[PATCH 2/6] kselftest/arm64: Verify mte tag inclusion via prctl
Amit Daniel Kachhap
amit.kachhap at arm.com
Tue Sep 1 05:27:15 EDT 2020
This testcase verifies that the tag generated with "irg" instruction
contains only included tags. This is done via prtcl call.
This test covers 4 scenarios,
* At least one included tag.
* More than one included tags.
* None included.
* All included.
Cc: Shuah Khan <shuah at kernel.org>
Cc: Catalin Marinas <catalin.marinas at arm.com>
Cc: Will Deacon <will at kernel.org>
Co-developed-by: Gabor Kertesz <gabor.kertesz at arm.com>
Signed-off-by: Gabor Kertesz <gabor.kertesz at arm.com>
Signed-off-by: Amit Daniel Kachhap <amit.kachhap at arm.com>
---
tools/testing/selftests/arm64/mte/.gitignore | 1 +
.../arm64/mte/check_tags_inclusion.c | 183 ++++++++++++++++++
2 files changed, 184 insertions(+)
create mode 100644 tools/testing/selftests/arm64/mte/check_tags_inclusion.c
diff --git a/tools/testing/selftests/arm64/mte/.gitignore b/tools/testing/selftests/arm64/mte/.gitignore
index 3f8c1f6c82b9..c3fca255d3d6 100644
--- a/tools/testing/selftests/arm64/mte/.gitignore
+++ b/tools/testing/selftests/arm64/mte/.gitignore
@@ -1 +1,2 @@
check_buffer_fill
+check_tags_inclusion
diff --git a/tools/testing/selftests/arm64/mte/check_tags_inclusion.c b/tools/testing/selftests/arm64/mte/check_tags_inclusion.c
new file mode 100644
index 000000000000..9614988e2e75
--- /dev/null
+++ b/tools/testing/selftests/arm64/mte/check_tags_inclusion.c
@@ -0,0 +1,183 @@
+// 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 * 2)
+#define MTE_LAST_TAG_MASK (0x7FFF)
+
+static int verify_mte_pointer_validity(char *ptr, int mode)
+{
+ mte_initialize_current_context(mode, (uintptr_t)ptr, BUFFER_SIZE);
+ /* Check the validity of the tagged pointer */
+ memset((void *)ptr, '1', BUFFER_SIZE);
+ mte_wait_after_trig();
+ if (cur_mte_cxt.fault_valid)
+ return KSFT_FAIL;
+ /* Proceed further for nonzero tags */
+ if (!MT_FETCH_TAG((uintptr_t)ptr))
+ return KSFT_PASS;
+ mte_initialize_current_context(mode, (uintptr_t)ptr, BUFFER_SIZE + 1);
+ /* Check the validity outside the range */
+ ptr[BUFFER_SIZE] = '2';
+ mte_wait_after_trig();
+ if (!cur_mte_cxt.fault_valid)
+ return KSFT_FAIL;
+ else
+ return KSFT_PASS;
+}
+
+static int check_single_included_tags(int mem_type, int mode)
+{
+ char *ptr;
+ int tag, run, result = KSFT_PASS;
+
+ ptr = (char *)mte_allocate_memory(BUFFER_SIZE + MT_GRANULE_SIZE, mem_type, 0, false);
+ if (check_allocated_memory(ptr, BUFFER_SIZE + MT_GRANULE_SIZE,
+ mem_type, false) != KSFT_PASS)
+ return KSFT_FAIL;
+
+ for (tag = 0; (tag < MT_TAG_COUNT) && (result == KSFT_PASS); tag++) {
+ mte_switch_mode(mode, MT_INCLUDE_VALID_TAG(tag));
+ /* Try to catch a excluded tag by a number of tries. */
+ for (run = 0; (run < RUNS) && (result == KSFT_PASS); run++) {
+ ptr = (char *)mte_insert_tags(ptr, BUFFER_SIZE);
+ /* Check tag value */
+ if (MT_FETCH_TAG((uintptr_t)ptr) == tag) {
+ ksft_print_msg("FAIL: wrong tag = 0x%x with include mask=0x%x\n",
+ MT_FETCH_TAG((uintptr_t)ptr),
+ MT_INCLUDE_VALID_TAG(tag));
+ result = KSFT_FAIL;
+ break;
+ }
+ result = verify_mte_pointer_validity(ptr, mode);
+ }
+ }
+ mte_free_memory_tag_range((void *)ptr, BUFFER_SIZE, mem_type, 0, MT_GRANULE_SIZE);
+ return result;
+}
+
+static int check_multiple_included_tags(int mem_type, int mode)
+{
+ char *ptr;
+ int tag, run, result = KSFT_PASS;
+ unsigned long excl_mask = 0;
+
+ ptr = (char *)mte_allocate_memory(BUFFER_SIZE + MT_GRANULE_SIZE, mem_type, 0, false);
+ if (check_allocated_memory(ptr, BUFFER_SIZE + MT_GRANULE_SIZE,
+ mem_type, false) != KSFT_PASS)
+ return KSFT_FAIL;
+
+ for (tag = 0; (tag < MT_TAG_COUNT - 1) && (result == KSFT_PASS); tag++) {
+ excl_mask |= 1 << tag;
+ mte_switch_mode(mode, MT_INCLUDE_VALID_TAGS(excl_mask));
+ /* Try to catch a excluded tag by a number of tries. */
+ for (run = 0; (run < RUNS) && (result == KSFT_PASS); run++) {
+ /* If excl_mask is all except last then clear tag for the next loop */
+ if (excl_mask == MTE_LAST_TAG_MASK && run)
+ ptr = (char *)MT_CLEAR_TAG((unsigned long)ptr);
+ ptr = (char *)mte_insert_tags(ptr, BUFFER_SIZE);
+ /* Check tag value */
+ if (MT_FETCH_TAG((uintptr_t)ptr) < tag) {
+ ksft_print_msg("FAIL: wrong tag = 0x%x with include mask=0x%x\n",
+ MT_FETCH_TAG((uintptr_t)ptr),
+ MT_INCLUDE_VALID_TAGS(excl_mask));
+ result = KSFT_FAIL;
+ break;
+ }
+ result = verify_mte_pointer_validity(ptr, mode);
+ }
+ }
+ mte_free_memory_tag_range((void *)ptr, BUFFER_SIZE, mem_type, 0, MT_GRANULE_SIZE);
+ return result;
+}
+
+static int check_all_included_tags(int mem_type, int mode)
+{
+ char *ptr;
+ int run, result = KSFT_PASS;
+
+ ptr = (char *)mte_allocate_memory(BUFFER_SIZE + MT_GRANULE_SIZE, mem_type, 0, false);
+ if (check_allocated_memory(ptr, BUFFER_SIZE + MT_GRANULE_SIZE,
+ mem_type, false) != KSFT_PASS)
+ return KSFT_FAIL;
+
+ mte_switch_mode(mode, MT_INCLUDE_TAG_MASK);
+ /* Try to catch a excluded tag by a number of tries. */
+ for (run = 0; (run < RUNS) && (result == KSFT_PASS); run++) {
+ ptr = (char *)mte_insert_tags(ptr, BUFFER_SIZE);
+ /*
+ * Here tag byte can be between 0x0 to 0xF so no need to match so
+ * just verify if it is writable.
+ */
+ result = verify_mte_pointer_validity(ptr, mode);
+ }
+ mte_free_memory_tag_range((void *)ptr, BUFFER_SIZE, mem_type, 0, MT_GRANULE_SIZE);
+ return result;
+}
+
+static int check_none_included_tags(int mem_type, int mode)
+{
+ char *ptr;
+
+ ptr = (char *)mte_allocate_memory(BUFFER_SIZE, mem_type, 0, false);
+ if (check_allocated_memory(ptr, BUFFER_SIZE, mem_type, false) != KSFT_PASS)
+ return KSFT_FAIL;
+
+ mte_switch_mode(mode, 0);
+ ptr = (char *)mte_insert_tags(ptr, BUFFER_SIZE);
+ /* Check tag value */
+ if (MT_FETCH_TAG((uintptr_t)ptr)) {
+ ksft_print_msg("FAIL: included tag value found\n");
+ return KSFT_FAIL;
+ }
+ mte_initialize_current_context(mode, (uintptr_t)ptr, BUFFER_SIZE);
+ /* Check the write validity of the untagged pointer */
+ memset((void *)ptr, '1', BUFFER_SIZE);
+ mte_wait_after_trig();
+ if (cur_mte_cxt.fault_valid)
+ return KSFT_FAIL;
+ else
+ return KSFT_PASS;
+}
+
+int main(int argc, char *argv[])
+{
+ int err;
+
+ err = mte_default_setup();
+ if (err)
+ return err;
+
+ /* Register SIGSEGV handler */
+ mte_register_signal(SIGSEGV, mte_default_handler);
+
+ evaluate_test(check_single_included_tags(USE_MMAP, MTE_SYNC_ERR),
+ "Check an included tag value with sync mode\n");
+
+ evaluate_test(check_multiple_included_tags(USE_MMAP, MTE_SYNC_ERR),
+ "Check different included tags value with sync mode\n");
+
+ evaluate_test(check_none_included_tags(USE_MMAP, MTE_SYNC_ERR),
+ "Check none included tags value with sync mode\n");
+
+ evaluate_test(check_all_included_tags(USE_MMAP, MTE_SYNC_ERR),
+ "Check all included tags value with sync mode\n");
+
+ mte_restore_setup();
+ ksft_print_cnts();
+ return ksft_get_fail_cnt() == 0 ? KSFT_PASS : KSFT_FAIL;
+}
--
2.17.1
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