1  /*
       2   * Check decoding of landlock_add_rule syscall.
       3   *
       4   * Copyright (c) 2021 Eugene Syromyatnikov <evgsyr@gmail.com>
       5   * Copyright (c) 2021-2023 The strace developers.
       6   * All rights reserved.
       7   *
       8   * SPDX-License-Identifier: GPL-2.0-or-later
       9   */
      10  
      11  #include "tests.h"
      12  #include "scno.h"
      13  
      14  #include <inttypes.h>
      15  #include <stdio.h>
      16  #include <stdint.h>
      17  #include <unistd.h>
      18  
      19  #include <linux/landlock.h>
      20  
      21  #ifndef SKIP_IF_PROC_IS_UNAVAILABLE
      22  # define SKIP_IF_PROC_IS_UNAVAILABLE
      23  #endif
      24  
      25  #ifndef FD0_STR
      26  # define FD0_STR ""
      27  #endif
      28  #ifndef RULESET_FD
      29  # define RULESET_FD -1
      30  #endif
      31  #ifndef RULESET_FD_STR
      32  # define RULESET_FD_STR "-1"
      33  #endif
      34  #ifndef PARENT_FD
      35  # define PARENT_FD -1
      36  #endif
      37  #ifndef PARENT_FD_STR
      38  # define PARENT_FD_STR "-1"
      39  #endif
      40  
      41  static const char *errstr;
      42  
      43  static long
      44  sys_landlock_add_rule(int ruleset_fd, unsigned int rule_type, void *rule_attr,
      45  		      unsigned int flags)
      46  {
      47  	static const kernel_ulong_t fill =
      48  		(kernel_ulong_t) 0xd1efaced00000000ULL;
      49  	kernel_ulong_t arg1 = fill | (unsigned int) ruleset_fd;
      50  	kernel_ulong_t arg2 = fill | rule_type;
      51  	kernel_ulong_t arg3 = (uintptr_t) rule_attr;
      52  	kernel_ulong_t arg4 = fill | flags;
      53  	kernel_ulong_t arg5 = fill | 0xdecaffed;
      54  	kernel_ulong_t arg6 = fill | 0xdeefaced;
      55  
      56  	long rc = syscall(__NR_landlock_add_rule,
      57  			  arg1, arg2, arg3, arg4, arg5, arg6);
      58  	errstr = sprintrc(rc);
      59  	return rc;
      60  }
      61  
      62  int
      63  main(void)
      64  {
      65  	SKIP_IF_PROC_IS_UNAVAILABLE;
      66  
      67  	TAIL_ALLOC_OBJECT_VAR_PTR(struct landlock_path_beneath_attr, attr);
      68  
      69  	/* All zeroes */
      70  	sys_landlock_add_rule(0, 0, NULL, 0);
      71  	printf("landlock_add_rule(0" FD0_STR ", 0 /* LANDLOCK_RULE_??? */"
      72  	       ", NULL, 0) = %s\n", errstr);
      73  
      74  	/* Bogus values */
      75  	sys_landlock_add_rule(0xdeadc0de, 0xfacebeef, attr + 1, 1);
      76  	printf("landlock_add_rule(-559038242"
      77  	       ", 0xfacebeef /* LANDLOCK_RULE_??? */, %p, 0x1) = %s\n",
      78  	       attr + 1, errstr);
      79  
      80  	sys_landlock_add_rule(1729, 2, attr + 1, 0xffffffff);
      81  	printf("landlock_add_rule(1729, 0x2 /* LANDLOCK_RULE_??? */, %p"
      82  	       ", 0xffffffff) = %s\n",
      83  	       attr + 1, errstr);
      84  
      85  	/* Invalid pointer */
      86  	sys_landlock_add_rule(RULESET_FD, LANDLOCK_RULE_PATH_BENEATH,
      87  			      attr + 1, 0);
      88  	printf("landlock_add_rule(" RULESET_FD_STR
      89  	       ", LANDLOCK_RULE_PATH_BENEATH, %p, 0) = %s\n",
      90  	       attr + 1, errstr);
      91  
      92  	/* Short read */
      93  	sys_landlock_add_rule(RULESET_FD, LANDLOCK_RULE_PATH_BENEATH,
      94  			      (char *) attr + 4, 0);
      95  	printf("landlock_add_rule(" RULESET_FD_STR
      96  	       ", LANDLOCK_RULE_PATH_BENEATH, %p, 0) = %s\n",
      97  	       (char *) attr + 4, errstr);
      98  
      99  	/* Valid attr ptr */
     100  	static const struct {
     101  		uint64_t val;
     102  		const char *str;
     103  	} attr_vals[] = {
     104  		{ ARG_STR(LANDLOCK_ACCESS_FS_EXECUTE) },
     105  		{ ARG_ULL_STR(LANDLOCK_ACCESS_FS_EXECUTE|LANDLOCK_ACCESS_FS_READ_FILE|LANDLOCK_ACCESS_FS_READ_DIR|LANDLOCK_ACCESS_FS_REMOVE_FILE|LANDLOCK_ACCESS_FS_MAKE_CHAR|LANDLOCK_ACCESS_FS_MAKE_DIR|LANDLOCK_ACCESS_FS_MAKE_SOCK|LANDLOCK_ACCESS_FS_MAKE_FIFO|LANDLOCK_ACCESS_FS_MAKE_BLOCK|LANDLOCK_ACCESS_FS_MAKE_SYM|LANDLOCK_ACCESS_FS_REFER|LANDLOCK_ACCESS_FS_TRUNCATE|0xdebeefeddeca8000) },
     106  		{ ARG_ULL_STR(0xdebeefeddeca8000)
     107  			" /* LANDLOCK_ACCESS_FS_??? */" },
     108  	};
     109  	static const struct {
     110  		int val;
     111  		const char *str;
     112  	} parent_fd_vals[] = {
     113  		{ ARG_STR(-1) },
     114  		{ ARG_STR(11630) },
     115  		{ PARENT_FD, PARENT_FD_STR },
     116  	};
     117  	for (size_t i = 0; i < ARRAY_SIZE(attr_vals); i++) {
     118  		for (size_t j = 0; j < ARRAY_SIZE(parent_fd_vals); j++) {
     119  			attr->allowed_access = attr_vals[i].val;
     120  			attr->parent_fd = parent_fd_vals[j].val;
     121  			sys_landlock_add_rule(RULESET_FD,
     122  					      LANDLOCK_RULE_PATH_BENEATH,
     123  					      attr, 0);
     124  			printf("landlock_add_rule(" RULESET_FD_STR
     125  			       ", LANDLOCK_RULE_PATH_BENEATH"
     126  			       ", {allowed_access=%s, parent_fd=%s}, 0) = %s\n",
     127  			       attr_vals[i].str, parent_fd_vals[j].str, errstr);
     128  		}
     129  	}
     130  
     131  	puts("+++ exited with 0 +++");
     132  	return 0;
     133  }