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/esd/common/auto_update.c b/board/esd/common/auto_update.c
index c4a49e2..4dfea71 100644
--- a/board/esd/common/auto_update.c
+++ b/board/esd/common/auto_update.c
@@ -492,7 +492,7 @@
return 0;
}
-int auto_update(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
+int auto_update(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
do_auto_update();
diff --git a/board/esd/common/cmd_loadpci.c b/board/esd/common/cmd_loadpci.c
index eecae0a..87da27d 100644
--- a/board/esd/common/cmd_loadpci.c
+++ b/board/esd/common/cmd_loadpci.c
@@ -37,7 +37,7 @@
/*
* Command loadpci: wait for signal from host and boot image.
*/
-int do_loadpci(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
+int do_loadpci(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
u32 *ptr = 0;
int count = 0;
diff --git a/board/esd/common/lcd.c b/board/esd/common/lcd.c
index 5c50b4c..9109b64 100644
--- a/board/esd/common/lcd.c
+++ b/board/esd/common/lcd.c
@@ -339,7 +339,7 @@
return lcd_bmp(logo_bmp);
}
-int do_esdbmp(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
+int do_esdbmp(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
ulong addr;
#ifdef CONFIG_VIDEO_SM501
diff --git a/board/esd/common/xilinx_jtag/micro.c b/board/esd/common/xilinx_jtag/micro.c
index 414e821..9823e5e 100644
--- a/board/esd/common/xilinx_jtag/micro.c
+++ b/board/esd/common/xilinx_jtag/micro.c
@@ -1828,7 +1828,7 @@
* ppzArgv - array of ptrs to strings (command-line arguments).
* Returns: int - Legacy return value: 1 = success; 0 = error.
*****************************************************************************/
-int do_cpld(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
+int do_cpld(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
int iErrorCode;
char* pzXsvfFileName;