LXR linux/tools/testing/selftests/proc/proc-fsconfig-hidepid.c

   1/*
   2 * Copyright © 2020 Alexey Gladkov <gladkov.alexey@gmail.com>
   3 *
   4 * Permission to use, copy, modify, and distribute this software for any
   5 * purpose with or without fee is hereby granted, provided that the above
   6 * copyright notice and this permission notice appear in all copies.
   7 *
   8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  14 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  15 */
  16#include <assert.h>
  17#include <unistd.h>
  18#include <stdlib.h>
  19#include <errno.h>
  20#include <linux/mount.h>
  21#include <linux/unistd.h>
  22
  23static inline int fsopen(const char *fsname, unsigned int flags)
  24{
  25        return syscall(__NR_fsopen, fsname, flags);
  26}
  27
  28static inline int fsconfig(int fd, unsigned int cmd, const char *key, const void *val, int aux)
  29{
  30        return syscall(__NR_fsconfig, fd, cmd, key, val, aux);
  31}
  32
  33int main(void)
  34{
  35        int fsfd, ret;
  36        int hidepid = 2;
  37
  38        assert((fsfd = fsopen("proc", 0)) != -1);
  39
  40        ret = fsconfig(fsfd, FSCONFIG_SET_BINARY, "hidepid", &hidepid, 0);
  41        assert(ret == -1);
  42        assert(errno == EINVAL);
  43
  44        assert(!fsconfig(fsfd, FSCONFIG_SET_STRING, "hidepid", "2", 0));
  45        assert(!fsconfig(fsfd, FSCONFIG_SET_STRING, "hidepid", "invisible", 0));
  46
  47        assert(!close(fsfd));
  48
  49        return 0;
  50}
  51