/*
* Copyright (c) 2024 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. The rights granted to you under the License
* may not be used to create, or enable the creation or redistribution of,
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
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*
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
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*/
/*
* try_read_write_test_unexpected.c
*
* Test the testing helper functions in try_read_write.h.
* The exception handler used by try_read_byte/try_write_byte
* should allow other exceptions to continue to a crash.
*/
#include <stdint.h>
#include <stdbool.h>
#include <darwintest.h>
#include <sys/wait.h>
#include <mach/mach.h>
#include <mach/mach_vm.h>
#include "try_read_write.h"
T_GLOBAL_META(
T_META_NAMESPACE("xnu"),
T_META_RADAR_COMPONENT_NAME("xnu"),
T_META_RADAR_COMPONENT_VERSION("vm"),
T_META_RUN_CONCURRENTLY(true),
T_META_ALL_VALID_ARCHS(true),
/* these tests are expected to crash */
T_META_IGNORECRASHES(".*try_read_write_test_unexpected.*")
);
static void
install_exception_handler(void)
{
kern_return_t kr;
bool result;
result = try_write_byte(0, 0, &kr);
T_QUIET; T_ASSERT_EQ(result, false, "try_write_byte to NULL");
T_QUIET; T_ASSERT_EQ(kr, KERN_INVALID_ADDRESS, "try_write_byte to NULL");
}
static void
test_crasher(void (^crashing_block)(void))
{
pid_t child_pid;
if ((child_pid = fork())) {
/* parent */
int status;
int err = waitpid(child_pid, &status, 0);
T_QUIET; T_ASSERT_POSIX_SUCCESS(err, "waitpid");
T_EXPECT_TRUE(WIFSIGNALED(status), "parent: child process should crash");
} else {
/* child */
T_LOG("-- Calling try_write_byte() to install exception handlers --");
install_exception_handler();
T_LOG("-- The next exception should crash --");
crashing_block();
T_FAIL("child: process should have crashed");
}
}
static void __attribute__((noinline))
THIS_IS_EXPECTED_TO_CRASH_EXC_BAD_ACCESS(void)
{
*(volatile int *)0 = 1;
}
static void __attribute__((noinline))
THIS_IS_EXPECTED_TO_CRASH_BUILTIN_TRAP(void)
{
__builtin_trap();
}
T_DECL(try_read_write_unexpected_bad_access,
"test an unrelated EXC_BAD_ACCESS exception "
"with the try_read_write exception handler in place")
{
test_crasher(^{
/*
* Provoke EXC_BAD_ACCESS outside try_read_byte and try_write_byte.
* The try_read_write exception handler should catch and rethrow it.
*/
THIS_IS_EXPECTED_TO_CRASH_EXC_BAD_ACCESS();
});
}
T_DECL(try_read_write_unexpected_trap,
"test an unrelated non-EXC_BAD_ACCESS exception "
"with the try_read_write exception handler in place")
{
test_crasher(^{
/*
* Provoke a non-EXC_BAD_ACCESS exception outside of try_read_byte and try_write_byte.
* The try_read_write exception handler should not catch it.
*/
THIS_IS_EXPECTED_TO_CRASH_BUILTIN_TRAP();
});
}