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/*
* Check decoding of prctl PR_GET_MDWE/PR_SET_MDWE operations.
*
* Copyright (c) 2021-2023 The strace developers.
* All rights reserved.
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "tests.h"
#include "scno.h"
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <linux/prctl.h>
static long injected_val;
static long
do_prctl(kernel_ulong_t cmd, kernel_ulong_t arg2, kernel_ulong_t arg3,
kernel_ulong_t arg4, kernel_ulong_t arg5)
{
long rc = syscall(__NR_prctl, cmd, arg2, arg3, arg4, arg5);
if (rc != injected_val) {
error_msg_and_fail("Return value (%ld) differs from expected "
"injected value (%ld)",
rc, injected_val);
}
return rc;
}
int
main(int argc, char **argv)
{
static const kernel_ulong_t bogus_arg2 =
(kernel_ulong_t) 0xdecafeedbeefda7eULL;
static const kernel_ulong_t bogus_arg3 =
(kernel_ulong_t) 0xbadc0dedfacef00dULL;
static const kernel_ulong_t bogus_arg4 =
(kernel_ulong_t) 0xcafeda7efeedbeefULL;
static const kernel_ulong_t bogus_arg5 =
(kernel_ulong_t) 0xfa57beeffacefeedULL;
static const struct {
long arg;
const char *str;
} get_strs[] = {
{-1, ""},
{0, ""},
{1, " (PR_MDWE_REFUSE_EXEC_GAIN)"},
{2, " (PR_MDWE_NO_INHERIT)"},
{3, " (PR_MDWE_REFUSE_EXEC_GAIN|PR_MDWE_NO_INHERIT)"},
{4, ""},
{5, " (PR_MDWE_REFUSE_EXEC_GAIN|0x4)"},
{0x7ea1cafc, ""},
};
static const struct {
kernel_ulong_t arg;
const char *str;
} set_strs[] = {
{0, "0"},
{1, "PR_MDWE_REFUSE_EXEC_GAIN"},
{2, "PR_MDWE_NO_INHERIT"},
{3, "PR_MDWE_REFUSE_EXEC_GAIN|PR_MDWE_NO_INHERIT"},
{4, "0x4 /* PR_MDWE_??? */"},
{5, "PR_MDWE_REFUSE_EXEC_GAIN|0x4"},
{0x7ea1cafc, "0x7ea1cafc /* PR_MDWE_??? */"}
};
long rc;
unsigned long num_skip;
const char *str = NULL;
bool locked = false;
if (argc < 3)
error_msg_and_fail("Usage: %s NUM_SKIP INJECT_RETVAL", argv[0]);
num_skip = strtoul(argv[1], NULL, 0);
injected_val = strtol(argv[2], NULL, 0);
for (size_t i = 0; i < num_skip; i++) {
if ((prctl_marker() != injected_val) ||
((injected_val == -1) && (errno != ENOTTY)))
continue;
locked = true;
break;
}
if (!locked)
error_msg_and_fail("Have not locked on prctl(-1, -2, -3, -4"
", -5) returning %ld", injected_val);
/* PR_GET_MDWE */
for (unsigned int j = 0; j < 2; j++) {
if (j) {
rc = do_prctl(PR_GET_MDWE, bogus_arg2, bogus_arg3,
bogus_arg4, bogus_arg5);
} else {
rc = do_prctl(PR_GET_MDWE, 0, 0, 0, 0);
}
const char *errstr = sprintrc(rc);
for (size_t i = 0; i < ARRAY_SIZE(get_strs); i++) {
if (get_strs[i].arg == rc) {
str = get_strs[i].str;
break;
}
}
if (!str)
error_msg_and_fail("Unknown return value: %ld", rc);
printf("prctl(PR_GET_MDWE, %s) = ", j ?
#if SIZEOF_KERNEL_LONG_T > 4
"0xdecafeedbeefda7e, 0xbadc0dedfacef00d"
", 0xcafeda7efeedbeef, 0xfa57beeffacefeed"
#else
"0xbeefda7e, 0xfacef00d, 0xfeedbeef, 0xfacefeed"
#endif
: "0, 0, 0, 0");
if (rc < 0)
printf("%s", errstr);
else
printf("%#lx", rc);
printf("%s (INJECTED)\n", str);
}
/* PR_SET_FP_MODE */
for (size_t i = 0; i < ARRAY_SIZE(set_strs); i++) {
rc = do_prctl(PR_SET_MDWE, set_strs[i].arg, 0, 0, 0);
printf("prctl(PR_SET_MDWE, %s, 0, 0, 0) = %s (INJECTED)\n",
set_strs[i].str, sprintrc(rc));
rc = do_prctl(PR_SET_MDWE, set_strs[i].arg,
bogus_arg3, bogus_arg4, bogus_arg5);
printf("prctl(PR_SET_MDWE, %s, %s) = %s (INJECTED)\n",
set_strs[i].str,
#if SIZEOF_KERNEL_LONG_T > 4
"0xbadc0dedfacef00d, 0xcafeda7efeedbeef"
", 0xfa57beeffacefeed"
#else
"0xfacef00d, 0xfeedbeef, 0xfacefeed"
#endif
, sprintrc(rc));
}
puts("+++ exited with 0 +++");
return 0;
}
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