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/* Unit test for _dl_addr_inside_object.
Copyright (C) 2016-2021 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <stdio.h>
#include <stdlib.h>
#include <link.h>
#include <elf.h>
#include <libc-symbols.h>
extern int _dl_addr_inside_object (struct link_map *l, const ElfW(Addr) addr);
static int
do_test (void)
{
int ret, err = 0;
ElfW(Addr) addr;
struct link_map map;
ElfW(Phdr) header;
map.l_phdr = &header;
map.l_phnum = 1;
map.l_addr = 0x0;
/* Segment spans 0x2000 -> 0x4000. */
header.p_vaddr = 0x2000;
header.p_memsz = 0x2000;
header.p_type = PT_LOAD;
/* Address is above the segment e.g. > 0x4000. */
addr = 0x5000;
ret = _dl_addr_inside_object (&map, addr);
switch (ret)
{
case 0:
printf ("PASS: Above: Address is detected as outside the segment.\n");
break;
case 1:
printf ("FAIL: Above: Address is detected as inside the segment.\n");
err++;
break;
default:
printf ("FAIL: Above: Invalid return value.\n");
exit (1);
}
/* Address is inside the segment e.g. 0x2000 < addr < 0x4000. */
addr = 0x3000;
ret = _dl_addr_inside_object (&map, addr);
switch (ret)
{
case 0:
printf ("FAIL: Inside: Address is detected as outside the segment.\n");
err++;
break;
case 1:
printf ("PASS: Inside: Address is detected as inside the segment.\n");
break;
default:
printf ("FAIL: Inside: Invalid return value.\n");
exit (1);
}
/* Address is below the segment e.g. < 0x2000. */
addr = 0x1000;
ret = _dl_addr_inside_object (&map, addr);
switch (ret)
{
case 0:
printf ("PASS: Below: Address is detected as outside the segment.\n");
break;
case 1:
printf ("FAIL: Below: Address is detected as inside the segment.\n");
err++;
break;
default:
printf ("FAIL: Below: Invalid return value.\n");
exit (1);
}
/* Address is in the segment and addr == p_vaddr. */
addr = 0x2000;
ret = _dl_addr_inside_object (&map, addr);
switch (ret)
{
case 0:
printf ("FAIL: At p_vaddr: Address is detected as outside the segment.\n");
err++;
break;
case 1:
printf ("PASS: At p_vaddr: Address is detected as inside the segment.\n");
break;
default:
printf ("FAIL: At p_vaddr: Invalid return value.\n");
exit (1);
}
/* Address is in the segment and addr == p_vaddr + p_memsz - 1. */
addr = 0x2000 + 0x2000 - 0x1;
ret = _dl_addr_inside_object (&map, addr);
switch (ret)
{
case 0:
printf ("FAIL: At p_memsz-1: Address is detected as outside the segment.\n");
err++;
break;
case 1:
printf ("PASS: At p_memsz-1: Address is detected as inside the segment.\n");
break;
default:
printf ("FAIL: At p_memsz-1: Invalid return value.\n");
exit (1);
}
/* Address is outside the segment and addr == p_vaddr + p_memsz. */
addr = 0x2000 + 0x2000;
ret = _dl_addr_inside_object (&map, addr);
switch (ret)
{
case 0:
printf ("PASS: At p_memsz: Address is detected as outside the segment.\n");
break;
case 1:
printf ("FAIL: At p_memsz: Address is detected as inside the segment.\n");
err++;
break;
default:
printf ("FAIL: At p_memsz: Invalid return value.\n");
exit (1);
}
/* Address is outside the segment and p_vaddr at maximum address. */
addr = 0x0 - 0x2;
header.p_vaddr = 0x0 - 0x1;
header.p_memsz = 0x1;
ret = _dl_addr_inside_object (&map, addr);
switch (ret)
{
case 0:
printf ("PASS: At max: Address is detected as outside the segment.\n");
break;
case 1:
printf ("FAIL: At max: Address is detected as inside the segment.\n");
err++;
break;
default:
printf ("FAIL: At max: Invalid return value.\n");
exit (1);
}
/* Address is outside the segment and p_vaddr at minimum address. */
addr = 0x1;
header.p_vaddr = 0x0;
header.p_memsz = 0x1;
ret = _dl_addr_inside_object (&map, addr);
switch (ret)
{
case 0:
printf ("PASS: At min: Address is detected as outside the segment.\n");
break;
case 1:
printf ("FAIL: At min: Address is detected as inside the segment.\n");
err++;
break;
default:
printf ("FAIL: At min: Invalid return value.\n");
exit (1);
}
/* Address is always inside the segment with p_memsz at max. */
addr = 0x0;
header.p_vaddr = 0x0;
header.p_memsz = 0x0 - 0x1;
ret = _dl_addr_inside_object (&map, addr);
switch (ret)
{
case 0:
printf ("FAIL: At maxmem: Address is detected as outside the segment.\n");
err++;
break;
case 1:
printf ("PASS: At maxmem: Address is detected as inside the segment.\n");
break;
default:
printf ("FAIL: At maxmem: Invalid return value.\n");
exit (1);
}
/* Attempt to wrap addr into the segment.
Pick a load address in the middle of the address space.
Place the test address at 0x0 so it wraps to the middle again. */
map.l_addr = 0x0 - 0x1;
map.l_addr = map.l_addr / 2;
addr = 0;
/* Setup a segment covering 1/2 the address space. */
header.p_vaddr = 0x0;
header.p_memsz = 0x0 - 0x1 - map.l_addr;
/* No matter where you place addr everything is shifted modulo l_addr
and even with this underflow you're always 1 byte away from being
in the range. */
ret = _dl_addr_inside_object (&map, addr);
switch (ret)
{
case 0:
printf ("PASS: Underflow: Address is detected as outside the segment.\n");
break;
case 1:
printf ("FAIL: Underflow: Address is detected as inside the segment.\n");
err++;
break;
default:
printf ("FAIL: Underflow: Invalid return value.\n");
exit (1);
}
return err;
}
#include <support/test-driver.c>
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