diff options
author | Wolfgang Denk <wd@denx.de> | 2010-06-28 20:00:46 (GMT) |
---|---|---|
committer | Wolfgang Denk <wd@denx.de> | 2010-07-04 21:55:42 (GMT) |
commit | 54841ab50c20d6fa6c9cc3eb826989da3a22d934 (patch) | |
tree | 400f22f0a12ff0ae6c472bed6ac648befc1744a2 /arch/blackfin | |
parent | b218ccb5435e64ac2318bb8b6c9594ef1cc724cd (diff) | |
download | u-boot-54841ab50c20d6fa6c9cc3eb826989da3a22d934.tar.xz |
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/blackfin')
-rw-r--r-- | arch/blackfin/cpu/bootrom-asm-offsets.c.in | 2 | ||||
-rw-r--r-- | arch/blackfin/cpu/reset.c | 2 | ||||
-rw-r--r-- | arch/blackfin/lib/boot.c | 2 | ||||
-rw-r--r-- | arch/blackfin/lib/cmd_cache_dump.c | 4 | ||||
-rw-r--r-- | arch/blackfin/lib/kgdb.c | 2 |
5 files changed, 6 insertions, 6 deletions
diff --git a/arch/blackfin/cpu/bootrom-asm-offsets.c.in b/arch/blackfin/cpu/bootrom-asm-offsets.c.in index 3146e46..64c2f24 100644 --- a/arch/blackfin/cpu/bootrom-asm-offsets.c.in +++ b/arch/blackfin/cpu/bootrom-asm-offsets.c.in @@ -9,4 +9,4 @@ #define _DEFINE(sym, val) asm volatile("\n->" #sym " %0 " #val : : "i" (val)) #define DEFINE(s, m) _DEFINE(offset_##s##_##m, offsetof(s, m)) -int main(int argc, char *argv[]) +int main(int argc, char * const argv[]) diff --git a/arch/blackfin/cpu/reset.c b/arch/blackfin/cpu/reset.c index e3be740..164afde 100644 --- a/arch/blackfin/cpu/reset.c +++ b/arch/blackfin/cpu/reset.c @@ -99,7 +99,7 @@ void bfin_reset_or_hang(void) #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[]) { bfin_reset_trampoline(); return 0; diff --git a/arch/blackfin/lib/boot.c b/arch/blackfin/lib/boot.c index 951d5b0..37aa82a 100644 --- a/arch/blackfin/lib/boot.c +++ b/arch/blackfin/lib/boot.c @@ -33,7 +33,7 @@ static char *make_command_line(void) extern ulong bfin_poweron_retx; -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) { int (*appl) (char *cmdline); char *cmdline; diff --git a/arch/blackfin/lib/cmd_cache_dump.c b/arch/blackfin/lib/cmd_cache_dump.c index de5840e..412e019 100644 --- a/arch/blackfin/lib/cmd_cache_dump.c +++ b/arch/blackfin/lib/cmd_cache_dump.c @@ -25,7 +25,7 @@ static int check_limit(const char *type, size_t start_limit, size_t end_limit, s return 1; } -int do_icache_dump(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) +int do_icache_dump(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) { int cache_status = icache_status(); @@ -97,7 +97,7 @@ U_BOOT_CMD(icache_dump, 4, 0, do_icache_dump, "icache_dump - dump current instruction cache\n", "[way] [subbank] [set]"); -int do_dcache_dump(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) +int do_dcache_dump(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) { u32 way, bank, subbank, set; u32 status, addr; diff --git a/arch/blackfin/lib/kgdb.c b/arch/blackfin/lib/kgdb.c index bd62d71..4ca3fc7 100644 --- a/arch/blackfin/lib/kgdb.c +++ b/arch/blackfin/lib/kgdb.c @@ -417,7 +417,7 @@ void kgdb_putregs(struct pt_regs *regs, char *buf, int length) } -void kgdb_breakpoint(int argc, char *argv[]) +void kgdb_breakpoint(int argc, char * const argv[]) { asm volatile ("excpt 0x1\n"); } |