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/*
* Check decoding of prctl PR_GET_TID_ADDRESS operation.
*
* Copyright (c) 2016 Eugene Syromyatnikov <evgsyr@gmail.com>
* Copyright (c) 2016-2021 The strace developers.
* All rights reserved.
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "tests.h"
#include "scno.h"
#include <inttypes.h>
#include <stdio.h>
#include <unistd.h>
#include <linux/prctl.h>
static const char *
sprintaddr(kernel_ulong_t addr)
{
static char buf[sizeof("0x") + sizeof(addr) * 2];
if (addr) {
snprintf(buf, sizeof(buf), "%#llx", (unsigned long long) addr);
return buf;
}
return "NULL";
}
int
main(void)
{
static const kernel_ulong_t bogus_addr =
(kernel_ulong_t) 0xfffffffffffffffdULL;
/* Note that kernel puts kernel-sized pointer even on x32 */
TAIL_ALLOC_OBJECT_CONST_PTR(kernel_ulong_t, ptr);
long rc;
long set_ok;
prctl_marker();
*ptr = (kernel_ulong_t) 0xbadc0dedda7a1057ULL;
rc = syscall(__NR_prctl, PR_GET_TID_ADDRESS, NULL);
printf("prctl(PR_GET_TID_ADDRESS, NULL) = %s\n", sprintrc(rc));
rc = syscall(__NR_prctl, PR_GET_TID_ADDRESS, bogus_addr);
printf("prctl(PR_GET_TID_ADDRESS, %#llx) = %s\n",
(unsigned long long) bogus_addr, sprintrc(rc));
rc = syscall(__NR_prctl, PR_GET_TID_ADDRESS, ptr);
if (rc) {
printf("prctl(PR_GET_TID_ADDRESS, %p) = %s\n",
ptr, sprintrc(rc));
} else {
printf("prctl(PR_GET_TID_ADDRESS, [%s]) = %s\n",
sprintaddr(*ptr), sprintrc(rc));
}
set_ok = syscall(__NR_set_tid_address, bogus_addr);
rc = syscall(__NR_prctl, PR_GET_TID_ADDRESS, ptr);
if (rc) {
printf("prctl(PR_GET_TID_ADDRESS, %p) = %s\n",
ptr, sprintrc(rc));
} else {
printf("prctl(PR_GET_TID_ADDRESS, [%s]) = %s\n",
sprintaddr(set_ok ? bogus_addr : *ptr), sprintrc(rc));
}
puts("+++ exited with 0 +++");
return 0;
}
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