1  /*
       2   * Check decoding of memfd_secret syscall.
       3   *
       4   * Copyright (c) 2021 Eugene Syromyatnikov <evgsyr@gmail.com>
       5   * All rights reserved.
       6   *
       7   * SPDX-License-Identifier: GPL-2.0-or-later
       8   */
       9  
      10  #include "tests.h"
      11  #include "kernel_fcntl.h"
      12  #include "scno.h"
      13  
      14  #include <inttypes.h>
      15  #include <errno.h>
      16  #include <stdio.h>
      17  #include <stdint.h>
      18  #include <unistd.h>
      19  
      20  #ifndef RETVAL_INJECTED
      21  # define RETVAL_INJECTED 0
      22  #endif
      23  
      24  #ifndef SKIP_IF_PROC_IS_UNAVAILABLE
      25  # define SKIP_IF_PROC_IS_UNAVAILABLE
      26  #endif
      27  #ifndef FD_PATH
      28  # define FD_PATH ""
      29  #endif
      30  
      31  #if RETVAL_INJECTED
      32  # define INJ_STR " (INJECTED)\n"
      33  # define INJ_FD_STR FD_PATH " (INJECTED)\n"
      34  #else /* !RETVAL_INJECTED */
      35  # define INJ_STR "\n"
      36  # define INJ_FD_STR "\n"
      37  #endif /* RETVAL_INJECTED */
      38  
      39  static const char *errstr;
      40  
      41  
      42  static long
      43  sys_memfd_secret(unsigned int flags)
      44  
      45  {
      46  	static const kernel_ulong_t fill =
      47  		(kernel_ulong_t) 0xbeefcafe00000000ULL;
      48  	kernel_ulong_t arg1 = fill | flags;
      49  	kernel_ulong_t arg2 = fill | 0xdefaeced;
      50  	kernel_ulong_t arg3 = fill | 0xbabefeed;
      51  	kernel_ulong_t arg4 = fill | 0xbadbeefd;
      52  	kernel_ulong_t arg5 = fill | 0xdecaffed;
      53  	kernel_ulong_t arg6 = fill | 0xdeefaced;
      54  
      55  	long rc = syscall(__NR_memfd_secret,
      56  			  arg1, arg2, arg3, arg4, arg5, arg6);
      57  	errstr = sprintrc(rc);
      58  
      59  	return rc;
      60  }
      61  
      62  int
      63  main(void)
      64  {
      65  	SKIP_IF_PROC_IS_UNAVAILABLE;
      66  
      67  	static const struct {
      68  		int val;
      69  		const char *str;
      70  	} flags_vals[] = {
      71  		{ ARG_STR(0) },
      72  		{ ARG_STR(O_CLOEXEC) },
      73  		/* O_CLOEXEC is either 0x80000, 0x200000, or 0x400000 */
      74  		{ ARG_STR(0xde97face) },
      75  		{ ARG_STR(O_CLOEXEC|0xde97face) },
      76  	};
      77  	for (size_t i = 0; i < ARRAY_SIZE(flags_vals); i++) {
      78  		long rc = sys_memfd_secret(flags_vals[i].val);
      79  		printf("memfd_secret(%s) = %s%s" INJ_STR,
      80  		       flags_vals[i].str, errstr, rc > 0 ? FD_PATH : "");
      81  	}
      82  
      83  	puts("+++ exited with 0 +++");
      84  	return 0;
      85  }