u-boot/arch/mips/cpu/cpu.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

112 lines
2.7 KiB
C

/*
* (C) Copyright 2003
* Wolfgang Denk, DENX Software Engineering, <wd@denx.de>
*
* See file CREDITS for list of people who contributed to this
* project.
*
* 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 <netdev.h>
#include <asm/mipsregs.h>
#include <asm/cacheops.h>
#include <asm/reboot.h>
#define cache_op(op,addr) \
__asm__ __volatile__( \
" .set push \n" \
" .set noreorder \n" \
" .set mips3\n\t \n" \
" cache %0, %1 \n" \
" .set pop \n" \
: \
: "i" (op), "R" (*(unsigned char *)(addr)))
void __attribute__((weak)) _machine_restart(void)
{
}
int do_reset(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
_machine_restart();
fprintf(stderr, "*** reset failed ***\n");
return 0;
}
void flush_cache(ulong start_addr, ulong size)
{
unsigned long lsize = CONFIG_SYS_CACHELINE_SIZE;
unsigned long addr = start_addr & ~(lsize - 1);
unsigned long aend = (start_addr + size - 1) & ~(lsize - 1);
while (1) {
cache_op(Hit_Writeback_Inv_D, addr);
cache_op(Hit_Invalidate_I, addr);
if (addr == aend)
break;
addr += lsize;
}
}
void flush_dcache_range(ulong start_addr, ulong stop)
{
unsigned long lsize = CONFIG_SYS_CACHELINE_SIZE;
unsigned long addr = start_addr & ~(lsize - 1);
unsigned long aend = (stop - 1) & ~(lsize - 1);
while (1) {
cache_op(Hit_Writeback_Inv_D, addr);
if (addr == aend)
break;
addr += lsize;
}
}
void invalidate_dcache_range(ulong start_addr, ulong stop)
{
unsigned long lsize = CONFIG_SYS_CACHELINE_SIZE;
unsigned long addr = start_addr & ~(lsize - 1);
unsigned long aend = (stop - 1) & ~(lsize - 1);
while (1) {
cache_op(Hit_Invalidate_D, addr);
if (addr == aend)
break;
addr += lsize;
}
}
void write_one_tlb(int index, u32 pagemask, u32 hi, u32 low0, u32 low1)
{
write_c0_entrylo0(low0);
write_c0_pagemask(pagemask);
write_c0_entrylo1(low1);
write_c0_entryhi(hi);
write_c0_index(index);
tlb_write_indexed();
}
int cpu_eth_init(bd_t *bis)
{
#ifdef CONFIG_SOC_AU1X00
au1x00_enet_initialize(bis);
#endif
return 0;
}