u-boot/arch/arm/lib/bootm.c
Wolfgang Denk 54841ab50c Make sure that argv[] argument pointers are not modified.
The hush shell dynamically allocates (and re-allocates) memory for the
argument strings in the "char *argv[]" argument vector passed to
commands.  Any code that modifies these pointers will cause serious
corruption of the malloc data structures and crash U-Boot, so make
sure the compiler can check that no such modifications are being done
by changing the code into "char * const argv[]".

This modification is the result of debugging a strange crash caused
after adding a new command, which used the following argument
processing code which has been working perfectly fine in all Unix
systems since version 6 - but not so in U-Boot:

int main (int argc, char **argv)
{
	while (--argc > 0 && **++argv == '-') {
/* ====> */	while (*++*argv) {
			switch (**argv) {
			case 'd':
				debug++;
				break;
			...
			default:
				usage ();
			}
		}
	}
	...
}

The line marked "====>" will corrupt the malloc data structures and
usually cause U-Boot to crash when the next command gets executed by
the shell.  With the modification, the compiler will prevent this with
an
	error: increment of read-only location '*argv'

N.B.: The code above can be trivially rewritten like this:

	while (--argc > 0 && **++argv == '-') {
		char *arg = *argv;
		while (*++arg) {
			switch (*arg) {
			...

Signed-off-by: Wolfgang Denk <wd@denx.de>
Acked-by: Mike Frysinger <vapier@gentoo.org>
2010-07-04 23:55:42 +02:00

242 lines
5.9 KiB
C

/*
* (C) Copyright 2002
* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Marius Groeger <mgroeger@sysgo.de>
*
* Copyright (C) 2001 Erik Mouw (J.A.K.Mouw@its.tudelft.nl)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <common.h>
#include <command.h>
#include <image.h>
#include <u-boot/zlib.h>
#include <asm/byteorder.h>
DECLARE_GLOBAL_DATA_PTR;
#if defined (CONFIG_SETUP_MEMORY_TAGS) || \
defined (CONFIG_CMDLINE_TAG) || \
defined (CONFIG_INITRD_TAG) || \
defined (CONFIG_SERIAL_TAG) || \
defined (CONFIG_REVISION_TAG)
static void setup_start_tag (bd_t *bd);
# ifdef CONFIG_SETUP_MEMORY_TAGS
static void setup_memory_tags (bd_t *bd);
# endif
static void setup_commandline_tag (bd_t *bd, char *commandline);
# ifdef CONFIG_INITRD_TAG
static void setup_initrd_tag (bd_t *bd, ulong initrd_start,
ulong initrd_end);
# endif
static void setup_end_tag (bd_t *bd);
static struct tag *params;
#endif /* CONFIG_SETUP_MEMORY_TAGS || CONFIG_CMDLINE_TAG || CONFIG_INITRD_TAG */
int do_bootm_linux(int flag, int argc, char * const argv[], bootm_headers_t *images)
{
bd_t *bd = gd->bd;
char *s;
int machid = bd->bi_arch_number;
void (*theKernel)(int zero, int arch, uint params);
#ifdef CONFIG_CMDLINE_TAG
char *commandline = getenv ("bootargs");
#endif
if ((flag != 0) && (flag != BOOTM_STATE_OS_GO))
return 1;
theKernel = (void (*)(int, int, uint))images->ep;
s = getenv ("machid");
if (s) {
machid = simple_strtoul (s, NULL, 16);
printf ("Using machid 0x%x from environment\n", machid);
}
show_boot_progress (15);
debug ("## Transferring control to Linux (at address %08lx) ...\n",
(ulong) theKernel);
#if defined (CONFIG_SETUP_MEMORY_TAGS) || \
defined (CONFIG_CMDLINE_TAG) || \
defined (CONFIG_INITRD_TAG) || \
defined (CONFIG_SERIAL_TAG) || \
defined (CONFIG_REVISION_TAG)
setup_start_tag (bd);
#ifdef CONFIG_SERIAL_TAG
setup_serial_tag (&params);
#endif
#ifdef CONFIG_REVISION_TAG
setup_revision_tag (&params);
#endif
#ifdef CONFIG_SETUP_MEMORY_TAGS
setup_memory_tags (bd);
#endif
#ifdef CONFIG_CMDLINE_TAG
setup_commandline_tag (bd, commandline);
#endif
#ifdef CONFIG_INITRD_TAG
if (images->rd_start && images->rd_end)
setup_initrd_tag (bd, images->rd_start, images->rd_end);
#endif
setup_end_tag (bd);
#endif
/* we assume that the kernel is in place */
printf ("\nStarting kernel ...\n\n");
#ifdef CONFIG_USB_DEVICE
{
extern void udc_disconnect (void);
udc_disconnect ();
}
#endif
cleanup_before_linux ();
theKernel (0, machid, bd->bi_boot_params);
/* does not return */
return 1;
}
#if defined (CONFIG_SETUP_MEMORY_TAGS) || \
defined (CONFIG_CMDLINE_TAG) || \
defined (CONFIG_INITRD_TAG) || \
defined (CONFIG_SERIAL_TAG) || \
defined (CONFIG_REVISION_TAG)
static void setup_start_tag (bd_t *bd)
{
params = (struct tag *) bd->bi_boot_params;
params->hdr.tag = ATAG_CORE;
params->hdr.size = tag_size (tag_core);
params->u.core.flags = 0;
params->u.core.pagesize = 0;
params->u.core.rootdev = 0;
params = tag_next (params);
}
#ifdef CONFIG_SETUP_MEMORY_TAGS
static void setup_memory_tags (bd_t *bd)
{
int i;
for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
params->hdr.tag = ATAG_MEM;
params->hdr.size = tag_size (tag_mem32);
params->u.mem.start = bd->bi_dram[i].start;
params->u.mem.size = bd->bi_dram[i].size;
params = tag_next (params);
}
}
#endif /* CONFIG_SETUP_MEMORY_TAGS */
static void setup_commandline_tag (bd_t *bd, char *commandline)
{
char *p;
if (!commandline)
return;
/* eat leading white space */
for (p = commandline; *p == ' '; p++);
/* skip non-existent command lines so the kernel will still
* use its default command line.
*/
if (*p == '\0')
return;
params->hdr.tag = ATAG_CMDLINE;
params->hdr.size =
(sizeof (struct tag_header) + strlen (p) + 1 + 4) >> 2;
strcpy (params->u.cmdline.cmdline, p);
params = tag_next (params);
}
#ifdef CONFIG_INITRD_TAG
static void setup_initrd_tag (bd_t *bd, ulong initrd_start, ulong initrd_end)
{
/* an ATAG_INITRD node tells the kernel where the compressed
* ramdisk can be found. ATAG_RDIMG is a better name, actually.
*/
params->hdr.tag = ATAG_INITRD2;
params->hdr.size = tag_size (tag_initrd);
params->u.initrd.start = initrd_start;
params->u.initrd.size = initrd_end - initrd_start;
params = tag_next (params);
}
#endif /* CONFIG_INITRD_TAG */
#ifdef CONFIG_SERIAL_TAG
void setup_serial_tag (struct tag **tmp)
{
struct tag *params = *tmp;
struct tag_serialnr serialnr;
void get_board_serial(struct tag_serialnr *serialnr);
get_board_serial(&serialnr);
params->hdr.tag = ATAG_SERIAL;
params->hdr.size = tag_size (tag_serialnr);
params->u.serialnr.low = serialnr.low;
params->u.serialnr.high= serialnr.high;
params = tag_next (params);
*tmp = params;
}
#endif
#ifdef CONFIG_REVISION_TAG
void setup_revision_tag(struct tag **in_params)
{
u32 rev = 0;
u32 get_board_rev(void);
rev = get_board_rev();
params->hdr.tag = ATAG_REVISION;
params->hdr.size = tag_size (tag_revision);
params->u.revision.rev = rev;
params = tag_next (params);
}
#endif /* CONFIG_REVISION_TAG */
static void setup_end_tag (bd_t *bd)
{
params->hdr.tag = ATAG_NONE;
params->hdr.size = 0;
}
#endif /* CONFIG_SETUP_MEMORY_TAGS || CONFIG_CMDLINE_TAG || CONFIG_INITRD_TAG */