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tests/memorystatus_vm_map_fork.c xnu-12377.101.15 /dev/null
--- xnu/xnu-12377.101.15/tests/memorystatus_vm_map_fork.c
+++ /dev/null
@@ -1,485 +0,0 @@
-#include <stdio.h>
-#include <unistd.h>
-#include <stdlib.h>
-#include <errno.h>
-#include <string.h>
-#include <assert.h>
-#include <signal.h>
-#include <spawn.h>
-#include <spawn_private.h>
-#include <stdint.h>
-#include <sys/sysctl.h>
-#include <sys/spawn_internal.h>
-#include <sys/kern_memorystatus.h>
-#include <mach-o/dyld.h>
-
-#include <darwintest.h>
-#include <darwintest_utils.h>
-
-#include "test_utils.h"
-
-T_GLOBAL_META(
-	T_META_NAMESPACE("xnu.vm"),
-	T_META_RADAR_COMPONENT_NAME("xnu"),
-	T_META_RADAR_COMPONENT_VERSION("VM"),
-	T_META_CHECK_LEAKS(false)
-	);
-
-extern char **environ;
-
-/*
- * This test file contains two sub-tests which attempt to verify
- * the allowing or not allowing of a corpse for crashreporter when
- * a task exceeds its memory allocation limit. vm_map_fork() is the
- * kernel routine used to generate a corpse task.
- *
- * A corpse is allowed to be taken if a task's memory resource limit that
- * is exceeded is less than 1/4 of the system wide task limit.
- * If the amount exceeds 1/4 the sytem wide limit, then the corpse is disallowed.
- *
- * If the device under test is already under pressure, the test
- * could fail due to jetsam cutting in and killing the parent, child or
- * other necessary testing processes.
- */
-
-/* Test variants */
-#define TEST_ALLOWED     0x1
-#define TEST_NOT_ALLOWED 0x2
-
-/*
- * Values which the kernel OR's into the PID when a corpse
- * is either allowed or disallowed for the
- * kern.memorystatus_vm_map_fork_pidwatch sysctl.
- */
-#define MEMORYSTATUS_VM_MAP_FORK_ALLOWED        0x100000000ul
-#define MEMORYSTATUS_VM_MAP_FORK_NOT_ALLOWED 0x200000000ul
-
-/*
- * The memory allocation happens in a child process, this
- * is stuff to deal with creating and managing the child.
- * The child will only execute the T_HELPER_DECL.
- */
-static char testpath[PATH_MAX];
-static uint32_t testpath_size = sizeof(testpath);
-#define LIMIT_DELTA_MB 5 /* an arbitrary limit delta */
-#define MEGABYTE        (1024 * 1024)
-
-/*
- * The child process communicates back to parent via an exit() code.
- */
-enum child_exits {
-	NORMAL_EXIT = 0,
-	NO_MEMSIZE_ARG,
-	INVALID_MEMSIZE,
-	MALLOC_FAILED,
-	NUM_CHILD_EXIT
-};
-static char *child_exit_why[] = {
-	"normal exit",
-	"no memsize argument to child",
-	"invalid memsize argument to child",
-	"malloc() failed",
-};
-
-/*
- * Set/Get the sysctl used to determine if corpse collection occurs.
- * This is done by the kernel checking for a specific PID.
- */
-static void
-set_memorystatus_vm_map_fork_pidwatch(pid_t pid)
-{
-	uint64_t new_value = (uint64_t)pid;
-	size_t new_len = sizeof(new_value);
-	int err;
-
-	err = sysctlbyname("kern.memorystatus_vm_map_fork_pidwatch", NULL, NULL, &new_value, new_len);
-	T_QUIET;
-	T_ASSERT_POSIX_SUCCESS(err, "set sysctlbyname(kern.memorystatus_vm_map_fork_pidwatch...) failed");
-	return;
-}
-
-static uint64_t
-get_memorystatus_vm_map_fork_pidwatch()
-{
-	uint64_t value = 0;
-	size_t val_len = sizeof(value);
-	int err;
-
-	err = sysctlbyname("kern.memorystatus_vm_map_fork_pidwatch", &value, &val_len, NULL, 0);
-	T_QUIET;
-	T_ASSERT_POSIX_SUCCESS(err, "get sysctlbyname(kern.memorystatus_vm_map_fork_pidwatch...) failed");
-
-	return value;
-}
-
-/*
- * We want to avoid jetsam giving us bad results, if possible. So check if there's
- * enough memory for the test to run, waiting briefly for some to free up.
- */
-static void
-wait_for_free_mem(int need_mb)
-{
-	int64_t         memsize;
-	int             memorystatus_level;
-	size_t          size;
-	int64_t         avail;
-	int             err;
-	int             try;
-
-	/*
-	 * get amount of memory in the machine
-	 */
-	size = sizeof(memsize);
-	err = sysctlbyname("hw.memsize", &memsize, &size, NULL, 0);
-	T_QUIET; T_ASSERT_POSIX_SUCCESS(err, "sysctlbyname(hw.memsize...) failed");
-
-	/*
-	 * Use a loop to briefly sleep and recheck if short on memory.
-	 */
-	try = 1;
-	for (;;) {
-		/*
-		 * memorystatus_level is a percentage of memory available. For example 20 means 1/5 of memory.
-		 * It currently doesn't exist on macOS but neither does jetsam, so pass the test there.
-		 */
-		size = sizeof(memorystatus_level);
-		if (sysctlbyname("kern.memorystatus_level", &memorystatus_level, &size, NULL, 0) != 0) {
-			return;
-		}
-		T_QUIET; T_ASSERT_LE(memorystatus_level, 100, "memorystatus_level too high");
-		T_QUIET; T_ASSERT_GT(memorystatus_level, 0, "memorystatus_level negative");
-
-		/*
-		 * jetsam kicks in at memory status level of 15%, so subtract that much out of what's available.
-		 */
-		avail = MAX(0, (memsize * (memorystatus_level - 15)) / 100);
-
-		/*
-		 * We're good to go if there's more than enough available.
-		 */
-		if ((int64_t)need_mb * MEGABYTE < avail) {
-			return;
-		}
-
-		/*
-		 * issue a message to log and sleep briefly to see if we can get more memory
-		 */
-		if (try-- == 0) {
-			break;
-		}
-		T_LOG("Need %d MB, only %d MB available. sleeping 5 seconds for more to free. memorystatus_level %d",
-		    need_mb, (int)(avail / MEGABYTE), memorystatus_level);
-		sleep(5);
-	}
-	T_SKIP("Needed %d MB, but only %d MB available. Skipping test to avoid jetsam issues.",
-	    need_mb, (int)(avail / MEGABYTE));
-}
-
-
-/*
- * The main test calls this to spawn child process which will run and
- * exceed some memory limit. The child is initially suspended so that
- * we can do the sysctl calls before it runs.
- * Since this is a libdarwintest, the "-n" names the T_HELPER_DECL() that
- * we want to run. The arguments specific to the test follow a "--".
- */
-static pid_t
-spawn_child_process(
-	char * const executable,
-	char * const memlimit,
-	short flags,
-	int priority,
-	int active_limit_mb,
-	int inactive_limit_mb)
-{
-	posix_spawnattr_t spawn_attrs;
-	int err;
-	pid_t child_pid;
-	char * const argv_child[] = { executable, "-n", "child_process", "--", memlimit, NULL };
-
-	err = posix_spawnattr_init(&spawn_attrs);
-	T_QUIET; T_ASSERT_POSIX_SUCCESS(err, "  posix_spawnattr_init() failed");
-
-	err = posix_spawnattr_setflags(&spawn_attrs, POSIX_SPAWN_START_SUSPENDED);
-	T_QUIET; T_ASSERT_POSIX_SUCCESS(err, "  posix_spawnattr_setflags() failed");
-
-	err = posix_spawnattr_setjetsam_ext(&spawn_attrs, flags, priority, active_limit_mb, inactive_limit_mb);
-	T_QUIET; T_ASSERT_POSIX_SUCCESS(err, "  posix_spawnattr_setjetsam_ext() failed");
-
-	err = posix_spawn(&child_pid, executable, NULL, &spawn_attrs, argv_child, environ);
-	T_QUIET; T_ASSERT_POSIX_SUCCESS(err, "  posix_spawn() failed");
-
-	return child_pid;
-}
-
-
-/*
- * The parent calls this to continue the suspended child, then wait for its result.
- * We collect its resource usage to vefiry the expected amount allocated.
- */
-static void
-test_child_process(pid_t child_pid, int *status, struct rusage *ru)
-{
-	int err = 0;
-	pid_t got_pid;
-
-	T_LOG("  continuing child[%d]\n", child_pid);
-
-	err = kill(child_pid, SIGCONT);
-	T_QUIET; T_ASSERT_POSIX_SUCCESS(err, "  kill(%d, SIGCONT) failed", child_pid);
-
-	T_LOG("  waiting for child[%d] to exit", child_pid);
-
-	got_pid = wait4(child_pid, status, 0, ru);
-	T_QUIET; T_ASSERT_EQ(child_pid, got_pid, "  wait4(%d, ...) returned %d", child_pid, got_pid);
-}
-
-/*
- * The child process executes this code. The easiest way, with given darwintest infrastructure,
- * it has to return information is via exit status.
- */
-T_HELPER_DECL(child_process, "child allocates memory to failure")
-{
-#define BYTESPERALLOC   MEGABYTE
-#define BYTESINEXCESS   (2 * MEGABYTE) /* 2 MB - arbitrary */
-	char *limit;
-	long limit_mb = 0;
-	long max_bytes_to_munch, bytes_remaining, bytes_this_munch;
-	void *mem = NULL;
-
-	/*
-	 * This helper is run in a child process. The helper sees one argument
-	 * as a string which is the amount of memory in megabytes to allocate.
-	 */
-	if (argc != 1) {
-		exit(NO_MEMSIZE_ARG);
-	}
-
-	limit = argv[0];
-	errno = 0;
-	limit_mb = strtol(limit, NULL, 10);
-	if (errno != 0 || limit_mb <= 0) {
-		exit(INVALID_MEMSIZE);
-	}
-
-	/* Compute in excess of assigned limit */
-	max_bytes_to_munch = limit_mb * MEGABYTE;
-	max_bytes_to_munch += BYTESINEXCESS;
-
-	for (bytes_remaining = max_bytes_to_munch; bytes_remaining > 0; bytes_remaining -= bytes_this_munch) {
-		bytes_this_munch = MIN(bytes_remaining, BYTESPERALLOC);
-
-		mem = malloc((size_t)bytes_this_munch);
-		if (mem == NULL) {
-			exit(MALLOC_FAILED);
-		}
-		arc4random_buf(mem, (size_t)bytes_this_munch);
-	}
-
-	/* We chewed up all the memory we were asked to. */
-	exit(NORMAL_EXIT);
-}
-
-
-/*
- * Actual test body.
- */
-static void
-memorystatus_vm_map_fork_parent(int test_variant)
-{
-	int             max_task_pmem = 0; /* MB */
-	size_t          size = 0;
-	int             active_limit_mb = 0;
-	int             inactive_limit_mb = 0;
-	short           flags = 0;
-	char            memlimit_str[16];
-	pid_t           child_pid;
-	int             child_status;
-	uint64_t        kernel_pidwatch_val;
-	uint64_t        expected_pidwatch_val;
-	int             ret;
-	struct rusage   ru;
-	enum child_exits exit_val;
-
-	/*
-	 * The code to set/get the pidwatch sysctl is only in
-	 * development kernels. Skip the test if not on one.
-	 */
-	if (!is_development_kernel()) {
-		T_SKIP("Can't test on release kernel");
-	}
-
-	/*
-	 * Determine a memory limit based on system having one or not.
-	 */
-	size = sizeof(max_task_pmem);
-	(void)sysctlbyname("kern.max_task_pmem", &max_task_pmem, &size, NULL, 0);
-	if (max_task_pmem <= 0) {
-		max_task_pmem = 0;
-	}
-
-	/* default limit is 1/4 of max task phys memory value */
-	active_limit_mb = max_task_pmem / 4;
-
-#if TARGET_OS_WATCH
-
-	/*
-	 * Larger memory watches have a raised corpse size limit.
-	 * One coprse of 300Meg is allowed, others are 200M.
-	 * We pick 300 or 200 based on which test is being done.
-	 */
-	uint64_t hw_memsize = 0;
-	size = sizeof(hw_memsize);
-	T_ASSERT_POSIX_SUCCESS(sysctlbyname("hw.memsize", &hw_memsize, &size, NULL, 0), "read hw.memsize");
-	if (hw_memsize > 1024 * 1024 * 1024) {
-		if (test_variant == TEST_ALLOWED) {
-			active_limit_mb = MAX(active_limit_mb, 200);
-		} else {
-			active_limit_mb = MAX(active_limit_mb, 300);
-		}
-	}
-
-#endif /* TARGET_OS_WATCH */
-
-	if (test_variant == TEST_ALLOWED) {
-		/*
-		 * Tell the child to allocate less than 1/4 the system wide limit.
-		 */
-		if (active_limit_mb <= LIMIT_DELTA_MB) {
-			active_limit_mb = LIMIT_DELTA_MB;
-		} else {
-			active_limit_mb -= LIMIT_DELTA_MB;
-		}
-		expected_pidwatch_val = MEMORYSTATUS_VM_MAP_FORK_ALLOWED;
-	} else { /* TEST_NOT_ALLOWED */
-		/*
-		 * Tell the child to allocate more than 1/4 the system wide limit.
-		 */
-		active_limit_mb += LIMIT_DELTA_MB;
-		if (max_task_pmem == 0) {
-			expected_pidwatch_val = MEMORYSTATUS_VM_MAP_FORK_ALLOWED;
-		} else {
-			expected_pidwatch_val = MEMORYSTATUS_VM_MAP_FORK_NOT_ALLOWED;
-		}
-	}
-	inactive_limit_mb = active_limit_mb;
-	T_LOG("using limit of %d Meg", active_limit_mb);
-
-	/*
-	 * When run as part of a larger suite, a previous test
-	 * may have left the system temporarily with too little
-	 * memory to run this test. We try to detect if there is
-	 * enough free memory to proceed, waiting a little bit
-	 * for memory to free up.
-	 */
-	wait_for_free_mem(active_limit_mb);
-
-#if TARGET_OS_OSX
-	/*
-	 * vm_map_fork() is always allowed on desktop.
-	 */
-	expected_pidwatch_val = MEMORYSTATUS_VM_MAP_FORK_ALLOWED;
-#endif
-
-	/*
-	 * Prepare the arguments needed to spawn the child process.
-	 */
-	memset(memlimit_str, 0, sizeof(memlimit_str));
-	(void)sprintf(memlimit_str, "%d", active_limit_mb);
-
-	ret = _NSGetExecutablePath(testpath, &testpath_size);
-	T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "_NSGetExecutablePath(%s, ...)", testpath);
-
-	/*
-	 * We put the child process in FOREGROUND to try and keep jetsam's hands off it.
-	 */
-	child_pid = spawn_child_process(testpath, memlimit_str, flags,
-	    JETSAM_PRIORITY_FOREGROUND, active_limit_mb, inactive_limit_mb);
-
-	expected_pidwatch_val |= (uint64_t)child_pid;
-
-	/*
-	 * We only reach here if parent successfully spawned child process.
-	 */
-	T_LOG("  spawned child_pid[%d] with memlimit %s (%d)MB\n",
-	    child_pid, memlimit_str, active_limit_mb);
-
-	/*
-	 * Set the kernel's pidwatch to look for the child.
-	 */
-	(void)set_memorystatus_vm_map_fork_pidwatch((pid_t)0);
-	(void)set_memorystatus_vm_map_fork_pidwatch(child_pid);
-
-	/*
-	 * Let the child run and wait for it to finish.
-	 */
-	test_child_process(child_pid, &child_status, &ru);
-	T_LOG("Child exited with max_rss of %ld", ru.ru_maxrss);
-
-	/*
-	 * Retrieve the kernel's pidwatch value. This should now indicate
-	 * if the corpse was allowed or not.
-	 */
-	kernel_pidwatch_val = get_memorystatus_vm_map_fork_pidwatch();
-	(void)set_memorystatus_vm_map_fork_pidwatch((pid_t)0);
-
-	/*
-	 * If the child died abnormally, the test is invalid.
-	 */
-	if (!WIFEXITED(child_status)) {
-		if (WIFSIGNALED(child_status)) {
-			/* jetsam kills a process with SIGKILL */
-			if (WTERMSIG(child_status) == SIGKILL) {
-				T_LOG("Child appears to have been a jetsam victim");
-			}
-			T_SKIP("Child terminated by signal %d test result invalid", WTERMSIG(child_status));
-		}
-		T_SKIP("child did not exit normally (status=%d) test result invalid", child_status);
-	}
-
-	/*
-	 * We don't expect the child to exit for any other reason than success
-	 */
-	exit_val = (enum child_exits)WEXITSTATUS(child_status);
-	T_QUIET; T_ASSERT_EQ(exit_val, NORMAL_EXIT, "child exit due to: %s",
-	    (0 < exit_val && exit_val < NUM_CHILD_EXIT) ? child_exit_why[exit_val] : "unknown");
-
-	/*
-	 * If the kernel aborted generating a corpse for other reasons, the test is invalid.
-	 */
-	if (kernel_pidwatch_val == -1ull) {
-		T_SKIP("corpse generation was aborted by kernel");
-	}
-
-	/*
-	 * We should always have made it through the vm_map_fork() checks in the kernel for this test.
-	 */
-	T_QUIET; T_ASSERT_NE_ULLONG(kernel_pidwatch_val, (uint64_t)child_pid, "child didn't trigger corpse generation");
-
-	T_EXPECT_EQ(kernel_pidwatch_val, expected_pidwatch_val, "kernel value 0x%llx - expected 0x%llx",
-	    kernel_pidwatch_val, expected_pidwatch_val);
-}
-
-/*
- * The order of these 2 test functions is important. They will be executed by the test framwork in order.
- *
- * We test "not allowed first", then "allowed". If it were the other way around, the corpse from the "allowed"
- * test would likely cause memory pressure and jetsam would likely kill the "not allowed" test.
- */
-T_DECL(memorystatus_vm_map_fork_test_not_allowed,
-    "test that corpse generation was not allowed",
-    T_META_ASROOT(true),
-    T_META_TAG_VM_PREFERRED,
-    T_META_ENABLED(false /* rdar://133953771 */))
-{
-	memorystatus_vm_map_fork_parent(TEST_NOT_ALLOWED);
-}
-
-T_DECL(memorystatus_vm_map_fork_test_allowed,
-    "test corpse generation allowed",
-    T_META_ASROOT(true),
-    T_META_TAG_VM_PREFERRED,
-    T_META_ENABLED(false /* rdar://133953771 */))
-{
-	memorystatus_vm_map_fork_parent(TEST_ALLOWED);
-}