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[PATCH v16 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 v15: - Add kfunc_dynptr_param test to deny list for s390x 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 | 3 + 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 | 103 +++++ .../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, 1376 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

2 years, 9 months

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[PATCH] KVM: selftests: Make rseq compatible with versions prior to glibc-2.30

by Liam Merwick

The fix for commit e923b0537d28 ("KVM: selftests: Fix target thread to be migrated in rseq_test") added a call to gettid() which was only added to glibc-2.30 and fails to compile with older glibc versions. rseq_test.c: In function 'main': rseq_test.c:230:33: warning: implicit declaration of function 'gettid'; did you mean 'getgid'? [-Wimplicit-function-declaration] (void *)(unsigned long)gettid()); ^~~~~~ getgid Switch the call to syscall(SYS_gettid) which was the original advice in the gettid(2) NOTES section and which works with both new and older glibc versions. Fixes: e923b0537d28 ("KVM: selftests: Fix target thread to be migrated in rseq_test") Cc: stable(a)vger.kernel.org # v5.15 Signed-off-by: Liam Merwick <liam.merwick(a)oracle.com> --- Verified with glibc-2.28 and glibc-2.34 and ensured test case from e923b0537d28 still passes. tools/testing/selftests/kvm/rseq_test.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/kvm/rseq_test.c b/tools/testing/selftests/kvm/rseq_test.c index fac248a43666..6f88da7e60be 100644 --- a/tools/testing/selftests/kvm/rseq_test.c +++ b/tools/testing/selftests/kvm/rseq_test.c @@ -227,7 +227,7 @@ int main(int argc, char *argv[]) ucall_init(vm, NULL); pthread_create(&migration_thread, NULL, migration_worker, - (void *)(unsigned long)gettid()); + (void *)(unsigned long)syscall(SYS_gettid)); for (i = 0; !done; i++) { vcpu_run(vcpu); -- 2.31.1

2 years, 9 months

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ATTENTION/PROPOSAL

by LUMAR CASEY

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2 years, 9 months

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Re: [fortify] 728833277d: WARNING:at_net/netlink/af_netlink.c:#netlink_ack

by Gustavo A. R. Silva

On Wed, Sep 07, 2022 at 01:42:16PM +0800, kernel test robot wrote: Hi! > > Hi Kees Cook, > > the patch "[PATCH 1/2] fortify: Add run-time WARN for cross-field memcpy()" > raises a persistent WARNING as below report in our tests. > > according to commit message, we understand this is kind of expected. but > we don't have enough knowledge if it reveals a real issue in kernel source > code and what the next step could be. > > so we still report FYI. > > if you think it's unnecessary for us to make out this kind of report, please > let us know. we will consider how to refine our report rules. Thanks a lot! > > below is the full report. It seems that the idea is to continue reporting these warnings, as they help us identify the places that need to be audited and determine how to refactor the code (in case it's a false positive), or how to properly fix it (in case it's an actual bug). In this case, it seems that the issue was already addressed by this patch: https://lore.kernel.org/linux-hardening/20220903043749.3102675-1-keescook@c… Thanks -- Gustavo

2 years, 9 months

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3% Rate

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2 years, 9 months

1
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Re: [PATCH V5 15/31] x86/sgx: Support restricting of enclave page permissions

by zhubojun

Hi, Reinette, thanks for your great contribution for EDMM Linux kernel patch. I am trying to follow the newest patch now, and I have some questions on it. It seems that `sgx_enclave_restrict_permissions()` is able to do permission restrictions for multiple enclave’s pages. After driver invokes ENCLS[EMODPR] to restrict the page’s permission, it should then invoke ENCLS[ETRACK] and send IPIs to ensure stale TLB entries have been flushed. Only in this way, ENCLU[EACCEPT] inside enclave can only succeed. Current implementation invokes `sgx_enclave_etrack(encl)` after every `__emodpr(…)` in the for loop. My question is: Can we move the `sgx_enclave_etrack(encl)` out of the for loop? After doing so, `sgx_enclave_etrack(encl)` is invoked **one** time for multiple enclave pages’ permission restriction, instead of N times (N = `modp -> length / PAGE_SIZE`). We may gain some performance optimization from it. Please correct my if my understanding is incorrect. Looking forward to your reply and Thanks for your time! BR, Bojun

2 years, 9 months

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[PATCH v3 0/3] arm64/sve: Document our actual SVE syscall ABI

by Mark Brown

Currently our SVE syscall ABI documentation does not reflect the actual implemented ABI, it says that register state not shared with FPSIMD becomes undefined on syscall when in reality we always clear it. Since changing this would cause a change in the observed kernel behaviour there is a substantial desire to avoid taking advantage of the documented ABI so instead let's document what we actually do so it's clear that it is in reality an ABI. There has been some pushback on tightening the documentation in the past but it is hard to see who that helps, it makes the implementation decisions less clear and makes it harder for people to discover and make use of the actual ABI. The main practical concern is that qemu's user mode does not currently flush the registers. v3: - Rebase onto v6.0-rc3. v2: - Rebase onto v6.0-rc1. Mark Brown (3): kselftest/arm64: Correct buffer allocation for SVE Z registers arm64/sve: Document our actual ABI for clearing registers on syscall kselftest/arm64: Enforce actual ABI for SVE syscalls Documentation/arm64/sve.rst | 2 +- .../testing/selftests/arm64/abi/syscall-abi.c | 61 ++++++++++++------- 2 files changed, 41 insertions(+), 22 deletions(-) base-commit: b90cb1053190353cc30f0fef0ef1f378ccc063c5 -- 2.30.2

2 years, 10 months

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[PATCH v2] kselftest/arm64: Add simple hwcap validation

by Mark Brown

Add some trivial hwcap validation which checks that /proc/cpuinfo and AT_HWCAP agree with each other and can verify that for extensions that can generate a SIGILL due to adding new instructions one appears or doesn't appear as expected. I've added SVE and SME, other capabilities can be added later if this gets merged. This isn't super exciting but on the other hand took very little time to write and should be handy when verifying that you wired up AT_HWCAP properly. Signed-off-by: Mark Brown <broonie(a)kernel.org> --- tools/testing/selftests/arm64/abi/.gitignore | 1 + tools/testing/selftests/arm64/abi/Makefile | 2 +- tools/testing/selftests/arm64/abi/hwcap.c | 188 +++++++++++++++++++ 3 files changed, 190 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/arm64/abi/hwcap.c diff --git a/tools/testing/selftests/arm64/abi/.gitignore b/tools/testing/selftests/arm64/abi/.gitignore index b9e54417250d..c31d34d48a30 100644 --- a/tools/testing/selftests/arm64/abi/.gitignore +++ b/tools/testing/selftests/arm64/abi/.gitignore @@ -1,2 +1,3 @@ +hwcap syscall-abi tpidr2 diff --git a/tools/testing/selftests/arm64/abi/Makefile b/tools/testing/selftests/arm64/abi/Makefile index c8d7f2495eb2..e60752eb8334 100644 --- a/tools/testing/selftests/arm64/abi/Makefile +++ b/tools/testing/selftests/arm64/abi/Makefile @@ -1,7 +1,7 @@ # SPDX-License-Identifier: GPL-2.0 # Copyright (C) 2021 ARM Limited -TEST_GEN_PROGS := syscall-abi tpidr2 +TEST_GEN_PROGS := hwcap syscall-abi tpidr2 include ../../lib.mk diff --git a/tools/testing/selftests/arm64/abi/hwcap.c b/tools/testing/selftests/arm64/abi/hwcap.c new file mode 100644 index 000000000000..8b5c646cea63 --- /dev/null +++ b/tools/testing/selftests/arm64/abi/hwcap.c @@ -0,0 +1,188 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2022 ARM Limited. + */ + +#include <errno.h> +#include <signal.h> +#include <stdbool.h> +#include <stddef.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <sys/auxv.h> +#include <sys/prctl.h> +#include <asm/hwcap.h> +#include <asm/sigcontext.h> +#include <asm/unistd.h> + +#include "../../kselftest.h" + +#define TESTS_PER_HWCAP 2 + +/* + * Function expected to generate SIGILL when the feature is not + * supported and return when it is supported. If SIGILL is generated + * then the handler must be able to skip over the instruction safely. + * + * Note that it is expected that for many architecture extensions + * there are no specific traps due to no architecture state being + * added so we may not fault if running on a kernel which doesn't know + * to add the hwcap. + */ +typedef void (*sigill_fn)(void); + +static void sme_sigill(void) +{ + /* RDSVL x0, #0 */ + asm volatile(".inst 0x04bf5800" : : : "x0"); +} + +static void sve_sigill(void) +{ + /* RDVL x0, #0 */ + asm volatile(".inst 0x04bf5000" : : : "x0"); +} + +static const struct hwcap_data { + const char *name; + unsigned long at_hwcap; + unsigned long hwcap_bit; + const char *cpuinfo; + sigill_fn sigill_fn; + bool sigill_reliable; +} hwcaps[] = { + { + .name = "SME", + .at_hwcap = AT_HWCAP2, + .hwcap_bit = HWCAP2_SME, + .cpuinfo = "sme", + .sigill_fn = sme_sigill, + .sigill_reliable = true, + }, + { + .name = "SVE", + .at_hwcap = AT_HWCAP, + .hwcap_bit = HWCAP_SVE, + .cpuinfo = "sve", + .sigill_fn = sve_sigill, + .sigill_reliable = true, + }, +}; + +static bool seen_sigill; + +static void handle_sigill(int sig, siginfo_t *info, void *context) +{ + ucontext_t *uc = context; + + seen_sigill = true; + + /* Skip over the offending instruction */ + uc->uc_mcontext.pc += 4; +} + +bool cpuinfo_present(const char *name) +{ + FILE *f; + char buf[2048], name_space[30], name_newline[30]; + char *s; + + /* + * The feature should appear with a leading space and either a + * trailing space or a newline. + */ + snprintf(name_space, sizeof(name_space), " %s ", name); + snprintf(name_newline, sizeof(name_newline), " %s\n", name); + + f = fopen("/proc/cpuinfo", "r"); + if (!f) { + ksft_print_msg("Failed to open /proc/cpuinfo\n"); + return false; + } + + while (fgets(buf, sizeof(buf), f)) { + /* Features: line? */ + if (strncmp(buf, "Features\t:", strlen("Features\t:")) != 0) + continue; + + /* All CPUs should be symmetric, don't read any more */ + fclose(f); + + s = strstr(buf, name_space); + if (s) + return true; + s = strstr(buf, name_newline); + if (s) + return true; + + return false; + } + + ksft_print_msg("Failed to find Features in /proc/cpuinfo\n"); + fclose(f); + return false; +} + +int main(void) +{ + const struct hwcap_data *hwcap; + int i, ret; + bool have_cpuinfo, have_hwcap; + struct sigaction sa; + + ksft_print_header(); + ksft_set_plan(ARRAY_SIZE(hwcaps) * TESTS_PER_HWCAP); + + memset(&sa, 0, sizeof(sa)); + sa.sa_sigaction = handle_sigill; + sa.sa_flags = SA_RESTART | SA_SIGINFO; + sigemptyset(&sa.sa_mask); + ret = sigaction(SIGILL, &sa, NULL); + if (ret < 0) + ksft_exit_fail_msg("Failed to install SIGILL handler: %s (%d)\n", + strerror(errno), errno); + + for (i = 0; i < ARRAY_SIZE(hwcaps); i++) { + hwcap = &hwcaps[i]; + + have_hwcap = getauxval(hwcaps->at_hwcap) & hwcap->hwcap_bit; + have_cpuinfo = cpuinfo_present(hwcap->cpuinfo); + + if (have_hwcap) + ksft_print_msg("%s present", hwcap->name); + + ksft_test_result(have_hwcap == have_cpuinfo, + "cpuinfo_match_%s\n", hwcap->name); + + if (hwcap->sigill_fn) { + seen_sigill = false; + hwcap->sigill_fn(); + + if (have_hwcap) { + /* Should be able to use the extension */ + ksft_test_result(!seen_sigill, "sigill_%s\n", + hwcap->name); + } else if (hwcap->sigill_reliable) { + /* Guaranteed a SIGILL */ + ksft_test_result(seen_sigill, "sigill_%s\n", + hwcap->name); + } else { + /* Missing SIGILL might be fine */ + ksft_print_msg("SIGILL %sreported for %s\n", + seen_sigill ? "" : "not ", + hwcap->name); + ksft_test_result_skip("sigill_%s\n", + hwcap->name); + } + } else { + ksft_test_result_skip("sigill_%s\n", + hwcap->name); + } + } + + ksft_print_cnts(); + + return 0; +} base-commit: b90cb1053190353cc30f0fef0ef1f378ccc063c5 -- 2.30.2

2 years, 10 months

2
1
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[PATCH v2 0/4] kselftest/arm64: Floating point stress test harness

by Mark Brown

This series has a few small enhancements for the existing standalone floating point stress tests and then builds on those with a kselftest integrated program which gives those a very quick spin from within kselftest, as well as having an option to set a custom timeout to allow for use with longer soak testing. This makes it much easier to get thorough testing of the floating point state management logic, rather than requiring custom setup for coverage of the various vector lengths in the system as is needed at present. It might be nice in future to extend this to attach to some or all of the test programs with ptrace and read/write their registers as another means of potentially triggering race conditions or corruption but that's definitely another step. v2: - Rebase onto v6.0-rc3. - Announce the results of enumeration before we start everything. Mark Brown (4): kselftest/arm64: Always encourage preemption for za-test kselftest/arm64: Count SIGUSR2 deliveries in FP stress tests kselftest/arm64: Install signal handlers before output in FP stress tests kselftest/arm64: kselftest harness for FP stress tests tools/testing/selftests/arm64/fp/.gitignore | 1 + tools/testing/selftests/arm64/fp/Makefile | 5 +- .../testing/selftests/arm64/fp/asm-offsets.h | 1 + tools/testing/selftests/arm64/fp/fp-stress.c | 535 ++++++++++++++++++ .../testing/selftests/arm64/fp/fpsimd-test.S | 51 +- tools/testing/selftests/arm64/fp/sve-test.S | 51 +- tools/testing/selftests/arm64/fp/za-test.S | 58 +- 7 files changed, 641 insertions(+), 61 deletions(-) create mode 100644 tools/testing/selftests/arm64/fp/fp-stress.c base-commit: b90cb1053190353cc30f0fef0ef1f378ccc063c5 -- 2.30.2

2 years, 10 months

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[PATCH v2 0/2] kselftest/arm64: Small improvements to ZA signal handling coverag

by Mark Brown

These patches improve the coverage of ZA signal contexts a bit, adding some validation that the actual data is correct and covering the case where ZA is not enabled. v2: - Rebase onto v6.0-rc3. Mark Brown (2): kselftest/arm64: Tighten up validation of ZA signal context kselftest/arm64: Add a test for signal frames with ZA disabled .../arm64/signal/testcases/za_no_regs.c | 119 ++++++++++++++++++ .../arm64/signal/testcases/za_regs.c | 16 ++- 2 files changed, 134 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/arm64/signal/testcases/za_no_regs.c base-commit: b90cb1053190353cc30f0fef0ef1f378ccc063c5 -- 2.30.2

2 years, 10 months

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