912 lines
18 KiB
C
912 lines
18 KiB
C
#define _GNU_SOURCE
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#define __EXPORTED_HEADERS__
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#include <errno.h>
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#include <inttypes.h>
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#include <limits.h>
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#include <linux/falloc.h>
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#include <linux/fcntl.h>
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#include <linux/memfd.h>
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#include <sched.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <signal.h>
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#include <string.h>
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#include <sys/mman.h>
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#include <sys/stat.h>
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#include <sys/syscall.h>
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#include <unistd.h>
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#define MFD_DEF_SIZE 8192
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#define STACK_SIZE 65535
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static int sys_memfd_create(const char *name,
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unsigned int flags)
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{
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return syscall(__NR_memfd_create, name, flags);
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}
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static int mfd_assert_new(const char *name, loff_t sz, unsigned int flags)
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{
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int r, fd;
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fd = sys_memfd_create(name, flags);
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if (fd < 0) {
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printf("memfd_create(\"%s\", %u) failed: %m\n",
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name, flags);
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abort();
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}
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r = ftruncate(fd, sz);
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if (r < 0) {
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printf("ftruncate(%llu) failed: %m\n", (unsigned long long)sz);
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abort();
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}
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return fd;
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}
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static void mfd_fail_new(const char *name, unsigned int flags)
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{
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int r;
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r = sys_memfd_create(name, flags);
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if (r >= 0) {
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printf("memfd_create(\"%s\", %u) succeeded, but failure expected\n",
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name, flags);
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close(r);
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abort();
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}
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}
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static unsigned int mfd_assert_get_seals(int fd)
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{
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int r;
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r = fcntl(fd, F_GET_SEALS);
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if (r < 0) {
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printf("GET_SEALS(%d) failed: %m\n", fd);
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abort();
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}
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return (unsigned int)r;
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}
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static void mfd_assert_has_seals(int fd, unsigned int seals)
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{
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unsigned int s;
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s = mfd_assert_get_seals(fd);
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if (s != seals) {
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printf("%u != %u = GET_SEALS(%d)\n", seals, s, fd);
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abort();
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}
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}
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static void mfd_assert_add_seals(int fd, unsigned int seals)
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{
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int r;
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unsigned int s;
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s = mfd_assert_get_seals(fd);
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r = fcntl(fd, F_ADD_SEALS, seals);
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if (r < 0) {
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printf("ADD_SEALS(%d, %u -> %u) failed: %m\n", fd, s, seals);
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abort();
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}
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}
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static void mfd_fail_add_seals(int fd, unsigned int seals)
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{
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int r;
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unsigned int s;
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r = fcntl(fd, F_GET_SEALS);
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if (r < 0)
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s = 0;
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else
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s = (unsigned int)r;
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r = fcntl(fd, F_ADD_SEALS, seals);
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if (r >= 0) {
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printf("ADD_SEALS(%d, %u -> %u) didn't fail as expected\n",
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fd, s, seals);
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abort();
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}
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}
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static void mfd_assert_size(int fd, size_t size)
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{
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struct stat st;
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int r;
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r = fstat(fd, &st);
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if (r < 0) {
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printf("fstat(%d) failed: %m\n", fd);
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abort();
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} else if (st.st_size != size) {
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printf("wrong file size %lld, but expected %lld\n",
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(long long)st.st_size, (long long)size);
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abort();
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}
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}
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static int mfd_assert_dup(int fd)
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{
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int r;
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r = dup(fd);
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if (r < 0) {
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printf("dup(%d) failed: %m\n", fd);
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abort();
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}
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return r;
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}
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static void *mfd_assert_mmap_shared(int fd)
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{
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void *p;
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p = mmap(NULL,
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MFD_DEF_SIZE,
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PROT_READ | PROT_WRITE,
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MAP_SHARED,
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fd,
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0);
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if (p == MAP_FAILED) {
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printf("mmap() failed: %m\n");
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abort();
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}
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return p;
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}
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static void *mfd_assert_mmap_private(int fd)
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{
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void *p;
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p = mmap(NULL,
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MFD_DEF_SIZE,
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PROT_READ,
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MAP_PRIVATE,
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fd,
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0);
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if (p == MAP_FAILED) {
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printf("mmap() failed: %m\n");
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abort();
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}
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return p;
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}
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static int mfd_assert_open(int fd, int flags, mode_t mode)
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{
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char buf[512];
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int r;
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sprintf(buf, "/proc/self/fd/%d", fd);
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r = open(buf, flags, mode);
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if (r < 0) {
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printf("open(%s) failed: %m\n", buf);
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abort();
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}
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return r;
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}
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static void mfd_fail_open(int fd, int flags, mode_t mode)
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{
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char buf[512];
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int r;
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sprintf(buf, "/proc/self/fd/%d", fd);
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r = open(buf, flags, mode);
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if (r >= 0) {
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printf("open(%s) didn't fail as expected\n", buf);
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abort();
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}
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}
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static void mfd_assert_read(int fd)
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{
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char buf[16];
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void *p;
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ssize_t l;
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l = read(fd, buf, sizeof(buf));
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if (l != sizeof(buf)) {
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printf("read() failed: %m\n");
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abort();
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}
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/* verify PROT_READ *is* allowed */
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p = mmap(NULL,
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MFD_DEF_SIZE,
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PROT_READ,
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MAP_PRIVATE,
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fd,
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0);
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if (p == MAP_FAILED) {
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printf("mmap() failed: %m\n");
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abort();
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}
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munmap(p, MFD_DEF_SIZE);
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/* verify MAP_PRIVATE is *always* allowed (even writable) */
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p = mmap(NULL,
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MFD_DEF_SIZE,
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PROT_READ | PROT_WRITE,
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MAP_PRIVATE,
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fd,
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0);
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if (p == MAP_FAILED) {
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printf("mmap() failed: %m\n");
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abort();
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}
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munmap(p, MFD_DEF_SIZE);
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}
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static void mfd_assert_write(int fd)
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{
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ssize_t l;
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void *p;
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int r;
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/* verify write() succeeds */
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l = write(fd, "\0\0\0\0", 4);
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if (l != 4) {
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printf("write() failed: %m\n");
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abort();
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}
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/* verify PROT_READ | PROT_WRITE is allowed */
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p = mmap(NULL,
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MFD_DEF_SIZE,
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PROT_READ | PROT_WRITE,
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MAP_SHARED,
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fd,
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0);
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if (p == MAP_FAILED) {
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printf("mmap() failed: %m\n");
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abort();
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}
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*(char *)p = 0;
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munmap(p, MFD_DEF_SIZE);
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/* verify PROT_WRITE is allowed */
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p = mmap(NULL,
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MFD_DEF_SIZE,
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PROT_WRITE,
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MAP_SHARED,
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fd,
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0);
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if (p == MAP_FAILED) {
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printf("mmap() failed: %m\n");
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abort();
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}
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*(char *)p = 0;
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munmap(p, MFD_DEF_SIZE);
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/* verify PROT_READ with MAP_SHARED is allowed and a following
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* mprotect(PROT_WRITE) allows writing */
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p = mmap(NULL,
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MFD_DEF_SIZE,
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PROT_READ,
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MAP_SHARED,
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fd,
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0);
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if (p == MAP_FAILED) {
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printf("mmap() failed: %m\n");
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abort();
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}
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r = mprotect(p, MFD_DEF_SIZE, PROT_READ | PROT_WRITE);
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if (r < 0) {
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printf("mprotect() failed: %m\n");
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abort();
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}
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*(char *)p = 0;
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munmap(p, MFD_DEF_SIZE);
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/* verify PUNCH_HOLE works */
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r = fallocate(fd,
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FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
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0,
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MFD_DEF_SIZE);
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if (r < 0) {
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printf("fallocate(PUNCH_HOLE) failed: %m\n");
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abort();
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}
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}
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static void mfd_fail_write(int fd)
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{
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ssize_t l;
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void *p;
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int r;
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/* verify write() fails */
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l = write(fd, "data", 4);
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if (l != -EPERM) {
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printf("expected EPERM on write(), but got %d: %m\n", (int)l);
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abort();
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}
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/* verify PROT_READ | PROT_WRITE is not allowed */
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p = mmap(NULL,
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MFD_DEF_SIZE,
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PROT_READ | PROT_WRITE,
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MAP_SHARED,
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fd,
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0);
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if (p != MAP_FAILED) {
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printf("mmap() didn't fail as expected\n");
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abort();
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}
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/* verify PROT_WRITE is not allowed */
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p = mmap(NULL,
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MFD_DEF_SIZE,
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PROT_WRITE,
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MAP_SHARED,
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fd,
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0);
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if (p != MAP_FAILED) {
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printf("mmap() didn't fail as expected\n");
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abort();
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}
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/* Verify PROT_READ with MAP_SHARED with a following mprotect is not
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* allowed. Note that for r/w the kernel already prevents the mmap. */
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p = mmap(NULL,
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MFD_DEF_SIZE,
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PROT_READ,
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MAP_SHARED,
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fd,
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0);
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if (p != MAP_FAILED) {
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r = mprotect(p, MFD_DEF_SIZE, PROT_READ | PROT_WRITE);
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if (r >= 0) {
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printf("mmap()+mprotect() didn't fail as expected\n");
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abort();
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}
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}
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/* verify PUNCH_HOLE fails */
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r = fallocate(fd,
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FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
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0,
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MFD_DEF_SIZE);
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if (r >= 0) {
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printf("fallocate(PUNCH_HOLE) didn't fail as expected\n");
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abort();
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}
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}
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static void mfd_assert_shrink(int fd)
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{
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int r, fd2;
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r = ftruncate(fd, MFD_DEF_SIZE / 2);
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if (r < 0) {
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printf("ftruncate(SHRINK) failed: %m\n");
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abort();
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}
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mfd_assert_size(fd, MFD_DEF_SIZE / 2);
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fd2 = mfd_assert_open(fd,
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O_RDWR | O_CREAT | O_TRUNC,
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S_IRUSR | S_IWUSR);
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close(fd2);
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mfd_assert_size(fd, 0);
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}
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static void mfd_fail_shrink(int fd)
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{
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int r;
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r = ftruncate(fd, MFD_DEF_SIZE / 2);
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if (r >= 0) {
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printf("ftruncate(SHRINK) didn't fail as expected\n");
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abort();
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}
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mfd_fail_open(fd,
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O_RDWR | O_CREAT | O_TRUNC,
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S_IRUSR | S_IWUSR);
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}
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static void mfd_assert_grow(int fd)
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{
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int r;
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r = ftruncate(fd, MFD_DEF_SIZE * 2);
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if (r < 0) {
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printf("ftruncate(GROW) failed: %m\n");
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abort();
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}
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mfd_assert_size(fd, MFD_DEF_SIZE * 2);
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r = fallocate(fd,
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0,
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0,
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MFD_DEF_SIZE * 4);
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if (r < 0) {
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printf("fallocate(ALLOC) failed: %m\n");
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abort();
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}
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mfd_assert_size(fd, MFD_DEF_SIZE * 4);
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}
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static void mfd_fail_grow(int fd)
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{
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int r;
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r = ftruncate(fd, MFD_DEF_SIZE * 2);
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if (r >= 0) {
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printf("ftruncate(GROW) didn't fail as expected\n");
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abort();
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}
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r = fallocate(fd,
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0,
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0,
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MFD_DEF_SIZE * 4);
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if (r >= 0) {
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printf("fallocate(ALLOC) didn't fail as expected\n");
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abort();
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}
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}
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static void mfd_assert_grow_write(int fd)
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{
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static char buf[MFD_DEF_SIZE * 8];
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ssize_t l;
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l = pwrite(fd, buf, sizeof(buf), 0);
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if (l != sizeof(buf)) {
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printf("pwrite() failed: %m\n");
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abort();
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}
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mfd_assert_size(fd, MFD_DEF_SIZE * 8);
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}
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static void mfd_fail_grow_write(int fd)
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{
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static char buf[MFD_DEF_SIZE * 8];
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ssize_t l;
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l = pwrite(fd, buf, sizeof(buf), 0);
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if (l == sizeof(buf)) {
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printf("pwrite() didn't fail as expected\n");
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abort();
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}
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}
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static int idle_thread_fn(void *arg)
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{
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sigset_t set;
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int sig;
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/* dummy waiter; SIGTERM terminates us anyway */
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sigemptyset(&set);
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sigaddset(&set, SIGTERM);
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sigwait(&set, &sig);
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return 0;
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}
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static pid_t spawn_idle_thread(unsigned int flags)
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{
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uint8_t *stack;
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pid_t pid;
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stack = malloc(STACK_SIZE);
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if (!stack) {
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printf("malloc(STACK_SIZE) failed: %m\n");
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abort();
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}
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pid = clone(idle_thread_fn,
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stack + STACK_SIZE,
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SIGCHLD | flags,
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NULL);
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if (pid < 0) {
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printf("clone() failed: %m\n");
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abort();
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}
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return pid;
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}
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static void join_idle_thread(pid_t pid)
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{
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kill(pid, SIGTERM);
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waitpid(pid, NULL, 0);
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}
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/*
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* Test memfd_create() syscall
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* Verify syscall-argument validation, including name checks, flag validation
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* and more.
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*/
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static void test_create(void)
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{
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char buf[2048];
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int fd;
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/* test NULL name */
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mfd_fail_new(NULL, 0);
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/* test over-long name (not zero-terminated) */
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memset(buf, 0xff, sizeof(buf));
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mfd_fail_new(buf, 0);
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/* test over-long zero-terminated name */
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memset(buf, 0xff, sizeof(buf));
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buf[sizeof(buf) - 1] = 0;
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mfd_fail_new(buf, 0);
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/* verify "" is a valid name */
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fd = mfd_assert_new("", 0, 0);
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close(fd);
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/* verify invalid O_* open flags */
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mfd_fail_new("", 0x0100);
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mfd_fail_new("", ~MFD_CLOEXEC);
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mfd_fail_new("", ~MFD_ALLOW_SEALING);
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mfd_fail_new("", ~0);
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mfd_fail_new("", 0x80000000U);
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/* verify MFD_CLOEXEC is allowed */
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fd = mfd_assert_new("", 0, MFD_CLOEXEC);
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close(fd);
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/* verify MFD_ALLOW_SEALING is allowed */
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fd = mfd_assert_new("", 0, MFD_ALLOW_SEALING);
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close(fd);
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/* verify MFD_ALLOW_SEALING | MFD_CLOEXEC is allowed */
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fd = mfd_assert_new("", 0, MFD_ALLOW_SEALING | MFD_CLOEXEC);
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close(fd);
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}
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/*
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* Test basic sealing
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* A very basic sealing test to see whether setting/retrieving seals works.
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*/
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static void test_basic(void)
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|
{
|
|
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;
|
|
}
|