On Mon, 2011-09-26 at 09:30 +0300, Dan Carpenter wrote: > wrqu->encoding.length comes from the network administrator. It's > size u16. We want to limit "tocopy" to the smallest value of either > "len_keys", "wrqu->encoding.length" or 100. But because .length > gets cast from u16 to u8 we might use a random, smaller value than > the was desired. It's probably not very serious, but we may as well > fix it. Nice catch. > Btw, this is from code auditing and not from testing. I don't know > if this affects anyone in real life. FWIW, it doesn't, the max key length that makes sense is 32 anyway, and since this is on an output path I doubt the min_t() will ever have done anything but returned "tocopy" :-) johannes > Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> > > diff --git a/drivers/net/wireless/wl3501_cs.c b/drivers/net/wireless/wl3501_cs.c > index 6bc7c92..98fbf54 100644 > --- a/drivers/net/wireless/wl3501_cs.c > +++ b/drivers/net/wireless/wl3501_cs.c > @@ -1781,7 +1781,7 @@ static int wl3501_get_encode(struct net_device *dev, > keys, len_keys); > if (rc) > goto out; > - tocopy = min_t(u8, len_keys, wrqu->encoding.length); > + tocopy = min_t(u16, len_keys, wrqu->encoding.length); > tocopy = min_t(u8, tocopy, 100); > wrqu->encoding.length = tocopy; > memcpy(extra, keys, tocopy); > -- > To unsubscribe from this list: send the line "unsubscribe linux-wireless" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
