to verify as eBPF dynamic pointers, to minimize the number of kfunc parameters, and the keyring with keys for signature verification as a bpf_key structure, returned by one of the two key lookup functions. bpf_lookup_user_key() and bpf_verify_pkcs7_signature() can be called only from sleepable programs, because of memory allocation and crypto operations. For example, the lsm.s/bpf attach point is suitable, fexit/array_map_update_elem is not. The correctness of implementation of the new kfuncs and of their usage is checked with the introduced tests. The patch set includes a patch from another author (dependency) for sake of completeness. It is organized as follows. Patch 1 from KP Singh allows kfuncs to be used by LSM programs. Patch 2 splits is_dynptr_reg_valid_init() and introduces is_dynptr_type_expected(), to know more precisely the cause of a negative result of a dynamic pointer check. Patch 3 allows dynamic pointers to be used as kfunc parameters. Patch 4 exports bpf_dynptr_get_size(), to obtain the real size of data carried by a dynamic pointer. Patch 5 makes available for new eBPF kfuncs and programs some key-related definitions. Patch 6 introduces the bpf_lookup_*_key() and bpf_key_put() kfuncs. Patch 7 introduces the bpf_verify_pkcs7_signature() kfunc. Patch 8 changes the testing kernel configuration to compile everything as built-in. Finally, patches 9-12 introduce the tests. Changelog v14: - Explain that is_dynptr_type_expected() will be useful also for BTF (suggested by Joanne) - Rename KEY_LOOKUP_FLAGS_ALL to KEY_LOOKUP_ALL (suggested by Jarkko) - Swap declaration of spi and dynptr_type in is_dynptr_type_expected() (suggested by Joanne) - Reimplement kfunc dynptr tests with a regular eBPF program instead of executing them with test_verifier (suggested by Joanne) - Make key lookup flags as enum so that they are automatically exported through BTF (suggested by Alexei) v13: - Split is_dynptr_reg_valid_init() and introduce is_dynptr_type_expected() to see if the dynamic pointer type passed as argument to a kfunc is supported (suggested by Kumar) - Add forward declaration of struct key in include/linux/bpf.h (suggested by Song) - Declare mask for key lookup flags, remove key_lookup_flags_check() (suggested by Jarkko and KP) - Allow only certain dynamic pointer types (currently, local) to be passed as argument to kfuncs (suggested by Kumar) - For each dynamic pointer parameter in kfunc, additionally check if the passed pointer is to the stack (suggested by Kumar) - Split the validity/initialization and dynamic pointer type check also in the verifier, and adjust the expected error message in the test (a test for an unexpected dynptr type passed to a helper cannot be added due to missing suitable helpers, but this case has been tested manually) - Add verifier tests to check the dynamic pointers passed as argument to kfuncs (suggested by Kumar) v12: - Put lookup_key and verify_pkcs7_sig tests in deny list for s390x (JIT does not support calling kernel function) v11: - Move stringify_struct() macro to include/linux/btf.h (suggested by Daniel) - Change kernel configuration options in tools/testing/selftests/bpf/config* from =m to =y v10: - Introduce key_lookup_flags_check() and system_keyring_id_check() inline functions to check parameters (suggested by KP) - Fix descriptions and comment of key-related kfuncs (suggested by KP) - Register kfunc set only once (suggested by Alexei) - Move needed kernel options to the architecture-independent configuration for testing v9: - Drop patch to introduce KF_SLEEPABLE kfunc flag (already merged) - Rename valid_ptr member of bpf_key to has_ref (suggested by Daniel) - Check dynamic pointers in kfunc definition with bpf_dynptr_kern struct definition instead of string, to detect structure renames (suggested by Daniel) - Explicitly say that we permit initialized dynamic pointers in kfunc definition (suggested by Daniel) - Remove noinline __weak from kfuncs definition (reported by Daniel) - Simplify key lookup flags check in bpf_lookup_user_key() (suggested by Daniel) - Explain the reason for deferring key permission check (suggested by Daniel) - Allocate memory with GFP_ATOMIC in bpf_lookup_system_key(), and remove KF_SLEEPABLE kfunc flag from kfunc declaration (suggested by Daniel) - Define only one kfunc set and remove the loop for registration (suggested by Alexei) v8: - Define the new bpf_key structure to carry the key pointer and whether that pointer is valid or not (suggested by Daniel) - Drop patch to mark a kfunc parameter with the __maybe_null suffix - Improve documentation of kfuncs - Introduce bpf_lookup_system_key() to obtain a key pointer suitable for verify_pkcs7_signature() (suggested by Daniel) - Use the new kfunc registration API - Drop patch to test the __maybe_null suffix - Add tests for bpf_lookup_system_key() v7: - Add support for using dynamic and NULL pointers in kfunc (suggested by Alexei) - Add new kfunc-related tests v6: - Switch back to key lookup helpers + signature verification (until v5), and defer permission check from bpf_lookup_user_key() to bpf_verify_pkcs7_signature() - Add additional key lookup test to illustrate the usage of the KEY_LOOKUP_CREATE flag and validate the flags (suggested by Daniel) - Make description of flags of bpf_lookup_user_key() more user-friendly (suggested by Daniel) - Fix validation of flags parameter in bpf_lookup_user_key() (reported by Daniel) - Rename bpf_verify_pkcs7_signature() keyring-related parameters to user_keyring and system_keyring to make their purpose more clear - Accept keyring-related parameters of bpf_verify_pkcs7_signature() as alternatives (suggested by KP) - Replace unsigned long type with u64 in helper declaration (suggested by Daniel) - Extend the bpf_verify_pkcs7_signature() test by calling the helper without data, by ensuring that the helper enforces the keyring-related parameters as alternatives, by ensuring that the helper rejects inaccessible and expired keyrings, and by checking all system keyrings - Move bpf_lookup_user_key() and bpf_key_put() usage tests to ref_tracking.c (suggested by John) - Call bpf_lookup_user_key() and bpf_key_put() only in sleepable programs v5: - Move KEY_LOOKUP_ to include/linux/key.h for validation of bpf_verify_pkcs7_signature() parameter - Remove bpf_lookup_user_key() and bpf_key_put() helpers, and the corresponding tests - Replace struct key parameter of bpf_verify_pkcs7_signature() with the keyring serial and lookup flags - Call lookup_user_key() and key_put() in bpf_verify_pkcs7_signature() code, to ensure that the retrieved key is used according to the permission requested at lookup time - Clarified keyring precedence in the description of bpf_verify_pkcs7_signature() (suggested by John) - Remove newline in the second argument of ASSERT_ - Fix helper prototype regular expression in bpf_doc.py v4: - Remove bpf_request_key_by_id(), don't return an invalid pointer that other helpers can use - Pass the keyring ID (without ULONG_MAX, suggested by Alexei) to bpf_verify_pkcs7_signature() - Introduce bpf_lookup_user_key() and bpf_key_put() helpers (suggested by Alexei) - Add lookup_key_norelease test, to ensure that the verifier blocks eBPF programs which don't decrement the key reference count - Parse raw PKCS#7 signature instead of module-style signature in the verify_pkcs7_signature test (suggested by Alexei) - Parse kernel module in user space and pass raw PKCS#7 signature to the eBPF program for signature verification v3: - Rename bpf_verify_signature() back to bpf_verify_pkcs7_signature() to avoid managing different parameters for each signature verification function in one helper (suggested by Daniel) - Use dynamic pointers and export bpf_dynptr_get_size() (suggested by Alexei) - Introduce bpf_request_key_by_id() to give more flexibility to the caller of bpf_verify_pkcs7_signature() to retrieve the appropriate keyring (suggested by Alexei) - Fix test by reordering the gcc command line, always compile sign-file - Improve helper support check mechanism in the test v2: - Rename bpf_verify_pkcs7_signature() to a more generic bpf_verify_signature() and pass the signature type (suggested by KP) - Move the helper and prototype declaration under #ifdef so that user space can probe for support for the helper (suggested by Daniel) - Describe better the keyring types (suggested by Daniel) - Include linux/bpf.h instead of vmlinux.h to avoid implicit or redeclaration - Make the test selfcontained (suggested by Alexei) v1: - Don't define new map flag but introduce simple wrapper of verify_pkcs7_signature() (suggested by Alexei and KP) KP Singh (1): bpf: Allow kfuncs to be used in LSM programs Roberto Sassu (11): bpf: Move dynptr type check to is_dynptr_type_expected() btf: Allow dynamic pointer parameters in kfuncs bpf: Export bpf_dynptr_get_size() KEYS: Move KEY_LOOKUP_ to include/linux/key.h and define KEY_LOOKUP_ALL bpf: Add bpf_lookup_*_key() and bpf_key_put() kfuncs bpf: Add bpf_verify_pkcs7_signature() kfunc selftests/bpf: Compile kernel with everything as built-in selftests/bpf: Add verifier tests for bpf_lookup_*_key() and bpf_key_put() selftests/bpf: Add additional tests for bpf_lookup_*_key() selftests/bpf: Add test for bpf_verify_pkcs7_signature() kfunc selftests/bpf: Add tests for dynamic pointers parameters in kfuncs include/linux/bpf.h | 9 + include/linux/bpf_verifier.h | 5 + include/linux/btf.h | 9 + include/linux/key.h | 6 + include/linux/verification.h | 8 + kernel/bpf/btf.c | 34 ++ kernel/bpf/helpers.c | 2 +- kernel/bpf/verifier.c | 35 +- kernel/trace/bpf_trace.c | 180 ++++++++ security/keys/internal.h | 2 - tools/testing/selftests/bpf/DENYLIST.s390x | 2 + tools/testing/selftests/bpf/Makefile | 14 +- tools/testing/selftests/bpf/config | 32 +- tools/testing/selftests/bpf/config.x86_64 | 7 +- .../testing/selftests/bpf/prog_tests/dynptr.c | 2 +- .../bpf/prog_tests/kfunc_dynptr_param.c | 102 +++++ .../selftests/bpf/prog_tests/lookup_key.c | 112 +++++ .../bpf/prog_tests/verify_pkcs7_sig.c | 399 ++++++++++++++++++ .../bpf/progs/test_kfunc_dynptr_param.c | 57 +++ .../selftests/bpf/progs/test_lookup_key.c | 46 ++ .../bpf/progs/test_verify_pkcs7_sig.c | 100 +++++ tools/testing/selftests/bpf/test_verifier.c | 3 +- .../selftests/bpf/verifier/ref_tracking.c | 139 ++++++ .../testing/selftests/bpf/verify_sig_setup.sh | 104 +++++ 24 files changed, 1374 insertions(+), 35 deletions(-) create mode 100644 tools/testing/selftests/bpf/prog_tests/kfunc_dynptr_param.c create mode 100644 tools/testing/selftests/bpf/prog_tests/lookup_key.c create mode 100644 tools/testing/selftests/bpf/prog_tests/verify_pkcs7_sig.c create mode 100644 tools/testing/selftests/bpf/progs/test_kfunc_dynptr_param.c create mode 100644 tools/testing/selftests/bpf/progs/test_lookup_key.c create mode 100644 tools/testing/selftests/bpf/progs/test_verify_pkcs7_sig.c create mode 100755 tools/testing/selftests/bpf/verify_sig_setup.sh -- 2.25.1

1 year, 8 months

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Linux-kselftest-mirror August 2022