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 /common/cmd_yaffs2.c | |
parent | b218ccb5435e64ac2318bb8b6c9594ef1cc724cd (diff) | |
download | u-boot-imx-54841ab50c20d6fa6c9cc3eb826989da3a22d934.zip u-boot-imx-54841ab50c20d6fa6c9cc3eb826989da3a22d934.tar.gz u-boot-imx-54841ab50c20d6fa6c9cc3eb826989da3a22d934.tar.bz2 |
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 'common/cmd_yaffs2.c')
-rw-r--r-- | common/cmd_yaffs2.c | 24 |
1 files changed, 12 insertions, 12 deletions
diff --git a/common/cmd_yaffs2.c b/common/cmd_yaffs2.c index d448d04..7c01ea2 100644 --- a/common/cmd_yaffs2.c +++ b/common/cmd_yaffs2.c @@ -24,7 +24,7 @@ extern void cmd_yaffs_mv(const char *oldPath, const char *newPath); extern int yaffs_DumpDevStruct(const char *path); -int do_ymount (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) +int do_ymount (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) { char *mtpoint = argv[1]; cmd_yaffs_mount(mtpoint); @@ -32,7 +32,7 @@ int do_ymount (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) return(0); } -int do_yumount (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) +int do_yumount (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) { char *mtpoint = argv[1]; cmd_yaffs_umount(mtpoint); @@ -40,7 +40,7 @@ int do_yumount (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) return(0); } -int do_yls (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) +int do_yls (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) { char *dirname = argv[argc-1]; @@ -49,7 +49,7 @@ int do_yls (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) return(0); } -int do_yrd (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) +int do_yrd (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) { char *filename = argv[1]; printf ("Reading file %s ", filename); @@ -60,7 +60,7 @@ int do_yrd (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) return(0); } -int do_ywr (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) +int do_ywr (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) { char *filename = argv[1]; ulong value = simple_strtoul(argv[2], NULL, 16); @@ -74,7 +74,7 @@ int do_ywr (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) return(0); } -int do_yrdm (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) +int do_yrdm (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) { char *filename = argv[1]; ulong addr = simple_strtoul(argv[2], NULL, 16); @@ -84,7 +84,7 @@ int do_yrdm (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) return(0); } -int do_ywrm (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) +int do_ywrm (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) { char *filename = argv[1]; ulong addr = simple_strtoul(argv[2], NULL, 16); @@ -95,7 +95,7 @@ int do_ywrm (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) return(0); } -int do_ymkdir (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) +int do_ymkdir (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) { char *dirname = argv[1]; @@ -104,7 +104,7 @@ int do_ymkdir (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) return(0); } -int do_yrmdir (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) +int do_yrmdir (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) { char *dirname = argv[1]; @@ -113,7 +113,7 @@ int do_yrmdir (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) return(0); } -int do_yrm (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) +int do_yrm (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) { char *path = argv[1]; @@ -122,7 +122,7 @@ int do_yrm (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) return(0); } -int do_ymv (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) +int do_ymv (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) { char *oldPath = argv[1]; char *newPath = argv[2]; @@ -132,7 +132,7 @@ int do_ymv (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) return(0); } -int do_ydump (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) +int do_ydump (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) { char *dirname = argv[1]; if (yaffs_DumpDevStruct(dirname) != 0) |