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/arch/powerpc/cpu/ppc4xx/44x_spd_ddr2.c b/arch/powerpc/cpu/ppc4xx/44x_spd_ddr2.c
index b2cc2fe..ff5ef5f 100644
--- a/arch/powerpc/cpu/ppc4xx/44x_spd_ddr2.c
+++ b/arch/powerpc/cpu/ppc4xx/44x_spd_ddr2.c
@@ -418,7 +418,7 @@
static void DQS_calibration_process(void);
#endif
#endif
-int do_reset (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]);
+int do_reset (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]);
static unsigned char spd_read(uchar chip, uint addr)
{
diff --git a/arch/powerpc/cpu/ppc4xx/bedbug_405.c b/arch/powerpc/cpu/ppc4xx/bedbug_405.c
index ef11cb6..e1500cc 100644
--- a/arch/powerpc/cpu/ppc4xx/bedbug_405.c
+++ b/arch/powerpc/cpu/ppc4xx/bedbug_405.c
@@ -17,7 +17,7 @@
extern CPU_DEBUG_CTX bug_ctx;
void bedbug405_init __P ((void));
-void bedbug405_do_break __P ((cmd_tbl_t *, int, int, char *[]));
+void bedbug405_do_break __P ((cmd_tbl_t *, int, int, char * const []));
void bedbug405_break_isr __P ((struct pt_regs *));
int bedbug405_find_empty __P ((void));
int bedbug405_set __P ((int, unsigned long));
@@ -63,7 +63,7 @@
* set routine which will assign a breakpoint number.
* ====================================================================== */
-void bedbug405_do_break (cmd_tbl_t * cmdtp, int flag, int argc, char *argv[])
+void bedbug405_do_break (cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[])
{
long addr = 0; /* Address to break at */
int which_bp; /* Breakpoint number */
diff --git a/arch/powerpc/cpu/ppc4xx/cmd_chip_config.c b/arch/powerpc/cpu/ppc4xx/cmd_chip_config.c
index ba57211..72c5aec 100644
--- a/arch/powerpc/cpu/ppc4xx/cmd_chip_config.c
+++ b/arch/powerpc/cpu/ppc4xx/cmd_chip_config.c
@@ -45,7 +45,7 @@
}
-static int do_chip_config(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
+static int do_chip_config(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
int i;
int ret;
diff --git a/arch/powerpc/cpu/ppc4xx/cpu.c b/arch/powerpc/cpu/ppc4xx/cpu.c
index e1a023b..851065c 100644
--- a/arch/powerpc/cpu/ppc4xx/cpu.c
+++ b/arch/powerpc/cpu/ppc4xx/cpu.c
@@ -688,7 +688,7 @@
/* ------------------------------------------------------------------------- */
-int do_reset (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
+int do_reset (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
#if defined(CONFIG_BOARD_RESET)
board_reset();
diff --git a/arch/powerpc/cpu/ppc4xx/interrupts.c b/arch/powerpc/cpu/ppc4xx/interrupts.c
index 6db8421..c89bf37 100644
--- a/arch/powerpc/cpu/ppc4xx/interrupts.c
+++ b/arch/powerpc/cpu/ppc4xx/interrupts.c
@@ -194,7 +194,7 @@
}
#if defined(CONFIG_CMD_IRQ)
-int do_irqinfo(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
+int do_irqinfo(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
int vec;