1  /*
       2   * Check decoding of setreuid/setregid/setreuid32/setregid32 syscalls.
       3   *
       4   * Copyright (c) 2016-2021 Dmitry V. Levin <ldv@strace.io>
       5   * All rights reserved.
       6   *
       7   * SPDX-License-Identifier: GPL-2.0-or-later
       8   */
       9  
      10  #include <errno.h>
      11  #include <stdio.h>
      12  #include <unistd.h>
      13  
      14  static int
      15  ugid2int(const unsigned UGID_TYPE ugid)
      16  {
      17  	if ((unsigned UGID_TYPE) -1U == ugid)
      18  		return -1;
      19  	else
      20  		return ugid;
      21  }
      22  
      23  static void
      24  print_int(const unsigned int num)
      25  {
      26  	if (num == -1U)
      27  		printf("-1");
      28  	else
      29  		printf("%u", num);
      30  }
      31  
      32  static int
      33  num_matches_id(const unsigned int num, const unsigned int ugid)
      34  {
      35  	return num == ugid || num == -1U;
      36  }
      37  
      38  #define PAIR(val)	{ val, ugid }, { ugid, val }
      39  
      40  int
      41  main(void)
      42  {
      43  	unsigned int ugid = GETUGID;
      44  	CHECK_OVERFLOWUGID(ugid);
      45  
      46  	const struct {
      47  		const long r, e;
      48  	} tests[] = {
      49  		{ ugid, ugid },
      50  		PAIR((unsigned long) 0xffffffff00000000ULL | ugid),
      51  		PAIR(-1U),
      52  		PAIR(-1L),
      53  		PAIR(0xffff0000U | ugid),
      54  		PAIR(0xffff),
      55  		PAIR(0xc0deffffU)
      56  	};
      57  
      58  	for (unsigned int i = 0; i < ARRAY_SIZE(tests); ++i) {
      59  		const unsigned int rn = ugid2int(tests[i].r);
      60  		const unsigned int en = ugid2int(tests[i].e);
      61  
      62  		if (!num_matches_id(rn, ugid) || !num_matches_id(en, ugid))
      63  			continue;
      64  
      65  		if (syscall(SYSCALL_NR, tests[i].r, tests[i].e)) {
      66  			if (!i && ENOSYS == errno) {
      67  				printf("%s(%u, %u) = -1 ENOSYS (%m)\n",
      68  				       SYSCALL_NAME, ugid, ugid);
      69  				break;
      70  			}
      71  			perror_msg_and_fail("%s(%#lx, %#lx)", SYSCALL_NAME,
      72  					    tests[i].r, tests[i].e);
      73  		}
      74  
      75  		printf("%s(", SYSCALL_NAME);
      76  		print_int(rn);
      77  		printf(", ");
      78  		print_int(en);
      79  		printf(") = 0\n");
      80  	}
      81  
      82  	puts("+++ exited with 0 +++");
      83  	return 0;
      84  }