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- #define _GNU_SOURCE
- #define __EXPORTED_HEADERS__
- #include <errno.h>
- #include <inttypes.h>
- #include <limits.h>
- #include <linux/falloc.h>
- #include <linux/fcntl.h>
- #include <linux/memfd.h>
- #include <sched.h>
- #include <stdio.h>
- #include <stdlib.h>
- #include <signal.h>
- #include <string.h>
- #include <sys/mman.h>
- #include <sys/stat.h>
- #include <sys/syscall.h>
- #include <unistd.h>
- #define MFD_DEF_SIZE 8192
- #define STACK_SIZE 65535
- static int sys_memfd_create(const char *name,
- unsigned int flags)
- {
- return syscall(__NR_memfd_create, name, flags);
- }
- static int mfd_assert_new(const char *name, loff_t sz, unsigned int flags)
- {
- int r, fd;
- fd = sys_memfd_create(name, flags);
- if (fd < 0) {
- printf("memfd_create(\"%s\", %u) failed: %m\n",
- name, flags);
- abort();
- }
- r = ftruncate(fd, sz);
- if (r < 0) {
- printf("ftruncate(%llu) failed: %m\n", (unsigned long long)sz);
- abort();
- }
- return fd;
- }
- static void mfd_fail_new(const char *name, unsigned int flags)
- {
- int r;
- r = sys_memfd_create(name, flags);
- if (r >= 0) {
- printf("memfd_create(\"%s\", %u) succeeded, but failure expected\n",
- name, flags);
- close(r);
- abort();
- }
- }
- static __u64 mfd_assert_get_seals(int fd)
- {
- long r;
- r = fcntl(fd, F_GET_SEALS);
- if (r < 0) {
- printf("GET_SEALS(%d) failed: %m\n", fd);
- abort();
- }
- return r;
- }
- static void mfd_assert_has_seals(int fd, __u64 seals)
- {
- __u64 s;
- s = mfd_assert_get_seals(fd);
- if (s != seals) {
- printf("%llu != %llu = GET_SEALS(%d)\n",
- (unsigned long long)seals, (unsigned long long)s, fd);
- abort();
- }
- }
- static void mfd_assert_add_seals(int fd, __u64 seals)
- {
- long r;
- __u64 s;
- s = mfd_assert_get_seals(fd);
- r = fcntl(fd, F_ADD_SEALS, seals);
- if (r < 0) {
- printf("ADD_SEALS(%d, %llu -> %llu) failed: %m\n",
- fd, (unsigned long long)s, (unsigned long long)seals);
- abort();
- }
- }
- static void mfd_fail_add_seals(int fd, __u64 seals)
- {
- long r;
- __u64 s;
- r = fcntl(fd, F_GET_SEALS);
- if (r < 0)
- s = 0;
- else
- s = r;
- r = fcntl(fd, F_ADD_SEALS, seals);
- if (r >= 0) {
- printf("ADD_SEALS(%d, %llu -> %llu) didn't fail as expected\n",
- fd, (unsigned long long)s, (unsigned long long)seals);
- abort();
- }
- }
- static void mfd_assert_size(int fd, size_t size)
- {
- struct stat st;
- int r;
- r = fstat(fd, &st);
- if (r < 0) {
- printf("fstat(%d) failed: %m\n", fd);
- abort();
- } else if (st.st_size != size) {
- printf("wrong file size %lld, but expected %lld\n",
- (long long)st.st_size, (long long)size);
- abort();
- }
- }
- static int mfd_assert_dup(int fd)
- {
- int r;
- r = dup(fd);
- if (r < 0) {
- printf("dup(%d) failed: %m\n", fd);
- abort();
- }
- return r;
- }
- static void *mfd_assert_mmap_shared(int fd)
- {
- void *p;
- p = mmap(NULL,
- MFD_DEF_SIZE,
- PROT_READ | PROT_WRITE,
- MAP_SHARED,
- fd,
- 0);
- if (p == MAP_FAILED) {
- printf("mmap() failed: %m\n");
- abort();
- }
- return p;
- }
- static void *mfd_assert_mmap_private(int fd)
- {
- void *p;
- p = mmap(NULL,
- MFD_DEF_SIZE,
- PROT_READ,
- MAP_PRIVATE,
- fd,
- 0);
- if (p == MAP_FAILED) {
- printf("mmap() failed: %m\n");
- abort();
- }
- return p;
- }
- static int mfd_assert_open(int fd, int flags, mode_t mode)
- {
- char buf[512];
- int r;
- sprintf(buf, "/proc/self/fd/%d", fd);
- r = open(buf, flags, mode);
- if (r < 0) {
- printf("open(%s) failed: %m\n", buf);
- abort();
- }
- return r;
- }
- static void mfd_fail_open(int fd, int flags, mode_t mode)
- {
- char buf[512];
- int r;
- sprintf(buf, "/proc/self/fd/%d", fd);
- r = open(buf, flags, mode);
- if (r >= 0) {
- printf("open(%s) didn't fail as expected\n");
- abort();
- }
- }
- static void mfd_assert_read(int fd)
- {
- char buf[16];
- void *p;
- ssize_t l;
- l = read(fd, buf, sizeof(buf));
- if (l != sizeof(buf)) {
- printf("read() failed: %m\n");
- abort();
- }
- /* verify PROT_READ *is* allowed */
- p = mmap(NULL,
- MFD_DEF_SIZE,
- PROT_READ,
- MAP_PRIVATE,
- fd,
- 0);
- if (p == MAP_FAILED) {
- printf("mmap() failed: %m\n");
- abort();
- }
- munmap(p, MFD_DEF_SIZE);
- /* verify MAP_PRIVATE is *always* allowed (even writable) */
- p = mmap(NULL,
- MFD_DEF_SIZE,
- PROT_READ | PROT_WRITE,
- MAP_PRIVATE,
- fd,
- 0);
- if (p == MAP_FAILED) {
- printf("mmap() failed: %m\n");
- abort();
- }
- munmap(p, MFD_DEF_SIZE);
- }
- static void mfd_assert_write(int fd)
- {
- ssize_t l;
- void *p;
- int r;
- /* verify write() succeeds */
- l = write(fd, "\0\0\0\0", 4);
- if (l != 4) {
- printf("write() failed: %m\n");
- abort();
- }
- /* verify PROT_READ | PROT_WRITE is allowed */
- p = mmap(NULL,
- MFD_DEF_SIZE,
- PROT_READ | PROT_WRITE,
- MAP_SHARED,
- fd,
- 0);
- if (p == MAP_FAILED) {
- printf("mmap() failed: %m\n");
- abort();
- }
- *(char *)p = 0;
- munmap(p, MFD_DEF_SIZE);
- /* verify PROT_WRITE is allowed */
- p = mmap(NULL,
- MFD_DEF_SIZE,
- PROT_WRITE,
- MAP_SHARED,
- fd,
- 0);
- if (p == MAP_FAILED) {
- printf("mmap() failed: %m\n");
- abort();
- }
- *(char *)p = 0;
- munmap(p, MFD_DEF_SIZE);
- /* verify PROT_READ with MAP_SHARED is allowed and a following
- * mprotect(PROT_WRITE) allows writing */
- p = mmap(NULL,
- MFD_DEF_SIZE,
- PROT_READ,
- MAP_SHARED,
- fd,
- 0);
- if (p == MAP_FAILED) {
- printf("mmap() failed: %m\n");
- abort();
- }
- r = mprotect(p, MFD_DEF_SIZE, PROT_READ | PROT_WRITE);
- if (r < 0) {
- printf("mprotect() failed: %m\n");
- abort();
- }
- *(char *)p = 0;
- munmap(p, MFD_DEF_SIZE);
- /* verify PUNCH_HOLE works */
- r = fallocate(fd,
- FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
- 0,
- MFD_DEF_SIZE);
- if (r < 0) {
- printf("fallocate(PUNCH_HOLE) failed: %m\n");
- abort();
- }
- }
- static void mfd_fail_write(int fd)
- {
- ssize_t l;
- void *p;
- int r;
- /* verify write() fails */
- l = write(fd, "data", 4);
- if (l != -EPERM) {
- printf("expected EPERM on write(), but got %d: %m\n", (int)l);
- abort();
- }
- /* verify PROT_READ | PROT_WRITE is not allowed */
- p = mmap(NULL,
- MFD_DEF_SIZE,
- PROT_READ | PROT_WRITE,
- MAP_SHARED,
- fd,
- 0);
- if (p != MAP_FAILED) {
- printf("mmap() didn't fail as expected\n");
- abort();
- }
- /* verify PROT_WRITE is not allowed */
- p = mmap(NULL,
- MFD_DEF_SIZE,
- PROT_WRITE,
- MAP_SHARED,
- fd,
- 0);
- if (p != MAP_FAILED) {
- printf("mmap() didn't fail as expected\n");
- abort();
- }
- /* Verify PROT_READ with MAP_SHARED with a following mprotect is not
- * allowed. Note that for r/w the kernel already prevents the mmap. */
- p = mmap(NULL,
- MFD_DEF_SIZE,
- PROT_READ,
- MAP_SHARED,
- fd,
- 0);
- if (p != MAP_FAILED) {
- r = mprotect(p, MFD_DEF_SIZE, PROT_READ | PROT_WRITE);
- if (r >= 0) {
- printf("mmap()+mprotect() didn't fail as expected\n");
- abort();
- }
- }
- /* verify PUNCH_HOLE fails */
- r = fallocate(fd,
- FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
- 0,
- MFD_DEF_SIZE);
- if (r >= 0) {
- printf("fallocate(PUNCH_HOLE) didn't fail as expected\n");
- abort();
- }
- }
- static void mfd_assert_shrink(int fd)
- {
- int r, fd2;
- r = ftruncate(fd, MFD_DEF_SIZE / 2);
- if (r < 0) {
- printf("ftruncate(SHRINK) failed: %m\n");
- abort();
- }
- mfd_assert_size(fd, MFD_DEF_SIZE / 2);
- fd2 = mfd_assert_open(fd,
- O_RDWR | O_CREAT | O_TRUNC,
- S_IRUSR | S_IWUSR);
- close(fd2);
- mfd_assert_size(fd, 0);
- }
- static void mfd_fail_shrink(int fd)
- {
- int r;
- r = ftruncate(fd, MFD_DEF_SIZE / 2);
- if (r >= 0) {
- printf("ftruncate(SHRINK) didn't fail as expected\n");
- abort();
- }
- mfd_fail_open(fd,
- O_RDWR | O_CREAT | O_TRUNC,
- S_IRUSR | S_IWUSR);
- }
- static void mfd_assert_grow(int fd)
- {
- int r;
- r = ftruncate(fd, MFD_DEF_SIZE * 2);
- if (r < 0) {
- printf("ftruncate(GROW) failed: %m\n");
- abort();
- }
- mfd_assert_size(fd, MFD_DEF_SIZE * 2);
- r = fallocate(fd,
- 0,
- 0,
- MFD_DEF_SIZE * 4);
- if (r < 0) {
- printf("fallocate(ALLOC) failed: %m\n");
- abort();
- }
- mfd_assert_size(fd, MFD_DEF_SIZE * 4);
- }
- static void mfd_fail_grow(int fd)
- {
- int r;
- r = ftruncate(fd, MFD_DEF_SIZE * 2);
- if (r >= 0) {
- printf("ftruncate(GROW) didn't fail as expected\n");
- abort();
- }
- r = fallocate(fd,
- 0,
- 0,
- MFD_DEF_SIZE * 4);
- if (r >= 0) {
- printf("fallocate(ALLOC) didn't fail as expected\n");
- abort();
- }
- }
- static void mfd_assert_grow_write(int fd)
- {
- static char buf[MFD_DEF_SIZE * 8];
- ssize_t l;
- l = pwrite(fd, buf, sizeof(buf), 0);
- if (l != sizeof(buf)) {
- printf("pwrite() failed: %m\n");
- abort();
- }
- mfd_assert_size(fd, MFD_DEF_SIZE * 8);
- }
- static void mfd_fail_grow_write(int fd)
- {
- static char buf[MFD_DEF_SIZE * 8];
- ssize_t l;
- l = pwrite(fd, buf, sizeof(buf), 0);
- if (l == sizeof(buf)) {
- printf("pwrite() didn't fail as expected\n");
- abort();
- }
- }
- static int idle_thread_fn(void *arg)
- {
- sigset_t set;
- int sig;
- /* dummy waiter; SIGTERM terminates us anyway */
- sigemptyset(&set);
- sigaddset(&set, SIGTERM);
- sigwait(&set, &sig);
- return 0;
- }
- static pid_t spawn_idle_thread(unsigned int flags)
- {
- uint8_t *stack;
- pid_t pid;
- stack = malloc(STACK_SIZE);
- if (!stack) {
- printf("malloc(STACK_SIZE) failed: %m\n");
- abort();
- }
- pid = clone(idle_thread_fn,
- stack + STACK_SIZE,
- SIGCHLD | flags,
- NULL);
- if (pid < 0) {
- printf("clone() failed: %m\n");
- abort();
- }
- return pid;
- }
- static void join_idle_thread(pid_t pid)
- {
- kill(pid, SIGTERM);
- waitpid(pid, NULL, 0);
- }
- /*
- * Test memfd_create() syscall
- * Verify syscall-argument validation, including name checks, flag validation
- * and more.
- */
- static void test_create(void)
- {
- char buf[2048];
- int fd;
- /* test NULL name */
- mfd_fail_new(NULL, 0);
- /* test over-long name (not zero-terminated) */
- memset(buf, 0xff, sizeof(buf));
- mfd_fail_new(buf, 0);
- /* test over-long zero-terminated name */
- memset(buf, 0xff, sizeof(buf));
- buf[sizeof(buf) - 1] = 0;
- mfd_fail_new(buf, 0);
- /* verify "" is a valid name */
- fd = mfd_assert_new("", 0, 0);
- close(fd);
- /* verify invalid O_* open flags */
- mfd_fail_new("", 0x0100);
- mfd_fail_new("", ~MFD_CLOEXEC);
- mfd_fail_new("", ~MFD_ALLOW_SEALING);
- mfd_fail_new("", ~0);
- mfd_fail_new("", 0x80000000U);
- /* verify MFD_CLOEXEC is allowed */
- fd = mfd_assert_new("", 0, MFD_CLOEXEC);
- close(fd);
- /* verify MFD_ALLOW_SEALING is allowed */
- fd = mfd_assert_new("", 0, MFD_ALLOW_SEALING);
- close(fd);
- /* verify MFD_ALLOW_SEALING | MFD_CLOEXEC is allowed */
- fd = mfd_assert_new("", 0, MFD_ALLOW_SEALING | MFD_CLOEXEC);
- close(fd);
- }
- /*
- * Test basic sealing
- * A very basic sealing test to see whether setting/retrieving seals works.
- */
- static void test_basic(void)
- {
- int fd;
- fd = mfd_assert_new("kern_memfd_basic",
- MFD_DEF_SIZE,
- MFD_CLOEXEC | MFD_ALLOW_SEALING);
- /* add basic seals */
- mfd_assert_has_seals(fd, 0);
- mfd_assert_add_seals(fd, F_SEAL_SHRINK |
- F_SEAL_WRITE);
- mfd_assert_has_seals(fd, F_SEAL_SHRINK |
- F_SEAL_WRITE);
- /* add them again */
- mfd_assert_add_seals(fd, F_SEAL_SHRINK |
- F_SEAL_WRITE);
- mfd_assert_has_seals(fd, F_SEAL_SHRINK |
- F_SEAL_WRITE);
- /* add more seals and seal against sealing */
- mfd_assert_add_seals(fd, F_SEAL_GROW | F_SEAL_SEAL);
- mfd_assert_has_seals(fd, F_SEAL_SHRINK |
- F_SEAL_GROW |
- F_SEAL_WRITE |
- F_SEAL_SEAL);
- /* verify that sealing no longer works */
- mfd_fail_add_seals(fd, F_SEAL_GROW);
- mfd_fail_add_seals(fd, 0);
- close(fd);
- /* verify sealing does not work without MFD_ALLOW_SEALING */
- fd = mfd_assert_new("kern_memfd_basic",
- MFD_DEF_SIZE,
- MFD_CLOEXEC);
- mfd_assert_has_seals(fd, F_SEAL_SEAL);
- mfd_fail_add_seals(fd, F_SEAL_SHRINK |
- F_SEAL_GROW |
- F_SEAL_WRITE);
- mfd_assert_has_seals(fd, F_SEAL_SEAL);
- close(fd);
- }
- /*
- * Test SEAL_WRITE
- * Test whether SEAL_WRITE actually prevents modifications.
- */
- static void test_seal_write(void)
- {
- int fd;
- fd = mfd_assert_new("kern_memfd_seal_write",
- MFD_DEF_SIZE,
- MFD_CLOEXEC | MFD_ALLOW_SEALING);
- mfd_assert_has_seals(fd, 0);
- mfd_assert_add_seals(fd, F_SEAL_WRITE);
- mfd_assert_has_seals(fd, F_SEAL_WRITE);
- mfd_assert_read(fd);
- mfd_fail_write(fd);
- mfd_assert_shrink(fd);
- mfd_assert_grow(fd);
- mfd_fail_grow_write(fd);
- close(fd);
- }
- /*
- * Test SEAL_SHRINK
- * Test whether SEAL_SHRINK actually prevents shrinking
- */
- static void test_seal_shrink(void)
- {
- int fd;
- fd = mfd_assert_new("kern_memfd_seal_shrink",
- MFD_DEF_SIZE,
- MFD_CLOEXEC | MFD_ALLOW_SEALING);
- mfd_assert_has_seals(fd, 0);
- mfd_assert_add_seals(fd, F_SEAL_SHRINK);
- mfd_assert_has_seals(fd, F_SEAL_SHRINK);
- mfd_assert_read(fd);
- mfd_assert_write(fd);
- mfd_fail_shrink(fd);
- mfd_assert_grow(fd);
- mfd_assert_grow_write(fd);
- close(fd);
- }
- /*
- * Test SEAL_GROW
- * Test whether SEAL_GROW actually prevents growing
- */
- static void test_seal_grow(void)
- {
- int fd;
- fd = mfd_assert_new("kern_memfd_seal_grow",
- MFD_DEF_SIZE,
- MFD_CLOEXEC | MFD_ALLOW_SEALING);
- mfd_assert_has_seals(fd, 0);
- mfd_assert_add_seals(fd, F_SEAL_GROW);
- mfd_assert_has_seals(fd, F_SEAL_GROW);
- mfd_assert_read(fd);
- mfd_assert_write(fd);
- mfd_assert_shrink(fd);
- mfd_fail_grow(fd);
- mfd_fail_grow_write(fd);
- close(fd);
- }
- /*
- * Test SEAL_SHRINK | SEAL_GROW
- * Test whether SEAL_SHRINK | SEAL_GROW actually prevents resizing
- */
- static void test_seal_resize(void)
- {
- int fd;
- fd = mfd_assert_new("kern_memfd_seal_resize",
- MFD_DEF_SIZE,
- MFD_CLOEXEC | MFD_ALLOW_SEALING);
- mfd_assert_has_seals(fd, 0);
- mfd_assert_add_seals(fd, F_SEAL_SHRINK | F_SEAL_GROW);
- mfd_assert_has_seals(fd, F_SEAL_SHRINK | F_SEAL_GROW);
- mfd_assert_read(fd);
- mfd_assert_write(fd);
- mfd_fail_shrink(fd);
- mfd_fail_grow(fd);
- mfd_fail_grow_write(fd);
- close(fd);
- }
- /*
- * Test sharing via dup()
- * Test that seals are shared between dupped FDs and they're all equal.
- */
- static void test_share_dup(void)
- {
- int fd, fd2;
- fd = mfd_assert_new("kern_memfd_share_dup",
- MFD_DEF_SIZE,
- MFD_CLOEXEC | MFD_ALLOW_SEALING);
- mfd_assert_has_seals(fd, 0);
- fd2 = mfd_assert_dup(fd);
- mfd_assert_has_seals(fd2, 0);
- mfd_assert_add_seals(fd, F_SEAL_WRITE);
- mfd_assert_has_seals(fd, F_SEAL_WRITE);
- mfd_assert_has_seals(fd2, F_SEAL_WRITE);
- mfd_assert_add_seals(fd2, F_SEAL_SHRINK);
- mfd_assert_has_seals(fd, F_SEAL_WRITE | F_SEAL_SHRINK);
- mfd_assert_has_seals(fd2, F_SEAL_WRITE | F_SEAL_SHRINK);
- mfd_assert_add_seals(fd, F_SEAL_SEAL);
- mfd_assert_has_seals(fd, F_SEAL_WRITE | F_SEAL_SHRINK | F_SEAL_SEAL);
- mfd_assert_has_seals(fd2, F_SEAL_WRITE | F_SEAL_SHRINK | F_SEAL_SEAL);
- mfd_fail_add_seals(fd, F_SEAL_GROW);
- mfd_fail_add_seals(fd2, F_SEAL_GROW);
- mfd_fail_add_seals(fd, F_SEAL_SEAL);
- mfd_fail_add_seals(fd2, F_SEAL_SEAL);
- close(fd2);
- mfd_fail_add_seals(fd, F_SEAL_GROW);
- close(fd);
- }
- /*
- * Test sealing with active mmap()s
- * Modifying seals is only allowed if no other mmap() refs exist.
- */
- static void test_share_mmap(void)
- {
- int fd;
- void *p;
- fd = mfd_assert_new("kern_memfd_share_mmap",
- MFD_DEF_SIZE,
- MFD_CLOEXEC | MFD_ALLOW_SEALING);
- mfd_assert_has_seals(fd, 0);
- /* shared/writable ref prevents sealing WRITE, but allows others */
- p = mfd_assert_mmap_shared(fd);
- mfd_fail_add_seals(fd, F_SEAL_WRITE);
- mfd_assert_has_seals(fd, 0);
- mfd_assert_add_seals(fd, F_SEAL_SHRINK);
- mfd_assert_has_seals(fd, F_SEAL_SHRINK);
- munmap(p, MFD_DEF_SIZE);
- /* readable ref allows sealing */
- p = mfd_assert_mmap_private(fd);
- mfd_assert_add_seals(fd, F_SEAL_WRITE);
- mfd_assert_has_seals(fd, F_SEAL_WRITE | F_SEAL_SHRINK);
- munmap(p, MFD_DEF_SIZE);
- close(fd);
- }
- /*
- * Test sealing with open(/proc/self/fd/%d)
- * Via /proc we can get access to a separate file-context for the same memfd.
- * This is *not* like dup(), but like a real separate open(). Make sure the
- * semantics are as expected and we correctly check for RDONLY / WRONLY / RDWR.
- */
- static void test_share_open(void)
- {
- int fd, fd2;
- fd = mfd_assert_new("kern_memfd_share_open",
- MFD_DEF_SIZE,
- MFD_CLOEXEC | MFD_ALLOW_SEALING);
- mfd_assert_has_seals(fd, 0);
- fd2 = mfd_assert_open(fd, O_RDWR, 0);
- mfd_assert_add_seals(fd, F_SEAL_WRITE);
- mfd_assert_has_seals(fd, F_SEAL_WRITE);
- mfd_assert_has_seals(fd2, F_SEAL_WRITE);
- mfd_assert_add_seals(fd2, F_SEAL_SHRINK);
- mfd_assert_has_seals(fd, F_SEAL_WRITE | F_SEAL_SHRINK);
- mfd_assert_has_seals(fd2, F_SEAL_WRITE | F_SEAL_SHRINK);
- close(fd);
- fd = mfd_assert_open(fd2, O_RDONLY, 0);
- mfd_fail_add_seals(fd, F_SEAL_SEAL);
- mfd_assert_has_seals(fd, F_SEAL_WRITE | F_SEAL_SHRINK);
- mfd_assert_has_seals(fd2, F_SEAL_WRITE | F_SEAL_SHRINK);
- close(fd2);
- fd2 = mfd_assert_open(fd, O_RDWR, 0);
- mfd_assert_add_seals(fd2, F_SEAL_SEAL);
- mfd_assert_has_seals(fd, F_SEAL_WRITE | F_SEAL_SHRINK | F_SEAL_SEAL);
- mfd_assert_has_seals(fd2, F_SEAL_WRITE | F_SEAL_SHRINK | F_SEAL_SEAL);
- close(fd2);
- close(fd);
- }
- /*
- * Test sharing via fork()
- * Test whether seal-modifications work as expected with forked childs.
- */
- static void test_share_fork(void)
- {
- int fd;
- pid_t pid;
- fd = mfd_assert_new("kern_memfd_share_fork",
- MFD_DEF_SIZE,
- MFD_CLOEXEC | MFD_ALLOW_SEALING);
- mfd_assert_has_seals(fd, 0);
- pid = spawn_idle_thread(0);
- mfd_assert_add_seals(fd, F_SEAL_SEAL);
- mfd_assert_has_seals(fd, F_SEAL_SEAL);
- mfd_fail_add_seals(fd, F_SEAL_WRITE);
- mfd_assert_has_seals(fd, F_SEAL_SEAL);
- join_idle_thread(pid);
- mfd_fail_add_seals(fd, F_SEAL_WRITE);
- mfd_assert_has_seals(fd, F_SEAL_SEAL);
- close(fd);
- }
- int main(int argc, char **argv)
- {
- pid_t pid;
- printf("memfd: CREATE\n");
- test_create();
- printf("memfd: BASIC\n");
- test_basic();
- printf("memfd: SEAL-WRITE\n");
- test_seal_write();
- printf("memfd: SEAL-SHRINK\n");
- test_seal_shrink();
- printf("memfd: SEAL-GROW\n");
- test_seal_grow();
- printf("memfd: SEAL-RESIZE\n");
- test_seal_resize();
- printf("memfd: SHARE-DUP\n");
- test_share_dup();
- printf("memfd: SHARE-MMAP\n");
- test_share_mmap();
- printf("memfd: SHARE-OPEN\n");
- test_share_open();
- printf("memfd: SHARE-FORK\n");
- test_share_fork();
- /* Run test-suite in a multi-threaded environment with a shared
- * file-table. */
- pid = spawn_idle_thread(CLONE_FILES | CLONE_FS | CLONE_VM);
- printf("memfd: SHARE-DUP (shared file-table)\n");
- test_share_dup();
- printf("memfd: SHARE-MMAP (shared file-table)\n");
- test_share_mmap();
- printf("memfd: SHARE-OPEN (shared file-table)\n");
- test_share_open();
- printf("memfd: SHARE-FORK (shared file-table)\n");
- test_share_fork();
- join_idle_thread(pid);
- printf("memfd: DONE\n");
- return 0;
- }
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