cm4000_cs: Use struct_group() to zero struct cm4000_dev region

In preparation for FORTIFY_SOURCE performing compile-time and run-time
field bounds checking for memset(), avoid intentionally writing across
neighboring fields.

Add struct_group() to mark region of struct cm4000_dev that should be
initialized to zero.

Cc: Harald Welte <laforge@gnumonks.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/lkml/YQDvxAofJlI1JoGZ@kroah.com
This commit is contained in:
Kees Cook 2021-05-20 15:33:30 -07:00
parent c92a08c1af
commit 8610047ca8

View file

@ -116,8 +116,9 @@ struct cm4000_dev {
wait_queue_head_t atrq; /* wait for ATR valid */
wait_queue_head_t readq; /* used by write to wake blk.read */
/* warning: do not move this fields.
/* warning: do not move this struct group.
* initialising to zero depends on it - see ZERO_DEV below. */
struct_group(init,
unsigned char atr_csum;
unsigned char atr_len_retry;
unsigned short atr_len;
@ -140,12 +141,10 @@ struct cm4000_dev {
struct timer_list timer; /* used to keep monitor running */
int monitor_running;
);
};
#define ZERO_DEV(dev) \
memset(&dev->atr_csum,0, \
sizeof(struct cm4000_dev) - \
offsetof(struct cm4000_dev, atr_csum))
#define ZERO_DEV(dev) memset(&((dev)->init), 0, sizeof((dev)->init))
static struct pcmcia_device *dev_table[CM4000_MAX_DEV];
static struct class *cmm_class;