mirror of
https://github.com/brain-hackers/u-boot-brain
synced 2024-06-09 23:36:03 +09:00
54841ab50c
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>
147 lines
3.6 KiB
C
147 lines
3.6 KiB
C
/*
|
|
* (C) Copyright 2002
|
|
* Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com
|
|
*
|
|
* 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
|
|
*/
|
|
|
|
/*
|
|
* SPI Read/Write Utilities
|
|
*/
|
|
|
|
#include <common.h>
|
|
#include <command.h>
|
|
#include <spi.h>
|
|
|
|
/*-----------------------------------------------------------------------
|
|
* Definitions
|
|
*/
|
|
|
|
#ifndef MAX_SPI_BYTES
|
|
# define MAX_SPI_BYTES 32 /* Maximum number of bytes we can handle */
|
|
#endif
|
|
|
|
#ifndef CONFIG_DEFAULT_SPI_BUS
|
|
# define CONFIG_DEFAULT_SPI_BUS 0
|
|
#endif
|
|
#ifndef CONFIG_DEFAULT_SPI_MODE
|
|
# define CONFIG_DEFAULT_SPI_MODE SPI_MODE_0
|
|
#endif
|
|
|
|
/*
|
|
* Values from last command.
|
|
*/
|
|
static unsigned int device;
|
|
static int bitlen;
|
|
static uchar dout[MAX_SPI_BYTES];
|
|
static uchar din[MAX_SPI_BYTES];
|
|
|
|
/*
|
|
* SPI read/write
|
|
*
|
|
* Syntax:
|
|
* spi {dev} {num_bits} {dout}
|
|
* {dev} is the device number for controlling chip select (see TBD)
|
|
* {num_bits} is the number of bits to send & receive (base 10)
|
|
* {dout} is a hexadecimal string of data to send
|
|
* The command prints out the hexadecimal string received via SPI.
|
|
*/
|
|
|
|
int do_spi (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
|
|
{
|
|
struct spi_slave *slave;
|
|
char *cp = 0;
|
|
uchar tmp;
|
|
int j;
|
|
int rcode = 0;
|
|
|
|
/*
|
|
* We use the last specified parameters, unless new ones are
|
|
* entered.
|
|
*/
|
|
|
|
if ((flag & CMD_FLAG_REPEAT) == 0)
|
|
{
|
|
if (argc >= 2)
|
|
device = simple_strtoul(argv[1], NULL, 10);
|
|
if (argc >= 3)
|
|
bitlen = simple_strtoul(argv[2], NULL, 10);
|
|
if (argc >= 4) {
|
|
cp = argv[3];
|
|
for(j = 0; *cp; j++, cp++) {
|
|
tmp = *cp - '0';
|
|
if(tmp > 9)
|
|
tmp -= ('A' - '0') - 10;
|
|
if(tmp > 15)
|
|
tmp -= ('a' - 'A');
|
|
if(tmp > 15) {
|
|
printf("Hex conversion error on %c, giving up.\n", *cp);
|
|
return 1;
|
|
}
|
|
if((j % 2) == 0)
|
|
dout[j / 2] = (tmp << 4);
|
|
else
|
|
dout[j / 2] |= tmp;
|
|
}
|
|
}
|
|
}
|
|
|
|
if ((bitlen < 0) || (bitlen > (MAX_SPI_BYTES * 8))) {
|
|
printf("Invalid bitlen %d, giving up.\n", bitlen);
|
|
return 1;
|
|
}
|
|
|
|
/* FIXME: Make these parameters run-time configurable */
|
|
slave = spi_setup_slave(CONFIG_DEFAULT_SPI_BUS, device, 1000000,
|
|
CONFIG_DEFAULT_SPI_MODE);
|
|
if (!slave) {
|
|
printf("Invalid device %d, giving up.\n", device);
|
|
return 1;
|
|
}
|
|
|
|
debug ("spi chipsel = %08X\n", device);
|
|
|
|
spi_claim_bus(slave);
|
|
if(spi_xfer(slave, bitlen, dout, din,
|
|
SPI_XFER_BEGIN | SPI_XFER_END) != 0) {
|
|
printf("Error with the SPI transaction.\n");
|
|
rcode = 1;
|
|
} else {
|
|
for(j = 0; j < ((bitlen + 7) / 8); j++) {
|
|
printf("%02X", din[j]);
|
|
}
|
|
printf("\n");
|
|
}
|
|
spi_release_bus(slave);
|
|
spi_free_slave(slave);
|
|
|
|
return rcode;
|
|
}
|
|
|
|
/***************************************************/
|
|
|
|
U_BOOT_CMD(
|
|
sspi, 5, 1, do_spi,
|
|
"SPI utility commands",
|
|
"<device> <bit_len> <dout> - Send <bit_len> bits from <dout> out the SPI\n"
|
|
"<device> - Identifies the chip select of the device\n"
|
|
"<bit_len> - Number of bits to send (base 10)\n"
|
|
"<dout> - Hexadecimal string that gets sent"
|
|
);
|