• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Check decoding of PR_SET_SPECULATION_CTRL and PR_GET_SPECULATION_CTRL
3  * prctl operations.
4  *
5  * Copyright (c) 2018 The strace developers.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. The name of the author may not be used to endorse or promote products
17  *    derived from this software without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 #include "tests.h"
32 #include <asm/unistd.h>
33 
34 #ifdef __NR_prctl
35 
36 # include <stdio.h>
37 # include <stdlib.h>
38 # include <unistd.h>
39 # include <linux/prctl.h>
40 
41 static long injected_val;
42 
43 long
do_prctl(kernel_ulong_t cmd,kernel_ulong_t arg2,kernel_ulong_t arg3)44 do_prctl(kernel_ulong_t cmd, kernel_ulong_t arg2, kernel_ulong_t arg3)
45 {
46 	long rc = syscall(__NR_prctl, cmd, arg2, arg3);
47 
48 	if (rc != injected_val)
49 		error_msg_and_fail("Return value (%ld) differs from expected "
50 				   "injected value (%ld)",
51 				   rc, injected_val);
52 
53 	return rc;
54 }
55 
56 int
main(int argc,char ** argv)57 main(int argc, char **argv)
58 {
59 	static const kernel_ulong_t bogus_arg2 =
60 		(kernel_ulong_t) 0xdeadfacebadc0dedULL;
61 	static const kernel_ulong_t bogus_arg3 =
62 		(kernel_ulong_t) 0xdecafeedbeefda7eULL;
63 	static const struct {
64 		long arg;
65 		const char *str;
66 	} get_strs[] = {
67 		{ -1, "" },
68 		{ 0, " (PR_SPEC_NOT_AFFECTED)" },
69 		{ 1, " (PR_SPEC_PRCTL)" },
70 		{ 3, " (PR_SPEC_PRCTL|PR_SPEC_ENABLE)" },
71 		{ 8, " (PR_SPEC_FORCE_DISABLE)" },
72 		{ 16, " (0x10)" },
73 		{ 42, " (PR_SPEC_ENABLE|PR_SPEC_FORCE_DISABLE|0x20)" },
74 	};
75 	static const struct {
76 		kernel_ulong_t arg;
77 		const char *str;
78 	} set_strs[] = {
79 		{ 0, "0 /* PR_SPEC_??? */" },
80 		{ 1, "0x1 /* PR_SPEC_??? */" },
81 		{ 2, "PR_SPEC_ENABLE" },
82 		{ 3, "0x3 /* PR_SPEC_??? */" },
83 		{ 8, "PR_SPEC_FORCE_DISABLE" },
84 		{ 16, "0x10 /* PR_SPEC_??? */" },
85 		{ (kernel_ulong_t) 0xdecafeedbeefda7eULL, "0x"
86 # if SIZEOF_KERNEL_LONG_T == 8
87 			"decafeed"
88 # endif
89 			"beefda7e /* PR_SPEC_??? */" },
90 	};
91 
92 	long rc;
93 	const char *str = NULL;
94 
95 	if (argc < 2)
96 		error_msg_and_fail("Usage: %s INJECTED_VAL", argv[0]);
97 
98 	injected_val = strtol(argv[1], NULL, 0);
99 
100 	/* PR_GET_SPECULATION_CTRL */
101 	rc = do_prctl(52, 1, bogus_arg3);
102 	printf("prctl(PR_GET_SPECULATION_CTRL, 0x1 /* PR_SPEC_??? */) "
103 	       "= %s (INJECTED)\n", sprintrc(rc));
104 
105 	rc = do_prctl(52, bogus_arg2, bogus_arg3);
106 	printf("prctl(PR_GET_SPECULATION_CTRL, %#llx /* PR_SPEC_??? */) "
107 	       "= %s (INJECTED)\n",
108 	       (unsigned long long) bogus_arg2, sprintrc(rc));
109 
110 	rc = do_prctl(52, 0, bogus_arg3);
111 
112 	for (unsigned i = 0; i < ARRAY_SIZE(get_strs); i++) {
113 		if (get_strs[i].arg == rc) {
114 			str = get_strs[i].str;
115 			break;
116 		}
117 	}
118 	if (!str)
119 		error_msg_and_fail("Unknown return value: %ld", rc);
120 
121 	printf("prctl(PR_GET_SPECULATION_CTRL, PR_SPEC_STORE_BYPASS) "
122 	       "= %s%s (INJECTED)\n", sprintrc(rc), str);
123 
124 
125 	/* PR_SET_SPECULATION_CTRL*/
126 	rc = do_prctl(53, 1, bogus_arg3);
127 	printf("prctl(PR_SET_SPECULATION_CTRL, 0x1 /* PR_SPEC_??? */, %#llx) "
128 	       "= %s (INJECTED)\n",
129 	       (unsigned long long) bogus_arg3, sprintrc(rc));
130 
131 	rc = do_prctl(53, bogus_arg2, bogus_arg3);
132 	printf("prctl(PR_SET_SPECULATION_CTRL, %#llx /* PR_SPEC_??? */, %#llx) "
133 	       "= %s (INJECTED)\n",
134 	       (unsigned long long) bogus_arg2,
135 	       (unsigned long long) bogus_arg3,
136 	       sprintrc(rc));
137 
138 	for (unsigned i = 0; i < ARRAY_SIZE(set_strs); i++) {
139 		rc = do_prctl(53, 0, set_strs[i].arg);
140 		printf("prctl(PR_SET_SPECULATION_CTRL, PR_SPEC_STORE_BYPASS"
141 		       ", %s) = %s (INJECTED)\n",
142 		       set_strs[i].str, sprintrc(rc));
143 	}
144 
145 	puts("+++ exited with 0 +++");
146 	return 0;
147 }
148 
149 #else
150 
151 SKIP_MAIN_UNDEFINED("__NR_prctl")
152 
153 #endif
154