This test checks that the memory tag is present after mte allocation and the memory is accessible with those tags. This testcase verifies all sync, async and none mte error reporting mode. The allocated mte buffers are verified for Allocated range (no error expected while accessing buffer), Underflow range, and Overflow range.

Different test scenarios covered here are, * Verify that mte memory are accessible at byte/block level. * Force underflow and overflow to occur and check the data consistency. * Check to/from between tagged and untagged memory. * Check that initial allocated memory to have 0 tag.

This change also creates the necessary infrastructure to add mte test cases. MTE kselftests can use the several utility functions provided here to add wide variety of mte test scenarios.

GCC compiler need flag '-march=armv8.5-a+memtag' so those flags are verified before compilation.

The mte testcases can be launched with kselftest framework as,

make TARGETS=arm64 ARM64_SUBTARGETS=mte kselftest

or compiled as,

make -C tools/testing/selftests TARGETS=arm64 ARM64_SUBTARGETS=mte CC='compiler'

Cc: Shuah Khan shuah@kernel.org Cc: Catalin Marinas catalin.marinas@arm.com Cc: Will Deacon will@kernel.org Co-developed-by: Gabor Kertesz gabor.kertesz@arm.com Signed-off-by: Gabor Kertesz gabor.kertesz@arm.com Signed-off-by: Amit Daniel Kachhap amit.kachhap@arm.com --- Changes in v2: * Redefined MTE kernel header definitions to decouple kselftest compilations. * Removed gmi masking instructions in mte_insert_random_tag assembly function. This simplifies the tag inclusion mask test with only GCR mask register used. * Now use /dev/shm/* to hold temporary tmpfs files. * Few Code and comment clean-ups.

tools/testing/selftests/arm64/Makefile | 2 +- tools/testing/selftests/arm64/mte/.gitignore | 1 + tools/testing/selftests/arm64/mte/Makefile | 29 ++ .../selftests/arm64/mte/check_buffer_fill.c | 475 ++++++++++++++++++ .../selftests/arm64/mte/mte_common_util.c | 341 +++++++++++++ .../selftests/arm64/mte/mte_common_util.h | 117 +++++ tools/testing/selftests/arm64/mte/mte_def.h | 60 +++ .../testing/selftests/arm64/mte/mte_helper.S | 114 +++++ 8 files changed, 1138 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/arm64/mte/.gitignore create mode 100644 tools/testing/selftests/arm64/mte/Makefile create mode 100644 tools/testing/selftests/arm64/mte/check_buffer_fill.c create mode 100644 tools/testing/selftests/arm64/mte/mte_common_util.c create mode 100644 tools/testing/selftests/arm64/mte/mte_common_util.h create mode 100644 tools/testing/selftests/arm64/mte/mte_def.h create mode 100644 tools/testing/selftests/arm64/mte/mte_helper.S

diff --git a/tools/testing/selftests/arm64/Makefile b/tools/testing/selftests/arm64/Makefile index 93b567d23c8b..3723d9dea11a 100644 --- a/tools/testing/selftests/arm64/Makefile +++ b/tools/testing/selftests/arm64/Makefile @@ -4,7 +4,7 @@ ARCH ?= $(shell uname -m 2>/dev/null || echo not)

ifneq (,$(filter $(ARCH),aarch64 arm64)) -ARM64_SUBTARGETS ?= tags signal +ARM64_SUBTARGETS ?= tags signal mte else ARM64_SUBTARGETS := endif diff --git a/tools/testing/selftests/arm64/mte/.gitignore b/tools/testing/selftests/arm64/mte/.gitignore new file mode 100644 index 000000000000..3f8c1f6c82b9 --- /dev/null +++ b/tools/testing/selftests/arm64/mte/.gitignore @@ -0,0 +1 @@ +check_buffer_fill diff --git a/tools/testing/selftests/arm64/mte/Makefile b/tools/testing/selftests/arm64/mte/Makefile new file mode 100644 index 000000000000..2480226dfe57 --- /dev/null +++ b/tools/testing/selftests/arm64/mte/Makefile @@ -0,0 +1,29 @@ +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2020 ARM Limited + +CFLAGS += -std=gnu99 -I. +SRCS := $(filter-out mte_common_util.c,$(wildcard *.c)) +PROGS := $(patsubst %.c,%,$(SRCS)) + +#Add mte compiler option +ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep gcc),) +CFLAGS += -march=armv8.5-a+memtag +endif + +#check if the compiler works well +mte_cc_support := $(shell if ($(CC) $(CFLAGS) -E -x c /dev/null -o /dev/null 2>&1) then echo "1"; fi) + +ifeq ($(mte_cc_support),1) +# Generated binaries to be installed by top KSFT script +TEST_GEN_PROGS := $(PROGS) + +# Get Kernel headers installed and use them. +KSFT_KHDR_INSTALL := 1 +endif + +# Include KSFT lib.mk. +include ../../lib.mk + +ifeq ($(mte_cc_support),1) +$(TEST_GEN_PROGS): mte_common_util.c mte_common_util.h mte_helper.S +endif diff --git a/tools/testing/selftests/arm64/mte/check_buffer_fill.c b/tools/testing/selftests/arm64/mte/check_buffer_fill.c new file mode 100644 index 000000000000..242635d79035 --- /dev/null +++ b/tools/testing/selftests/arm64/mte/check_buffer_fill.c @@ -0,0 +1,475 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2020 ARM Limited + +#define _GNU_SOURCE + +#include <stddef.h> +#include <stdio.h> +#include <string.h> + +#include "kselftest.h" +#include "mte_common_util.h" +#include "mte_def.h" + +#define OVERFLOW_RANGE MT_GRANULE_SIZE + +static int sizes[] = { + 1, 555, 1033, MT_GRANULE_SIZE - 1, MT_GRANULE_SIZE, + /* page size - 1*/ 0, /* page_size */ 0, /* page size + 1 */ 0 +}; + +enum mte_block_test_alloc { + UNTAGGED_TAGGED, + TAGGED_UNTAGGED, + TAGGED_TAGGED, + BLOCK_ALLOC_MAX, +}; + +static int check_buffer_by_byte(int mem_type, int mode) +{ + char *ptr; + int i, j, item; + bool err; + + mte_switch_mode(mode, MTE_ALLOW_NON_ZERO_TAG); + item = sizeof(sizes)/sizeof(int); + + for (i = 0; i < item; i++) { + ptr = (char *)mte_allocate_memory(sizes[i], mem_type, 0, true); + if (check_allocated_memory(ptr, sizes[i], mem_type, true) != KSFT_PASS) + return KSFT_FAIL; + mte_initialize_current_context(mode, (uintptr_t)ptr, sizes[i]); + /* Set some value in tagged memory */ + for (j = 0; j < sizes[i]; j++) + ptr[j] = '1'; + mte_wait_after_trig(); + err = cur_mte_cxt.fault_valid; + /* Check the buffer whether it is filled. */ + for (j = 0; j < sizes[i] && !err; j++) { + if (ptr[j] != '1') + err = true; + } + mte_free_memory((void *)ptr, sizes[i], mem_type, true); + + if (err) + break; + } + if (!err) + return KSFT_PASS; + else + return KSFT_FAIL; +} + +static int check_buffer_underflow_by_byte(int mem_type, int mode, + int underflow_range) +{ + char *ptr; + int i, j, item, last_index; + bool err; + char *und_ptr = NULL; + + mte_switch_mode(mode, MTE_ALLOW_NON_ZERO_TAG); + item = sizeof(sizes)/sizeof(int); + for (i = 0; i < item; i++) { + ptr = (char *)mte_allocate_memory_tag_range(sizes[i], mem_type, 0, + underflow_range, 0); + if (check_allocated_memory_range(ptr, sizes[i], mem_type, + underflow_range, 0) != KSFT_PASS) + return KSFT_FAIL; + + mte_initialize_current_context(mode, (uintptr_t)ptr, -underflow_range); + last_index = 0; + /* Set some value in tagged memory and make the buffer underflow */ + for (j = sizes[i] - 1; (j >= -underflow_range) && + (cur_mte_cxt.fault_valid == false); j--) { + ptr[j] = '1'; + last_index = j; + } + mte_wait_after_trig(); + err = false; + /* Check whether the buffer is filled */ + for (j = 0; j < sizes[i]; j++) { + if (ptr[j] != '1') { + err = true; + ksft_print_msg("Buffer is not filled at index:%d of ptr:0x%lx\n", + j, ptr); + break; + } + } + if (err) + goto check_buffer_underflow_by_byte_err; + + switch (mode) { + case MTE_NONE_ERR: + if (cur_mte_cxt.fault_valid == true || last_index != -underflow_range) { + err = true; + break; + } + /* There were no fault so the underflow area should be filled */ + und_ptr = (char *) MT_CLEAR_TAG((size_t) ptr - underflow_range); + for (j = 0 ; j < underflow_range; j++) { + if (und_ptr[j] != '1') { + err = true; + break; + } + } + break; + case MTE_ASYNC_ERR: + /* Imprecise fault should occur otherwise return error */ + if (cur_mte_cxt.fault_valid == false) { + err = true; + break; + } + /* + * The imprecise fault is checked after the write to the buffer, + * so the underflow area before the fault should be filled. + */ + und_ptr = (char *) MT_CLEAR_TAG((size_t) ptr); + for (j = last_index ; j < 0 ; j++) { + if (und_ptr[j] != '1') { + err = true; + break; + } + } + break; + case MTE_SYNC_ERR: + /* Precise fault should occur otherwise return error */ + if (!cur_mte_cxt.fault_valid || (last_index != (-1))) { + err = true; + break; + } + /* Underflow area should not be filled */ + und_ptr = (char *) MT_CLEAR_TAG((size_t) ptr); + if (und_ptr[-1] == '1') + err = true; + break; + default: + err = true; + break; + } +check_buffer_underflow_by_byte_err: + mte_free_memory_tag_range((void *)ptr, sizes[i], mem_type, underflow_range, 0); + if (err) + break; + } + return (err ? KSFT_FAIL : KSFT_PASS); +} + +static int check_buffer_overflow_by_byte(int mem_type, int mode, + int overflow_range) +{ + char *ptr; + int i, j, item, last_index; + bool err; + size_t tagged_size, overflow_size; + char *over_ptr = NULL; + + mte_switch_mode(mode, MTE_ALLOW_NON_ZERO_TAG); + item = sizeof(sizes)/sizeof(int); + for (i = 0; i < item; i++) { + ptr = (char *)mte_allocate_memory_tag_range(sizes[i], mem_type, 0, + 0, overflow_range); + if (check_allocated_memory_range(ptr, sizes[i], mem_type, + 0, overflow_range) != KSFT_PASS) + return KSFT_FAIL; + + tagged_size = MT_ALIGN_UP(sizes[i]); + + mte_initialize_current_context(mode, (uintptr_t)ptr, sizes[i] + overflow_range); + + /* Set some value in tagged memory and make the buffer underflow */ + for (j = 0, last_index = 0 ; (j < (sizes[i] + overflow_range)) && + (cur_mte_cxt.fault_valid == false); j++) { + ptr[j] = '1'; + last_index = j; + } + mte_wait_after_trig(); + err = false; + /* Check whether the buffer is filled */ + for (j = 0; j < sizes[i]; j++) { + if (ptr[j] != '1') { + err = true; + ksft_print_msg("Buffer is not filled at index:%d of ptr:0x%lx\n", + j, ptr); + break; + } + } + if (err) + goto check_buffer_overflow_by_byte_err; + + overflow_size = overflow_range - (tagged_size - sizes[i]); + + switch (mode) { + case MTE_NONE_ERR: + if ((cur_mte_cxt.fault_valid == true) || + (last_index != (sizes[i] + overflow_range - 1))) { + err = true; + break; + } + /* There were no fault so the overflow area should be filled */ + over_ptr = (char *) MT_CLEAR_TAG((size_t) ptr + tagged_size); + for (j = 0 ; j < overflow_size; j++) { + if (over_ptr[j] != '1') { + err = true; + break; + } + } + break; + case MTE_ASYNC_ERR: + /* Imprecise fault should occur otherwise return error */ + if (cur_mte_cxt.fault_valid == false) { + err = true; + break; + } + /* + * The imprecise fault is checked after the write to the buffer, + * so the overflow area should be filled before the fault. + */ + over_ptr = (char *) MT_CLEAR_TAG((size_t) ptr); + for (j = tagged_size ; j < last_index; j++) { + if (over_ptr[j] != '1') { + err = true; + break; + } + } + break; + case MTE_SYNC_ERR: + /* Precise fault should occur otherwise return error */ + if (!cur_mte_cxt.fault_valid || (last_index != tagged_size)) { + err = true; + break; + } + /* Underflow area should not be filled */ + over_ptr = (char *) MT_CLEAR_TAG((size_t) ptr + tagged_size); + for (j = 0 ; j < overflow_size; j++) { + if (over_ptr[j] == '1') + err = true; + } + break; + default: + err = true; + break; + } +check_buffer_overflow_by_byte_err: + mte_free_memory_tag_range((void *)ptr, sizes[i], mem_type, 0, overflow_range); + if (err) + break; + } + return (err ? KSFT_FAIL : KSFT_PASS); +} + +static int check_buffer_by_block_iterate(int mem_type, int mode, size_t size) +{ + char *src, *dst; + int j, result = KSFT_PASS; + enum mte_block_test_alloc alloc_type = UNTAGGED_TAGGED; + + for (alloc_type = UNTAGGED_TAGGED; alloc_type < (int) BLOCK_ALLOC_MAX; alloc_type++) { + switch (alloc_type) { + case UNTAGGED_TAGGED: + src = (char *)mte_allocate_memory(size, mem_type, 0, false); + if (check_allocated_memory(src, size, mem_type, false) != KSFT_PASS) + return KSFT_FAIL; + + dst = (char *)mte_allocate_memory(size, mem_type, 0, true); + if (check_allocated_memory(dst, size, mem_type, true) != KSFT_PASS) { + mte_free_memory((void *)src, size, mem_type, false); + return KSFT_FAIL; + } + + break; + case TAGGED_UNTAGGED: + dst = (char *)mte_allocate_memory(size, mem_type, 0, false); + if (check_allocated_memory(dst, size, mem_type, false) != KSFT_PASS) + return KSFT_FAIL; + + src = (char *)mte_allocate_memory(size, mem_type, 0, true); + if (check_allocated_memory(src, size, mem_type, true) != KSFT_PASS) { + mte_free_memory((void *)dst, size, mem_type, false); + return KSFT_FAIL; + } + break; + case TAGGED_TAGGED: + src = (char *)mte_allocate_memory(size, mem_type, 0, true); + if (check_allocated_memory(src, size, mem_type, true) != KSFT_PASS) + return KSFT_FAIL; + + dst = (char *)mte_allocate_memory(size, mem_type, 0, true); + if (check_allocated_memory(dst, size, mem_type, true) != KSFT_PASS) { + mte_free_memory((void *)src, size, mem_type, true); + return KSFT_FAIL; + } + break; + default: + return KSFT_FAIL; + } + + cur_mte_cxt.fault_valid = false; + result = KSFT_PASS; + mte_initialize_current_context(mode, (uintptr_t)dst, size); + /* Set some value in memory and copy*/ + memset((void *)src, (int)'1', size); + memcpy((void *)dst, (void *)src, size); + mte_wait_after_trig(); + if (cur_mte_cxt.fault_valid) { + result = KSFT_FAIL; + goto check_buffer_by_block_err; + } + /* Check the buffer whether it is filled. */ + for (j = 0; j < size; j++) { + if (src[j] != dst[j] || src[j] != '1') { + result = KSFT_FAIL; + break; + } + } +check_buffer_by_block_err: + mte_free_memory((void *)src, size, mem_type, + MT_FETCH_TAG((uintptr_t)src) ? true : false); + mte_free_memory((void *)dst, size, mem_type, + MT_FETCH_TAG((uintptr_t)dst) ? true : false); + if (result != KSFT_PASS) + return result; + } + return result; +} + +static int check_buffer_by_block(int mem_type, int mode) +{ + int i, item, result = KSFT_PASS; + + mte_switch_mode(mode, MTE_ALLOW_NON_ZERO_TAG); + item = sizeof(sizes)/sizeof(int); + cur_mte_cxt.fault_valid = false; + for (i = 0; i < item; i++) { + result = check_buffer_by_block_iterate(mem_type, mode, sizes[i]); + if (result != KSFT_PASS) + break; + } + return result; +} + +static int compare_memory_tags(char *ptr, size_t size, int tag) +{ + int i, new_tag; + + for (i = 0 ; i < size ; i += MT_GRANULE_SIZE) { + new_tag = MT_FETCH_TAG((uintptr_t)(mte_get_tag_address(ptr + i))); + if (tag != new_tag) { + ksft_print_msg("FAIL: child mte tag mismatch\n"); + return KSFT_FAIL; + } + } + return KSFT_PASS; +} + +static int check_memory_initial_tags(int mem_type, int mode, int mapping) +{ + char *ptr; + int run, fd; + int total = sizeof(sizes)/sizeof(int); + + mte_switch_mode(mode, MTE_ALLOW_NON_ZERO_TAG); + for (run = 0; run < total; run++) { + /* check initial tags for anonymous mmap */ + ptr = (char *)mte_allocate_memory(sizes[run], mem_type, mapping, false); + if (check_allocated_memory(ptr, sizes[run], mem_type, false) != KSFT_PASS) + return KSFT_FAIL; + if (compare_memory_tags(ptr, sizes[run], 0) != KSFT_PASS) { + mte_free_memory((void *)ptr, sizes[run], mem_type, false); + return KSFT_FAIL; + } + mte_free_memory((void *)ptr, sizes[run], mem_type, false); + + /* check initial tags for file mmap */ + fd = create_temp_file(); + if (fd == -1) + return KSFT_FAIL; + ptr = (char *)mte_allocate_file_memory(sizes[run], mem_type, mapping, false, fd); + if (check_allocated_memory(ptr, sizes[run], mem_type, false) != KSFT_PASS) { + close(fd); + return KSFT_FAIL; + } + if (compare_memory_tags(ptr, sizes[run], 0) != KSFT_PASS) { + mte_free_memory((void *)ptr, sizes[run], mem_type, false); + close(fd); + return KSFT_FAIL; + } + mte_free_memory((void *)ptr, sizes[run], mem_type, false); + close(fd); + } + return KSFT_PASS; +} + +int main(int argc, char *argv[]) +{ + int err; + size_t page_size = getpagesize(); + int item = sizeof(sizes)/sizeof(int); + + sizes[item - 3] = page_size - 1; + sizes[item - 2] = page_size; + sizes[item - 1] = page_size + 1; + + err = mte_default_setup(); + if (err) + return err; + + /* Register SIGSEGV handler */ + mte_register_signal(SIGSEGV, mte_default_handler); + + /* Buffer by byte tests */ + evaluate_test(check_buffer_by_byte(USE_MMAP, MTE_SYNC_ERR), + "Check buffer correctness by byte with sync err mode and mmap memory\n"); + evaluate_test(check_buffer_by_byte(USE_MMAP, MTE_ASYNC_ERR), + "Check buffer correctness by byte with async err mode and mmap memory\n"); + evaluate_test(check_buffer_by_byte(USE_MPROTECT, MTE_SYNC_ERR), + "Check buffer correctness by byte with sync err mode and mmap/mprotect memory\n"); + evaluate_test(check_buffer_by_byte(USE_MPROTECT, MTE_ASYNC_ERR), + "Check buffer correctness by byte with async err mode and mmap/mprotect memory\n"); + + /* Check buffer underflow with underflow size as 16 */ + evaluate_test(check_buffer_underflow_by_byte(USE_MMAP, MTE_SYNC_ERR, MT_GRANULE_SIZE), + "Check buffer write underflow by byte with sync mode and mmap memory\n"); + evaluate_test(check_buffer_underflow_by_byte(USE_MMAP, MTE_ASYNC_ERR, MT_GRANULE_SIZE), + "Check buffer write underflow by byte with async mode and mmap memory\n"); + evaluate_test(check_buffer_underflow_by_byte(USE_MMAP, MTE_NONE_ERR, MT_GRANULE_SIZE), + "Check buffer write underflow by byte with tag check fault ignore and mmap memory\n"); + + /* Check buffer underflow with underflow size as page size */ + evaluate_test(check_buffer_underflow_by_byte(USE_MMAP, MTE_SYNC_ERR, page_size), + "Check buffer write underflow by byte with sync mode and mmap memory\n"); + evaluate_test(check_buffer_underflow_by_byte(USE_MMAP, MTE_ASYNC_ERR, page_size), + "Check buffer write underflow by byte with async mode and mmap memory\n"); + evaluate_test(check_buffer_underflow_by_byte(USE_MMAP, MTE_NONE_ERR, page_size), + "Check buffer write underflow by byte with tag check fault ignore and mmap memory\n"); + + /* Check buffer overflow with overflow size as 16 */ + evaluate_test(check_buffer_overflow_by_byte(USE_MMAP, MTE_SYNC_ERR, MT_GRANULE_SIZE), + "Check buffer write overflow by byte with sync mode and mmap memory\n"); + evaluate_test(check_buffer_overflow_by_byte(USE_MMAP, MTE_ASYNC_ERR, MT_GRANULE_SIZE), + "Check buffer write overflow by byte with async mode and mmap memory\n"); + evaluate_test(check_buffer_overflow_by_byte(USE_MMAP, MTE_NONE_ERR, MT_GRANULE_SIZE), + "Check buffer write overflow by byte with tag fault ignore mode and mmap memory\n"); + + /* Buffer by block tests */ + evaluate_test(check_buffer_by_block(USE_MMAP, MTE_SYNC_ERR), + "Check buffer write correctness by block with sync mode and mmap memory\n"); + evaluate_test(check_buffer_by_block(USE_MMAP, MTE_ASYNC_ERR), + "Check buffer write correctness by block with async mode and mmap memory\n"); + evaluate_test(check_buffer_by_block(USE_MMAP, MTE_NONE_ERR), + "Check buffer write correctness by block with tag fault ignore and mmap memory\n"); + + /* Initial tags are supposed to be 0 */ + evaluate_test(check_memory_initial_tags(USE_MMAP, MTE_SYNC_ERR, MAP_PRIVATE), + "Check initial tags with private mapping, sync error mode and mmap memory\n"); + evaluate_test(check_memory_initial_tags(USE_MPROTECT, MTE_SYNC_ERR, MAP_PRIVATE), + "Check initial tags with private mapping, sync error mode and mmap/mprotect memory\n"); + evaluate_test(check_memory_initial_tags(USE_MMAP, MTE_SYNC_ERR, MAP_SHARED), + "Check initial tags with shared mapping, sync error mode and mmap memory\n"); + evaluate_test(check_memory_initial_tags(USE_MPROTECT, MTE_SYNC_ERR, MAP_SHARED), + "Check initial tags with shared mapping, sync error mode and mmap/mprotect memory\n"); + + mte_restore_setup(); + ksft_print_cnts(); + return ksft_get_fail_cnt() == 0 ? KSFT_PASS : KSFT_FAIL; +} diff --git a/tools/testing/selftests/arm64/mte/mte_common_util.c b/tools/testing/selftests/arm64/mte/mte_common_util.c new file mode 100644 index 000000000000..39f8908988ea --- /dev/null +++ b/tools/testing/selftests/arm64/mte/mte_common_util.c @@ -0,0 +1,341 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2020 ARM Limited + +#include <fcntl.h> +#include <sched.h> +#include <signal.h> +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> + +#include <linux/auxvec.h> +#include <sys/auxv.h> +#include <sys/mman.h> +#include <sys/prctl.h> + +#include <asm/hwcap.h> + +#include "kselftest.h" +#include "mte_common_util.h" +#include "mte_def.h" + +#define INIT_BUFFER_SIZE 256 + +struct mte_fault_cxt cur_mte_cxt; +static unsigned int mte_cur_mode; +static unsigned int mte_cur_pstate_tco; + +void mte_default_handler(int signum, siginfo_t *si, void *uc) +{ + unsigned long addr = (unsigned long)si->si_addr; + + if (signum == SIGSEGV) { +#ifdef DEBUG + ksft_print_msg("INFO: SIGSEGV signal at pc=%lx, fault addr=%lx, si_code=%lx\n", + ((ucontext_t *)uc)->uc_mcontext.pc, addr, si->si_code); +#endif + if (si->si_code == SEGV_MTEAERR) { + if (cur_mte_cxt.trig_si_code == si->si_code) + cur_mte_cxt.fault_valid = true; + return; + } + /* Compare the context for precise error */ + else if (si->si_code == SEGV_MTESERR) { + if (cur_mte_cxt.trig_si_code == si->si_code && + ((cur_mte_cxt.trig_range >= 0 && + addr >= MT_CLEAR_TAG(cur_mte_cxt.trig_addr) && + addr <= (MT_CLEAR_TAG(cur_mte_cxt.trig_addr) + cur_mte_cxt.trig_range)) || + (cur_mte_cxt.trig_range < 0 && + addr <= MT_CLEAR_TAG(cur_mte_cxt.trig_addr) && + addr >= (MT_CLEAR_TAG(cur_mte_cxt.trig_addr) + cur_mte_cxt.trig_range)))) { + cur_mte_cxt.fault_valid = true; + /* Adjust the pc by 4 */ + ((ucontext_t *)uc)->uc_mcontext.pc += 4; + } else { + ksft_print_msg("Invalid MTE synchronous exception caught!\n"); + exit(1); + } + } else { + ksft_print_msg("Unknown SIGSEGV exception caught!\n"); + exit(1); + } + } else if (signum == SIGBUS) { + ksft_print_msg("INFO: SIGBUS signal at pc=%lx, fault addr=%lx, si_code=%lx\n", + ((ucontext_t *)uc)->uc_mcontext.pc, addr, si->si_code); + if ((cur_mte_cxt.trig_range >= 0 && + addr >= MT_CLEAR_TAG(cur_mte_cxt.trig_addr) && + addr <= (MT_CLEAR_TAG(cur_mte_cxt.trig_addr) + cur_mte_cxt.trig_range)) || + (cur_mte_cxt.trig_range < 0 && + addr <= MT_CLEAR_TAG(cur_mte_cxt.trig_addr) && + addr >= (MT_CLEAR_TAG(cur_mte_cxt.trig_addr) + cur_mte_cxt.trig_range))) { + cur_mte_cxt.fault_valid = true; + /* Adjust the pc by 4 */ + ((ucontext_t *)uc)->uc_mcontext.pc += 4; + } + } +} + +void mte_register_signal(int signal, void (*handler)(int, siginfo_t *, void *)) +{ + struct sigaction sa; + + sa.sa_sigaction = handler; + sa.sa_flags = SA_SIGINFO; + sigemptyset(&sa.sa_mask); + sigaction(signal, &sa, NULL); +} + +void mte_wait_after_trig(void) +{ + sched_yield(); +} + +void *mte_insert_tags(void *ptr, size_t size) +{ + void *tag_ptr; + int align_size; + + if (!ptr || (unsigned long)(ptr) & MT_ALIGN_GRANULE) { + ksft_print_msg("FAIL: Addr=%lx: invalid\n", ptr); + return NULL; + } + align_size = MT_ALIGN_UP(size); + tag_ptr = mte_insert_random_tag(ptr); + mte_set_tag_address_range(tag_ptr, align_size); + return tag_ptr; +} + +void mte_clear_tags(void *ptr, size_t size) +{ + if (!ptr || (unsigned long)(ptr) & MT_ALIGN_GRANULE) { + ksft_print_msg("FAIL: Addr=%lx: invalid\n", ptr); + return; + } + size = MT_ALIGN_UP(size); + ptr = (void *)MT_CLEAR_TAG((unsigned long)ptr); + mte_clear_tag_address_range(ptr, size); +} + +static void *__mte_allocate_memory_range(size_t size, int mem_type, int mapping, + size_t range_before, size_t range_after, + bool tags, int fd) +{ + void *ptr; + int prot_flag, map_flag; + size_t entire_size = size + range_before + range_after; + + if (mem_type != USE_MALLOC && mem_type != USE_MMAP && + mem_type != USE_MPROTECT) { + ksft_print_msg("FAIL: Invalid allocate request\n"); + return NULL; + } + if (mem_type == USE_MALLOC) + return malloc(entire_size) + range_before; + + prot_flag = PROT_READ | PROT_WRITE; + if (mem_type == USE_MMAP) + prot_flag |= PROT_MTE; + + map_flag = mapping; + if (fd == -1) + map_flag = MAP_ANONYMOUS | map_flag; + if (!(mapping & MAP_SHARED)) + map_flag |= MAP_PRIVATE; + ptr = mmap(NULL, entire_size, prot_flag, map_flag, fd, 0); + if (ptr == MAP_FAILED) { + ksft_print_msg("FAIL: mmap allocation\n"); + return NULL; + } + if (mem_type == USE_MPROTECT) { + if (mprotect(ptr, entire_size, prot_flag | PROT_MTE)) { + munmap(ptr, size); + ksft_print_msg("FAIL: mprotect PROT_MTE property\n"); + return NULL; + } + } + if (tags) + ptr = mte_insert_tags(ptr + range_before, size); + return ptr; +} + +void *mte_allocate_memory_tag_range(size_t size, int mem_type, int mapping, + size_t range_before, size_t range_after) +{ + return __mte_allocate_memory_range(size, mem_type, mapping, range_before, + range_after, true, -1); +} + +void *mte_allocate_memory(size_t size, int mem_type, int mapping, bool tags) +{ + return __mte_allocate_memory_range(size, mem_type, mapping, 0, 0, tags, -1); +} + +void *mte_allocate_file_memory(size_t size, int mem_type, int mapping, bool tags, int fd) +{ + int index; + char buffer[INIT_BUFFER_SIZE]; + + if (mem_type != USE_MPROTECT && mem_type != USE_MMAP) { + ksft_print_msg("FAIL: Invalid mmap file request\n"); + return NULL; + } + /* Initialize the file for mappable size */ + lseek(fd, 0, SEEK_SET); + for (index = INIT_BUFFER_SIZE; index < size; index += INIT_BUFFER_SIZE) + write(fd, buffer, INIT_BUFFER_SIZE); + index -= INIT_BUFFER_SIZE; + write(fd, buffer, size - index); + return __mte_allocate_memory_range(size, mem_type, mapping, 0, 0, tags, fd); +} + +void *mte_allocate_file_memory_tag_range(size_t size, int mem_type, int mapping, + size_t range_before, size_t range_after, int fd) +{ + int index; + char buffer[INIT_BUFFER_SIZE]; + int map_size = size + range_before + range_after; + + if (mem_type != USE_MPROTECT && mem_type != USE_MMAP) { + ksft_print_msg("FAIL: Invalid mmap file request\n"); + return NULL; + } + /* Initialize the file for mappable size */ + lseek(fd, 0, SEEK_SET); + for (index = INIT_BUFFER_SIZE; index < map_size; index += INIT_BUFFER_SIZE) + write(fd, buffer, INIT_BUFFER_SIZE); + index -= INIT_BUFFER_SIZE; + write(fd, buffer, map_size - index); + return __mte_allocate_memory_range(size, mem_type, mapping, range_before, + range_after, true, fd); +} + +static void __mte_free_memory_range(void *ptr, size_t size, int mem_type, + size_t range_before, size_t range_after, bool tags) +{ + switch (mem_type) { + case USE_MALLOC: + free(ptr - range_before); + break; + case USE_MMAP: + case USE_MPROTECT: + if (tags) + mte_clear_tags(ptr, size); + munmap(ptr - range_before, size + range_before + range_after); + break; + default: + ksft_print_msg("FAIL: Invalid free request\n"); + break; + } +} + +void mte_free_memory_tag_range(void *ptr, size_t size, int mem_type, + size_t range_before, size_t range_after) +{ + __mte_free_memory_range(ptr, size, mem_type, range_before, range_after, true); +} + +void mte_free_memory(void *ptr, size_t size, int mem_type, bool tags) +{ + __mte_free_memory_range(ptr, size, mem_type, 0, 0, tags); +} + +void mte_initialize_current_context(int mode, uintptr_t ptr, ssize_t range) +{ + cur_mte_cxt.fault_valid = false; + cur_mte_cxt.trig_addr = ptr; + cur_mte_cxt.trig_range = range; + if (mode == MTE_SYNC_ERR) + cur_mte_cxt.trig_si_code = SEGV_MTESERR; + else if (mode == MTE_ASYNC_ERR) + cur_mte_cxt.trig_si_code = SEGV_MTEAERR; + else + cur_mte_cxt.trig_si_code = 0; +} + +int mte_switch_mode(int mte_option, unsigned long incl_mask) +{ + unsigned long en = 0; + + if (!(mte_option == MTE_SYNC_ERR || mte_option == MTE_ASYNC_ERR || + mte_option == MTE_NONE_ERR || incl_mask <= MTE_ALLOW_NON_ZERO_TAG)) { + ksft_print_msg("FAIL: Invalid mte config option\n"); + return -EINVAL; + } + en = PR_TAGGED_ADDR_ENABLE; + if (mte_option == MTE_SYNC_ERR) + en |= PR_MTE_TCF_SYNC; + else if (mte_option == MTE_ASYNC_ERR) + en |= PR_MTE_TCF_ASYNC; + else if (mte_option == MTE_NONE_ERR) + en |= PR_MTE_TCF_NONE; + + en |= (incl_mask << PR_MTE_TAG_SHIFT); + /* Enable address tagging ABI, mte error reporting mode and tag inclusion mask. */ + if (!prctl(PR_SET_TAGGED_ADDR_CTRL, en, 0, 0, 0) == 0) { + ksft_print_msg("FAIL:prctl PR_SET_TAGGED_ADDR_CTRL for mte mode\n"); + return -EINVAL; + } + return 0; +} + +#define ID_AA64PFR1_MTE_SHIFT 8 +#define ID_AA64PFR1_MTE 2 + +int mte_default_setup(void) +{ + unsigned long hwcaps = getauxval(AT_HWCAP); + unsigned long en = 0; + int ret; + + if (!(hwcaps & HWCAP_CPUID)) { + ksft_print_msg("FAIL: CPUID registers unavailable\n"); + return KSFT_FAIL; + } + /* Read ID_AA64PFR1_EL1 register */ + asm volatile("mrs %0, id_aa64pfr1_el1" : "=r"(hwcaps) : : "memory"); + if (((hwcaps >> ID_AA64PFR1_MTE_SHIFT) & MT_TAG_MASK) != ID_AA64PFR1_MTE) { + ksft_print_msg("FAIL: MTE features unavailable\n"); + return KSFT_SKIP; + } + /* Get current mte mode */ + ret = prctl(PR_GET_TAGGED_ADDR_CTRL, en, 0, 0, 0); + if (ret < 0) { + ksft_print_msg("FAIL:prctl PR_GET_TAGGED_ADDR_CTRL with error =%d\n", ret); + return KSFT_FAIL; + } + if (ret & PR_MTE_TCF_SYNC) + mte_cur_mode = MTE_SYNC_ERR; + else if (ret & PR_MTE_TCF_ASYNC) + mte_cur_mode = MTE_ASYNC_ERR; + else if (ret & PR_MTE_TCF_NONE) + mte_cur_mode = MTE_NONE_ERR; + + mte_cur_pstate_tco = mte_get_pstate_tco(); + /* Disable PSTATE.TCO */ + mte_disable_pstate_tco(); + return 0; +} + +void mte_restore_setup(void) +{ + mte_switch_mode(mte_cur_mode, MTE_ALLOW_NON_ZERO_TAG); + if (mte_cur_pstate_tco == MT_PSTATE_TCO_EN) + mte_enable_pstate_tco(); + else if (mte_cur_pstate_tco == MT_PSTATE_TCO_DIS) + mte_disable_pstate_tco(); +} + +int create_temp_file(void) +{ + int fd; + char filename[] = "/dev/shm/tmp_XXXXXX"; + + /* Create a file in the tmpfs filesystem */ + fd = mkstemp(&filename[0]); + if (fd == -1) { + ksft_print_msg("FAIL: Unable to open temporary file\n"); + return 0; + } + unlink(&filename[0]); + return fd; +} diff --git a/tools/testing/selftests/arm64/mte/mte_common_util.h b/tools/testing/selftests/arm64/mte/mte_common_util.h new file mode 100644 index 000000000000..45160e061a0e --- /dev/null +++ b/tools/testing/selftests/arm64/mte/mte_common_util.h @@ -0,0 +1,117 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Copyright (C) 2020 ARM Limited */ + +#ifndef _MTE_COMMON_UTIL_H +#define _MTE_COMMON_UTIL_H + +#include <signal.h> +#include <stdbool.h> +#include <stdlib.h> +#include <sys/auxv.h> +#include <sys/mman.h> +#include <sys/prctl.h> +#include "mte_def.h" +#include "kselftest.h" + +enum mte_mem_type { + USE_MALLOC, + USE_MMAP, + USE_MPROTECT, +}; + +enum mte_mode { + MTE_NONE_ERR, + MTE_SYNC_ERR, + MTE_ASYNC_ERR, +}; + +struct mte_fault_cxt { + /* Address start which triggers mte tag fault */ + unsigned long trig_addr; + /* Address range for mte tag fault and negative value means underflow */ + ssize_t trig_range; + /* siginfo si code */ + unsigned long trig_si_code; + /* Flag to denote if correct fault caught */ + bool fault_valid; +}; + +extern struct mte_fault_cxt cur_mte_cxt; + +/* MTE utility functions */ +void mte_default_handler(int signum, siginfo_t *si, void *uc); +void mte_register_signal(int signal, void (*handler)(int, siginfo_t *, void *)); +void mte_wait_after_trig(void); +void *mte_allocate_memory(size_t size, int mem_type, int mapping, bool tags); +void *mte_allocate_memory_tag_range(size_t size, int mem_type, int mapping, + size_t range_before, size_t range_after); +void *mte_allocate_file_memory(size_t size, int mem_type, int mapping, + bool tags, int fd); +void *mte_allocate_file_memory_tag_range(size_t size, int mem_type, int mapping, + size_t range_before, size_t range_after, int fd); +void mte_free_memory(void *ptr, size_t size, int mem_type, bool tags); +void mte_free_memory_tag_range(void *ptr, size_t size, int mem_type, + size_t range_before, size_t range_after); +void *mte_insert_tags(void *ptr, size_t size); +void mte_clear_tags(void *ptr, size_t size); +int mte_default_setup(void); +void mte_restore_setup(void); +int mte_switch_mode(int mte_option, unsigned long incl_mask); +void mte_initialize_current_context(int mode, uintptr_t ptr, ssize_t range); + +/* Common utility functions */ +int create_temp_file(void); + +/* Assembly MTE utility functions */ +void *mte_insert_random_tag(void *ptr); +void *mte_get_tag_address(void *ptr); +void mte_set_tag_address_range(void *ptr, int range); +void mte_clear_tag_address_range(void *ptr, int range); +void mte_disable_pstate_tco(void); +void mte_enable_pstate_tco(void); +unsigned int mte_get_pstate_tco(void); + +/* Test framework static inline functions/macros */ +static inline void evaluate_test(int err, const char *msg) +{ + if (err == KSFT_PASS) + ksft_test_result_pass(msg); + else if (err == KSFT_FAIL) + ksft_test_result_fail(msg); +} + +static inline int check_allocated_memory(void *ptr, size_t size, + int mem_type, bool tags) +{ + if (ptr == NULL) { + ksft_print_msg("FAIL: memory allocation\n"); + return KSFT_FAIL; + } + + if (tags && !MT_FETCH_TAG((uintptr_t)ptr)) { + ksft_print_msg("FAIL: tag not found at addr(%p)\n", ptr); + mte_free_memory((void *)ptr, size, mem_type, false); + return KSFT_FAIL; + } + + return KSFT_PASS; +} + +static inline int check_allocated_memory_range(void *ptr, size_t size, int mem_type, + size_t range_before, size_t range_after) +{ + if (ptr == NULL) { + ksft_print_msg("FAIL: memory allocation\n"); + return KSFT_FAIL; + } + + if (!MT_FETCH_TAG((uintptr_t)ptr)) { + ksft_print_msg("FAIL: tag not found at addr(%p)\n", ptr); + mte_free_memory_tag_range((void *)ptr, size, mem_type, range_before, + range_after); + return KSFT_FAIL; + } + return KSFT_PASS; +} + +#endif /* _MTE_COMMON_UTIL_H */ diff --git a/tools/testing/selftests/arm64/mte/mte_def.h b/tools/testing/selftests/arm64/mte/mte_def.h new file mode 100644 index 000000000000..9b188254b61a --- /dev/null +++ b/tools/testing/selftests/arm64/mte/mte_def.h @@ -0,0 +1,60 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Copyright (C) 2020 ARM Limited */ + +/* + * Below definitions may be found in kernel headers, However, they are + * redefined here to decouple the MTE selftests compilations from them. + */ +#ifndef SEGV_MTEAERR +#define SEGV_MTEAERR 8 +#endif +#ifndef SEGV_MTESERR +#define SEGV_MTESERR 9 +#endif +#ifndef PROT_MTE +#define PROT_MTE 0x20 +#endif +#ifndef HWCAP2_MTE +#define HWCAP2_MTE (1 << 18) +#endif + +#ifndef PR_MTE_TCF_SHIFT +#define PR_MTE_TCF_SHIFT 1 +#endif +#ifndef PR_MTE_TCF_NONE +#define PR_MTE_TCF_NONE (0UL << PR_MTE_TCF_SHIFT) +#endif +#ifndef PR_MTE_TCF_SYNC +#define PR_MTE_TCF_SYNC (1UL << PR_MTE_TCF_SHIFT) +#endif +#ifndef PR_MTE_TCF_ASYNC +#define PR_MTE_TCF_ASYNC (2UL << PR_MTE_TCF_SHIFT) +#endif +#ifndef PR_MTE_TAG_SHIFT +#define PR_MTE_TAG_SHIFT 3 +#endif + +/* MTE Hardware feature definitions below. */ +#define MT_TAG_SHIFT 56 +#define MT_TAG_MASK 0xFUL +#define MT_FREE_TAG 0x0UL +#define MT_GRANULE_SIZE 16 +#define MT_TAG_COUNT 16 +#define MT_INCLUDE_TAG_MASK 0xFFFF +#define MT_EXCLUDE_TAG_MASK 0x0 + +#define MT_ALIGN_GRANULE (MT_GRANULE_SIZE - 1) +#define MT_CLEAR_TAG(x) ((x) & ~(MT_TAG_MASK << MT_TAG_SHIFT)) +#define MT_SET_TAG(x, y) ((x) | (y << MT_TAG_SHIFT)) +#define MT_FETCH_TAG(x) ((x >> MT_TAG_SHIFT) & (MT_TAG_MASK)) +#define MT_ALIGN_UP(x) ((x + MT_ALIGN_GRANULE) & ~(MT_ALIGN_GRANULE)) + +#define MT_PSTATE_TCO_SHIFT 25 +#define MT_PSTATE_TCO_MASK ~(0x1 << MT_PSTATE_TCO_SHIFT) +#define MT_PSTATE_TCO_EN 1 +#define MT_PSTATE_TCO_DIS 0 + +#define MT_EXCLUDE_TAG(x) (1 << (x)) +#define MT_INCLUDE_VALID_TAG(x) (MT_INCLUDE_TAG_MASK ^ MT_EXCLUDE_TAG(x)) +#define MT_INCLUDE_VALID_TAGS(x) (MT_INCLUDE_TAG_MASK ^ (x)) +#define MTE_ALLOW_NON_ZERO_TAG MT_INCLUDE_VALID_TAG(0) diff --git a/tools/testing/selftests/arm64/mte/mte_helper.S b/tools/testing/selftests/arm64/mte/mte_helper.S new file mode 100644 index 000000000000..48e049fbad9a --- /dev/null +++ b/tools/testing/selftests/arm64/mte/mte_helper.S @@ -0,0 +1,114 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Copyright (C) 2020 ARM Limited */ + +#include "mte_def.h" + +#define ENTRY(name) \ + .globl name ;\ + .p2align 2;\ + .type name, @function ;\ +name: + +#define ENDPROC(name) \ + .size name, .-name ; + + .text +/* + * mte_insert_random_tag: Insert random tag and might be same as the source tag if + * the source pointer has it. + * Input: + * x0 - source pointer with a tag/no-tag + * Return: + * x0 - pointer with random tag + */ +ENTRY(mte_insert_random_tag) + irg x0, x0, xzr + ret +ENDPROC(mte_insert_random_tag) + +/* + * mte_get_tag_address: Get the tag from given address. + * Input: + * x0 - source pointer + * Return: + * x0 - pointer with appended tag + */ +ENTRY(mte_get_tag_address) + ldg x0, [x0] + ret +ENDPROC(mte_get_tag_address) + +/* + * mte_set_tag_address_range: Set the tag range from the given address + * Input: + * x0 - source pointer with tag data + * x1 - range + * Return: + * none + */ +ENTRY(mte_set_tag_address_range) + cbz x1, 2f +1: + stg x0, [x0, #0x0] + add x0, x0, #MT_GRANULE_SIZE + sub x1, x1, #MT_GRANULE_SIZE + cbnz x1, 1b +2: + ret +ENDPROC(mte_set_tag_address_range) + +/* + * mt_clear_tag_address_range: Clear the tag range from the given address + * Input: + * x0 - source pointer with tag data + * x1 - range + * Return: + * none + */ +ENTRY(mte_clear_tag_address_range) + cbz x1, 2f +1: + stzg x0, [x0, #0x0] + add x0, x0, #MT_GRANULE_SIZE + sub x1, x1, #MT_GRANULE_SIZE + cbnz x1, 1b +2: + ret +ENDPROC(mte_clear_tag_address_range) + +/* + * mte_enable_pstate_tco: Enable PSTATE.TCO (tag check override) field + * Input: + * none + * Return: + * none + */ +ENTRY(mte_enable_pstate_tco) + msr tco, #MT_PSTATE_TCO_EN + ret +ENDPROC(mte_enable_pstate_tco) + +/* + * mte_disable_pstate_tco: Disable PSTATE.TCO (tag check override) field + * Input: + * none + * Return: + * none + */ +ENTRY(mte_disable_pstate_tco) + msr tco, #MT_PSTATE_TCO_DIS + ret +ENDPROC(mte_disable_pstate_tco) + +/* + * mte_get_pstate_tco: Get PSTATE.TCO (tag check override) field + * Input: + * none + * Return: + * x0 + */ +ENTRY(mte_get_pstate_tco) + mrs x0, tco + ubfx x0, x0, #MT_PSTATE_TCO_SHIFT, #1 + ret +ENDPROC(mte_get_pstate_tco)

This test covers the mte memory behaviour of the forked process with different mapping properties and flags. It checks that all bytes of forked child memory are accessible with the same tag as that of the parent and memory accessed outside the tag range causes fault to occur.

Cc: Shuah Khan shuah@kernel.org Cc: Catalin Marinas catalin.marinas@arm.com Cc: Will Deacon will@kernel.org Co-developed-by: Gabor Kertesz gabor.kertesz@arm.com Signed-off-by: Gabor Kertesz gabor.kertesz@arm.com Signed-off-by: Amit Daniel Kachhap amit.kachhap@arm.com --- tools/testing/selftests/arm64/mte/.gitignore | 1 + .../selftests/arm64/mte/check_child_memory.c | 195 ++++++++++++++++++ 2 files changed, 196 insertions(+) create mode 100644 tools/testing/selftests/arm64/mte/check_child_memory.c

diff --git a/tools/testing/selftests/arm64/mte/.gitignore b/tools/testing/selftests/arm64/mte/.gitignore index c3fca255d3d6..b5fcc0fb4d97 100644 --- a/tools/testing/selftests/arm64/mte/.gitignore +++ b/tools/testing/selftests/arm64/mte/.gitignore @@ -1,2 +1,3 @@ check_buffer_fill check_tags_inclusion +check_child_memory diff --git a/tools/testing/selftests/arm64/mte/check_child_memory.c b/tools/testing/selftests/arm64/mte/check_child_memory.c new file mode 100644 index 000000000000..97bebdecd29e --- /dev/null +++ b/tools/testing/selftests/arm64/mte/check_child_memory.c @@ -0,0 +1,195 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2020 ARM Limited + +#define _GNU_SOURCE + +#include <errno.h> +#include <signal.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <ucontext.h> +#include <sys/wait.h> + +#include "kselftest.h" +#include "mte_common_util.h" +#include "mte_def.h" + +#define BUFFER_SIZE (5 * MT_GRANULE_SIZE) +#define RUNS (MT_TAG_COUNT) +#define UNDERFLOW MT_GRANULE_SIZE +#define OVERFLOW MT_GRANULE_SIZE + +static size_t page_size; +static int sizes[] = { + 1, 537, 989, 1269, MT_GRANULE_SIZE - 1, MT_GRANULE_SIZE, + /* page size - 1*/ 0, /* page_size */ 0, /* page size + 1 */ 0 +}; + +static int check_child_tag_inheritance(char *ptr, int size, int mode) +{ + int i, parent_tag, child_tag, fault, child_status; + pid_t child; + + parent_tag = MT_FETCH_TAG((uintptr_t)ptr); + fault = 0; + + child = fork(); + if (child == -1) { + ksft_print_msg("FAIL: child process creation\n"); + return KSFT_FAIL; + } else if (child == 0) { + mte_initialize_current_context(mode, (uintptr_t)ptr, size); + /* Do copy on write */ + memset(ptr, '1', size); + mte_wait_after_trig(); + if (cur_mte_cxt.fault_valid == true) { + fault = 1; + goto check_child_tag_inheritance_err; + } + for (i = 0 ; i < size ; i += MT_GRANULE_SIZE) { + child_tag = MT_FETCH_TAG((uintptr_t)(mte_get_tag_address(ptr + i))); + if (parent_tag != child_tag) { + ksft_print_msg("FAIL: child mte tag mismatch\n"); + fault = 1; + goto check_child_tag_inheritance_err; + } + } + mte_initialize_current_context(mode, (uintptr_t)ptr, -UNDERFLOW); + memset(ptr - UNDERFLOW, '2', UNDERFLOW); + mte_wait_after_trig(); + if (cur_mte_cxt.fault_valid == false) { + fault = 1; + goto check_child_tag_inheritance_err; + } + mte_initialize_current_context(mode, (uintptr_t)ptr, size + OVERFLOW); + memset(ptr + size, '3', OVERFLOW); + mte_wait_after_trig(); + if (cur_mte_cxt.fault_valid == false) { + fault = 1; + goto check_child_tag_inheritance_err; + } +check_child_tag_inheritance_err: + _exit(fault); + } + /* Wait for child process to terminate */ + wait(&child_status); + if (WIFEXITED(child_status)) + fault = WEXITSTATUS(child_status); + else + fault = 1; + return (fault) ? KSFT_FAIL : KSFT_PASS; +} + +static int check_child_memory_mapping(int mem_type, int mode, int mapping) +{ + char *ptr; + int run, result; + int item = sizeof(sizes)/sizeof(int); + + item = sizeof(sizes)/sizeof(int); + mte_switch_mode(mode, MTE_ALLOW_NON_ZERO_TAG); + for (run = 0; run < item; run++) { + ptr = (char *)mte_allocate_memory_tag_range(sizes[run], mem_type, mapping, + UNDERFLOW, OVERFLOW); + if (check_allocated_memory_range(ptr, sizes[run], mem_type, + UNDERFLOW, OVERFLOW) != KSFT_PASS) + return KSFT_FAIL; + result = check_child_tag_inheritance(ptr, sizes[run], mode); + mte_free_memory_tag_range((void *)ptr, sizes[run], mem_type, UNDERFLOW, OVERFLOW); + if (result == KSFT_FAIL) + return result; + } + return KSFT_PASS; +} + +static int check_child_file_mapping(int mem_type, int mode, int mapping) +{ + char *ptr, *map_ptr; + int run, fd, map_size, result = KSFT_PASS; + int total = sizeof(sizes)/sizeof(int); + + mte_switch_mode(mode, MTE_ALLOW_NON_ZERO_TAG); + for (run = 0; run < total; run++) { + fd = create_temp_file(); + if (fd == -1) + return KSFT_FAIL; + + map_size = sizes[run] + OVERFLOW + UNDERFLOW; + map_ptr = (char *)mte_allocate_file_memory(map_size, mem_type, mapping, false, fd); + if (check_allocated_memory(map_ptr, map_size, mem_type, false) != KSFT_PASS) { + close(fd); + return KSFT_FAIL; + } + ptr = map_ptr + UNDERFLOW; + mte_initialize_current_context(mode, (uintptr_t)ptr, sizes[run]); + /* Only mte enabled memory will allow tag insertion */ + ptr = mte_insert_tags((void *)ptr, sizes[run]); + if (!ptr || cur_mte_cxt.fault_valid == true) { + ksft_print_msg("FAIL: Insert tags on file based memory\n"); + munmap((void *)map_ptr, map_size); + close(fd); + return KSFT_FAIL; + } + result = check_child_tag_inheritance(ptr, sizes[run], mode); + mte_clear_tags((void *)ptr, sizes[run]); + munmap((void *)map_ptr, map_size); + close(fd); + if (result != KSFT_PASS) + return KSFT_FAIL; + } + return KSFT_PASS; +} + +int main(int argc, char *argv[]) +{ + int err; + int item = sizeof(sizes)/sizeof(int); + + page_size = getpagesize(); + if (!page_size) { + ksft_print_msg("ERR: Unable to get page size\n"); + return KSFT_FAIL; + } + sizes[item - 3] = page_size - 1; + sizes[item - 2] = page_size; + sizes[item - 1] = page_size + 1; + + err = mte_default_setup(); + if (err) + return err; + + /* Register SIGSEGV handler */ + mte_register_signal(SIGSEGV, mte_default_handler); + mte_register_signal(SIGBUS, mte_default_handler); + + evaluate_test(check_child_memory_mapping(USE_MMAP, MTE_SYNC_ERR, MAP_PRIVATE), + "Check child anonymous memory with private mapping, precise mode and mmap memory\n"); + evaluate_test(check_child_memory_mapping(USE_MMAP, MTE_SYNC_ERR, MAP_SHARED), + "Check child anonymous memory with shared mapping, precise mode and mmap memory\n"); + evaluate_test(check_child_memory_mapping(USE_MMAP, MTE_ASYNC_ERR, MAP_PRIVATE), + "Check child anonymous memory with private mapping, imprecise mode and mmap memory\n"); + evaluate_test(check_child_memory_mapping(USE_MMAP, MTE_ASYNC_ERR, MAP_SHARED), + "Check child anonymous memory with shared mapping, imprecise mode and mmap memory\n"); + evaluate_test(check_child_memory_mapping(USE_MPROTECT, MTE_SYNC_ERR, MAP_PRIVATE), + "Check child anonymous memory with private mapping, precise mode and mmap/mprotect memory\n"); + evaluate_test(check_child_memory_mapping(USE_MPROTECT, MTE_SYNC_ERR, MAP_SHARED), + "Check child anonymous memory with shared mapping, precise mode and mmap/mprotect memory\n"); + + evaluate_test(check_child_file_mapping(USE_MMAP, MTE_SYNC_ERR, MAP_PRIVATE), + "Check child file memory with private mapping, precise mode and mmap memory\n"); + evaluate_test(check_child_file_mapping(USE_MMAP, MTE_SYNC_ERR, MAP_SHARED), + "Check child file memory with shared mapping, precise mode and mmap memory\n"); + evaluate_test(check_child_memory_mapping(USE_MMAP, MTE_ASYNC_ERR, MAP_PRIVATE), + "Check child file memory with private mapping, imprecise mode and mmap memory\n"); + evaluate_test(check_child_memory_mapping(USE_MMAP, MTE_ASYNC_ERR, MAP_SHARED), + "Check child file memory with shared mapping, imprecise mode and mmap memory\n"); + evaluate_test(check_child_memory_mapping(USE_MPROTECT, MTE_SYNC_ERR, MAP_PRIVATE), + "Check child file memory with private mapping, precise mode and mmap/mprotect memory\n"); + evaluate_test(check_child_memory_mapping(USE_MPROTECT, MTE_SYNC_ERR, MAP_SHARED), + "Check child file memory with shared mapping, precise mode and mmap/mprotect memory\n"); + + mte_restore_setup(); + ksft_print_cnts(); + return ksft_get_fail_cnt() == 0 ? KSFT_PASS : KSFT_FAIL; +}

Add a testcase to check that KSM should not merge pages containing same data with same/different MTE tag values.

This testcase has one positive tests and passes if page merging happens according to the above rule. It also saves and restores any modified ksm sysfs entries.

Cc: Shuah Khan shuah@kernel.org Cc: Catalin Marinas catalin.marinas@arm.com Cc: Will Deacon will@kernel.org Signed-off-by: Amit Daniel Kachhap amit.kachhap@arm.com --- Changes in v2: * Moved read/write sysfs functions from global to local functions.

tools/testing/selftests/arm64/mte/.gitignore | 1 + .../selftests/arm64/mte/check_ksm_options.c | 159 ++++++++++++++++++ 2 files changed, 160 insertions(+) create mode 100644 tools/testing/selftests/arm64/mte/check_ksm_options.c

diff --git a/tools/testing/selftests/arm64/mte/.gitignore b/tools/testing/selftests/arm64/mte/.gitignore index 79a215d3bbd0..44e9bfdaeca6 100644 --- a/tools/testing/selftests/arm64/mte/.gitignore +++ b/tools/testing/selftests/arm64/mte/.gitignore @@ -2,3 +2,4 @@ check_buffer_fill check_tags_inclusion check_child_memory check_mmap_options +check_ksm_options diff --git a/tools/testing/selftests/arm64/mte/check_ksm_options.c b/tools/testing/selftests/arm64/mte/check_ksm_options.c new file mode 100644 index 000000000000..bc41ae630c86 --- /dev/null +++ b/tools/testing/selftests/arm64/mte/check_ksm_options.c @@ -0,0 +1,159 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2020 ARM Limited + +#define _GNU_SOURCE + +#include <errno.h> +#include <fcntl.h> +#include <signal.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <ucontext.h> +#include <sys/mman.h> + +#include "kselftest.h" +#include "mte_common_util.h" +#include "mte_def.h" + +#define TEST_UNIT 10 +#define PATH_KSM "/sys/kernel/mm/ksm/" +#define MAX_LOOP 4 + +static size_t page_sz; +static unsigned long ksm_sysfs[5]; + +static unsigned long read_sysfs(char *str) +{ + FILE *f; + unsigned long val = 0; + + f = fopen(str, "r"); + if (!f) { + ksft_print_msg("ERR: missing %s\n", str); + return 0; + } + fscanf(f, "%lu", &val); + fclose(f); + return val; +} + +static void write_sysfs(char *str, unsigned long val) +{ + FILE *f; + + f = fopen(str, "w"); + if (!f) { + ksft_print_msg("ERR: missing %s\n", str); + return; + } + fprintf(f, "%lu", val); + fclose(f); +} + +static void mte_ksm_setup(void) +{ + ksm_sysfs[0] = read_sysfs(PATH_KSM "merge_across_nodes"); + write_sysfs(PATH_KSM "merge_across_nodes", 1); + ksm_sysfs[1] = read_sysfs(PATH_KSM "sleep_millisecs"); + write_sysfs(PATH_KSM "sleep_millisecs", 0); + ksm_sysfs[2] = read_sysfs(PATH_KSM "run"); + write_sysfs(PATH_KSM "run", 1); + ksm_sysfs[3] = read_sysfs(PATH_KSM "max_page_sharing"); + write_sysfs(PATH_KSM "max_page_sharing", ksm_sysfs[3] + TEST_UNIT); + ksm_sysfs[4] = read_sysfs(PATH_KSM "pages_to_scan"); + write_sysfs(PATH_KSM "pages_to_scan", ksm_sysfs[4] + TEST_UNIT); +} + +static void mte_ksm_restore(void) +{ + write_sysfs(PATH_KSM "merge_across_nodes", ksm_sysfs[0]); + write_sysfs(PATH_KSM "sleep_millisecs", ksm_sysfs[1]); + write_sysfs(PATH_KSM "run", ksm_sysfs[2]); + write_sysfs(PATH_KSM "max_page_sharing", ksm_sysfs[3]); + write_sysfs(PATH_KSM "pages_to_scan", ksm_sysfs[4]); +} + +static void mte_ksm_scan(void) +{ + int cur_count = read_sysfs(PATH_KSM "full_scans"); + int scan_count = cur_count + 1; + int max_loop_count = MAX_LOOP; + + while ((cur_count < scan_count) && max_loop_count) { + sleep(1); + cur_count = read_sysfs(PATH_KSM "full_scans"); + max_loop_count--; + } +#ifdef DEBUG + ksft_print_msg("INFO: pages_shared=%lu pages_sharing=%lu\n", + read_sysfs(PATH_KSM "pages_shared"), + read_sysfs(PATH_KSM "pages_sharing")); +#endif +} + +static int check_madvise_options(int mem_type, int mode, int mapping) +{ + char *ptr; + int err, ret; + + err = KSFT_FAIL; + if (access(PATH_KSM, F_OK) == -1) { + ksft_print_msg("ERR: Kernel KSM config not enabled\n"); + return err; + } + + mte_switch_mode(mode, MTE_ALLOW_NON_ZERO_TAG); + ptr = mte_allocate_memory(TEST_UNIT * page_sz, mem_type, mapping, true); + if (check_allocated_memory(ptr, TEST_UNIT * page_sz, mem_type, false) != KSFT_PASS) + return KSFT_FAIL; + + /* Insert same data in all the pages */ + memset(ptr, 'A', TEST_UNIT * page_sz); + ret = madvise(ptr, TEST_UNIT * page_sz, MADV_MERGEABLE); + if (ret) { + ksft_print_msg("ERR: madvise failed to set MADV_UNMERGEABLE\n"); + goto madvise_err; + } + mte_ksm_scan(); + /* Tagged pages should not merge */ + if ((read_sysfs(PATH_KSM "pages_shared") < 1) || + (read_sysfs(PATH_KSM "pages_sharing") < (TEST_UNIT - 1))) + err = KSFT_PASS; +madvise_err: + mte_free_memory(ptr, TEST_UNIT * page_sz, mem_type, true); + return err; +} + +int main(int argc, char *argv[]) +{ + int err; + + err = mte_default_setup(); + if (err) + return err; + page_sz = getpagesize(); + if (!page_sz) { + ksft_print_msg("ERR: Unable to get page size\n"); + return KSFT_FAIL; + } + /* Register signal handlers */ + mte_register_signal(SIGBUS, mte_default_handler); + mte_register_signal(SIGSEGV, mte_default_handler); + /* Enable KSM */ + mte_ksm_setup(); + + evaluate_test(check_madvise_options(USE_MMAP, MTE_SYNC_ERR, MAP_PRIVATE), + "Check KSM mte page merge for private mapping, sync mode and mmap memory\n"); + evaluate_test(check_madvise_options(USE_MMAP, MTE_ASYNC_ERR, MAP_PRIVATE), + "Check KSM mte page merge for private mapping, async mode and mmap memory\n"); + evaluate_test(check_madvise_options(USE_MMAP, MTE_SYNC_ERR, MAP_SHARED), + "Check KSM mte page merge for shared mapping, sync mode and mmap memory\n"); + evaluate_test(check_madvise_options(USE_MMAP, MTE_ASYNC_ERR, MAP_SHARED), + "Check KSM mte page merge for shared mapping, async mode and mmap memory\n"); + + mte_ksm_restore(); + mte_restore_setup(); + ksft_print_cnts(); + return ksft_get_fail_cnt() == 0 ? KSFT_PASS : KSFT_FAIL; +}