HardenedBSD/libexec/rtld-elf/xmalloc.c
Konstantin Belousov 2f06c66ad5 Make p_vaddr % p_align == p_offset % p_align for (some) TLS segments.
See https://sourceware.org/bugzilla/show_bug.cgi?id=24606 for the test case.
See https://reviews.llvm.org/D64930 for the background and more discussion.

Also this fixes another bug in malloc_aligned() where total size of
the allocated memory might be not enough to fit the aligned requested
block after the initial pointer is incremented by the pointer size.

Reviewed by:	bdragon
Tested by:	antoine (exp-run PR 244866), bdragon, emaste
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
Differential revision:	https://reviews.freebsd.org/D21163
2020-04-04 22:37:50 +00:00

111 lines
2.6 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* 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 <sys/param.h>
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "rtld.h"
#include "rtld_printf.h"
#include "rtld_malloc.h"
#include "rtld_libc.h"
void *
xcalloc(size_t number, size_t size)
{
void *p;
p = __crt_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;
p = __crt_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, size_t offset)
{
char *mem, *res;
uintptr_t x;
offset &= align - 1;
if (align < sizeof(void *))
align = sizeof(void *);
mem = xmalloc(size + 3 * align + offset);
x = roundup((uintptr_t)mem + sizeof(void *), align);
x += offset;
res = (void *)x;
x -= sizeof(void *);
memcpy((void *)x, &mem, sizeof(mem));
return (res);
}
void
free_aligned(void *ptr)
{
void *mem;
uintptr_t x;
if (ptr == NULL)
return;
x = (uintptr_t)ptr;
x -= sizeof(void *);
memcpy(&mem, (void *)x, sizeof(mem));
free(mem);
}