diff options
author | Wolfgang Denk <wd@denx.de> | 2010-06-28 22:00:46 +0200 |
---|---|---|
committer | Wolfgang Denk <wd@denx.de> | 2010-07-04 23:55:42 +0200 |
commit | 54841ab50c20d6fa6c9cc3eb826989da3a22d934 (patch) | |
tree | 400f22f0a12ff0ae6c472bed6ac648befc1744a2 /arch/i386 | |
parent | b218ccb5435e64ac2318bb8b6c9594ef1cc724cd (diff) |
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>
Diffstat (limited to 'arch/i386')
-rw-r--r-- | arch/i386/cpu/cpu.c | 2 | ||||
-rw-r--r-- | arch/i386/lib/board.c | 2 | ||||
-rw-r--r-- | arch/i386/lib/bootm.c | 2 | ||||
-rw-r--r-- | arch/i386/lib/interrupts.c | 2 | ||||
-rw-r--r-- | arch/i386/lib/zimage.c | 2 |
5 files changed, 5 insertions, 5 deletions
diff --git a/arch/i386/cpu/cpu.c b/arch/i386/cpu/cpu.c index 3010519e74..bd6aced873 100644 --- a/arch/i386/cpu/cpu.c +++ b/arch/i386/cpu/cpu.c @@ -56,7 +56,7 @@ int cpu_init_r(void) return 0; } -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[]) { printf ("resetting ...\n"); udelay(50000); /* wait 50 ms */ diff --git a/arch/i386/lib/board.c b/arch/i386/lib/board.c index 3f849f6542..0adc66455a 100644 --- a/arch/i386/lib/board.c +++ b/arch/i386/lib/board.c @@ -431,7 +431,7 @@ void hang (void) for (;;); } -unsigned long do_go_exec (ulong (*entry)(int, char *[]), int argc, char *argv[]) +unsigned long do_go_exec (ulong (*entry)(int, char *[]), int argc, char * const argv[]) { /* * x86 does not use a dedicated register to pass the pointer diff --git a/arch/i386/lib/bootm.c b/arch/i386/lib/bootm.c index f96d7bd6da..b36e58d9ec 100644 --- a/arch/i386/lib/bootm.c +++ b/arch/i386/lib/bootm.c @@ -29,7 +29,7 @@ #include <asm/zimage.h> /*cmd_boot.c*/ -int do_bootm_linux(int flag, int argc, char *argv[], bootm_headers_t *images) +int do_bootm_linux(int flag, int argc, char * const argv[], bootm_headers_t *images) { void *base_ptr; ulong os_data, os_len; diff --git a/arch/i386/lib/interrupts.c b/arch/i386/lib/interrupts.c index 51def59954..5a28278280 100644 --- a/arch/i386/lib/interrupts.c +++ b/arch/i386/lib/interrupts.c @@ -136,7 +136,7 @@ void do_irq(int hw_irq) } #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 irq; diff --git a/arch/i386/lib/zimage.c b/arch/i386/lib/zimage.c index b39615a3e2..89fe015e6e 100644 --- a/arch/i386/lib/zimage.c +++ b/arch/i386/lib/zimage.c @@ -245,7 +245,7 @@ void boot_zimage(void *setup_base) enter_realmode(((u32)setup_base+SETUP_START_OFFSET)>>4, 0, ®s, ®s); } -int do_zboot (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) +int do_zboot (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) { void *base_ptr; void *bzImage_addr; |