If the string is invalid, this should return -EINVAL instead of 0.
Fixes: 73517cf49bd4 ("usb: gadget: add RNDIS configfs options for class/subclass/protocol")
Cc: stable <stable@vger.kernel.org>
Acked-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/YCqZ3P53yyIg5cn7@mwanda
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
                                                size_t len)             \
        {                                                               \
                struct f_##_f_##_opts *opts = to_f_##_f_##_opts(item);  \
-               int ret;                                                \
+               int ret = -EINVAL;                                      \
                u8 val;                                                 \
                                                                        \
                mutex_lock(&opts->lock);                                \
-               ret = sscanf(page, "%02hhx", &val);                     \
-               if (ret > 0) {                                          \
+               if (sscanf(page, "%02hhx", &val) > 0) {                 \
                        opts->_n_ = val;                                \
                        ret = len;                                      \
                }                                                       \