mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-11-16 17:58:23 +00:00
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>
87 lines
2.3 KiB
C
87 lines
2.3 KiB
C
/*
|
|
* (C) Copyright 2005
|
|
* 2N Telekomunikace, Ladislav Michl <michl@2n.cz>
|
|
*
|
|
* 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 <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <stdint.h>
|
|
#include <fcntl.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
#include <sys/types.h>
|
|
#include <sys/stat.h>
|
|
#include "crcek.h"
|
|
|
|
extern uint32_t crc32(uint32_t, const unsigned char *, uint);
|
|
|
|
static uint32_t data[LOADER_SIZE/4 + 3];
|
|
|
|
static int do_crc(char *path, unsigned version)
|
|
{
|
|
uint32_t *p;
|
|
ssize_t size;
|
|
int fd;
|
|
|
|
fd = open(path, O_RDONLY);
|
|
if (fd == -1) {
|
|
perror("Error opening file");
|
|
return EXIT_FAILURE;
|
|
}
|
|
p = data + 2;
|
|
size = read(fd, p, LOADER_SIZE + 4);
|
|
if (size == -1) {
|
|
perror("Error reading file");
|
|
return EXIT_FAILURE;
|
|
}
|
|
if (size > LOADER_SIZE) {
|
|
fprintf(stderr, "File too large\n");
|
|
return EXIT_FAILURE;
|
|
}
|
|
size = (size + 3) & ~3; /* round up to 4 bytes */
|
|
size += 4; /* add size of version field */
|
|
data[0] = size;
|
|
data[1] = version;
|
|
data[size/4 + 1] = crc32(0, (unsigned char *)(data + 1), size);
|
|
close(fd);
|
|
|
|
if (write(STDOUT_FILENO, data, size + 4 /*size*/ + 4 /*crc*/) == -1) {
|
|
perror("Error writing file");
|
|
return EXIT_FAILURE;
|
|
}
|
|
|
|
return EXIT_SUCCESS;
|
|
}
|
|
|
|
int main(int argc, char * const *argv)
|
|
{
|
|
if (argc == 2) {
|
|
return do_crc(argv[1], 0);
|
|
} else if ((argc == 4) && (strcmp(argv[1], "-v") == 0)) {
|
|
char *endptr, *nptr = argv[2];
|
|
unsigned ver = strtoul(nptr, &endptr, 0);
|
|
if (*nptr != '\0' && *endptr == '\0')
|
|
return do_crc(argv[3], ver);
|
|
}
|
|
fprintf(stderr, "Usage: crcit [-v version] <image>\n");
|
|
|
|
return EXIT_FAILURE;
|
|
}
|