freebsd-nq/sys/boot/powerpc/kboot/hostdisk.c
Toomas Soome 1ecc859193 dosfs support in libstand is broken since r298230
Apparently the libstand dosfs optimization is a bit too optimistic
and did introduce possible memory corruption.

This patch is backing out the bad part and since this results in
dosfs reading full blocks now, we can also remove extra offset argument
from dv_strategy callback.

The analysis of the issue and the backout patch is provided by Mikhail Kupchik.

PR:		214423
Submitted by:	Mikhail Kupchik
Reported by:	Mikhail Kupchik
Reviewed by:	bapt, allanjude
Approved by:	allanjude (mentor)
MFC after:	1 month
Differential Revision:	https://reviews.freebsd.org/D8644
2016-12-30 19:06:29 +00:00

126 lines
3.0 KiB
C

/*-
* Copyright (C) 2014 Nathan Whitehorn
* 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 TOOLS GMBH 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <stdarg.h>
#include "bootstrap.h"
#include "host_syscall.h"
static int hostdisk_init(void);
static int hostdisk_strategy(void *devdata, int flag, daddr_t dblk,
size_t size, char *buf, size_t *rsize);
static int hostdisk_open(struct open_file *f, ...);
static int hostdisk_close(struct open_file *f);
static int hostdisk_ioctl(struct open_file *f, u_long cmd, void *data);
static int hostdisk_print(int verbose);
struct devsw hostdisk = {
"/dev",
DEVT_DISK,
hostdisk_init,
hostdisk_strategy,
hostdisk_open,
hostdisk_close,
hostdisk_ioctl,
hostdisk_print,
};
static int
hostdisk_init(void)
{
return (0);
}
static int
hostdisk_strategy(void *devdata, int flag, daddr_t dblk, size_t size,
char *buf, size_t *rsize)
{
struct devdesc *desc = devdata;
daddr_t pos;
int n;
pos = dblk * 512;
if (host_seek(desc->d_unit, pos, 0) < 0) {
printf("Seek error\n");
return (EIO);
}
n = host_read(desc->d_unit, buf, size);
if (n < 0)
return (EIO);
*rsize = n;
return (0);
}
static int
hostdisk_open(struct open_file *f, ...)
{
struct devdesc *desc;
va_list vl;
va_start(vl, f);
desc = va_arg(vl, struct devdesc *);
va_end(vl);
desc->d_unit = host_open(desc->d_opendata, O_RDONLY, 0);
if (desc->d_unit <= 0) {
printf("hostdisk_open: couldn't open %s: %d\n",
desc->d_opendata, desc->d_unit);
return (ENOENT);
}
return (0);
}
static int
hostdisk_close(struct open_file *f)
{
struct devdesc *desc = f->f_devdata;
host_close(desc->d_unit);
return (0);
}
static int
hostdisk_ioctl(struct open_file *f, u_long cmd, void *data)
{
return (EINVAL);
}
static int
hostdisk_print(int verbose)
{
return (0);
}