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>
diff --git a/board/freescale/common/ngpixis.c b/board/freescale/common/ngpixis.c
index bb6794e..a135fbe 100644
--- a/board/freescale/common/ngpixis.c
+++ b/board/freescale/common/ngpixis.c
@@ -92,7 +92,7 @@
}
-int pixis_reset_cmd(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
+int pixis_reset_cmd(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
unsigned int i;
char *p_altbank = NULL;
diff --git a/board/freescale/common/pixis.c b/board/freescale/common/pixis.c
index 119eaf9..a35b5cf 100644
--- a/board/freescale/common/pixis.c
+++ b/board/freescale/common/pixis.c
@@ -284,7 +284,7 @@
*
*/
static int pixis_disable_watchdog_cmd(cmd_tbl_t *cmdtp, int flag, int argc,
- char *argv[])
+ char * const argv[])
{
/* Disable the VELA sequencer and the watchdog */
clrbits_8(pixis_base + PIXIS_VCTL, 9);
@@ -302,7 +302,7 @@
/* Enable or disable SGMII mode for a TSEC
*/
-static int pixis_set_sgmii(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
+static int pixis_set_sgmii(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
int which_tsec = -1;
unsigned char mask;
@@ -430,7 +430,7 @@
return intval + decval;
}
-static int pixis_reset_cmd(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
+static int pixis_reset_cmd(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
unsigned int i;
char *p_cf = NULL;
diff --git a/board/freescale/common/sys_eeprom.c b/board/freescale/common/sys_eeprom.c
index 661015e..5a8f4f5 100644
--- a/board/freescale/common/sys_eeprom.c
+++ b/board/freescale/common/sys_eeprom.c
@@ -314,7 +314,7 @@
update_crc();
}
-int do_mac(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
+int do_mac(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
char cmd;