freebsd-skq/libexec/rtld-elf/xmalloc.c
davidxu ea93c12602 malloc_aligned() may not leave enough space for pointer to allocated memory,
saving the pointer will overwrite bytes belongs to another memory block
unexpectly, to fix the problem, use (allocated address + sizeof(void *)) as
initial value, and slip to next aligned address, so maximum extra bytes is
sizeof(void *) + align - 1.

Tested by: Andre Albsmeier < mail at ma17 dot ata dot myota dot orgndre >
2014-02-21 03:36:16 +00:00

100 lines
2.4 KiB
C

/*-
* Copyright 1996-1998 John D. Polstra.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "rtld.h"
#include "rtld_printf.h"
void *
xcalloc(size_t number, size_t size)
{
void *p;
p = calloc(number, size);
if (p == NULL) {
rtld_fdputstr(STDERR_FILENO, "Out of memory\n");
_exit(1);
}
return (p);
}
void *
xmalloc(size_t size)
{
void *p = malloc(size);
if (p == NULL) {
rtld_fdputstr(STDERR_FILENO, "Out of memory\n");
_exit(1);
}
return p;
}
char *
xstrdup(const char *str)
{
char *copy;
size_t len;
len = strlen(str) + 1;
copy = xmalloc(len);
memcpy(copy, str, len);
return (copy);
}
void *
malloc_aligned(size_t size, size_t align)
{
void *mem, *res;
if (align & (sizeof(void *) -1)) {
rtld_fdputstr(STDERR_FILENO, "Invalid alignment\n");
_exit(1);
}
mem = xmalloc(size + sizeof(void *) + align - 1);
res = (void *)round((uintptr_t)mem + sizeof(void *), align);
*(void **)((uintptr_t)res - sizeof(void *)) = mem;
return (res);
}
void
free_aligned(void *ptr)
{
void *mem;
uintptr_t x;
if (ptr == NULL)
return;
x = (uintptr_t)ptr;
x -= sizeof(void *);
mem = *(void **)x;
free(mem);
}