orinoco_usb: clean up some signedness issues

In ezusb_read_ltv() we had a comparison "(bufsize < 0)" which was never
true because bufsize was unsigned.  I looked at the implications of
that.  If we passed a negative number to ezusb_access_ltv() then it
would be used as the size parameter of the memcpy() because that
function uses min_t(int, exp_len, ans_size).

But fortunately when I looked at the callers, bufsize is not controlled
by the user and it's never negative.  So these signedness mistakes have
no impact.

I removed the always false check from ezusb_read_ltv() and I changed the
types in ezusb_access_ltv() and made the variables unsigned.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/net/wireless/orinoco/orinoco_usb.c b/drivers/net/wireless/orinoco/orinoco_usb.c
index 7f53cea2f2052ab8b4f23b53d08c2c8eca35ee20..01624dcaf73ed7f2d77b90b46eb342c5f2576816 100644 (file)
--- a/drivers/net/wireless/orinoco/orinoco_usb.c
+++ b/drivers/net/wireless/orinoco/orinoco_usb.c
@@ -865,7 +865,7 @@ static int ezusb_firmware_download(struct ezusb_priv *upriv,
 static int ezusb_access_ltv(struct ezusb_priv *upriv,
                            struct request_context *ctx,
                            u16 length, const void *data, u16 frame_type,
-                           void *ans_buff, int ans_size, u16 *ans_length)
+                           void *ans_buff, unsigned ans_size, u16 *ans_length)
 {
        int req_size;
        int retval = 0;
@@ -933,7 +933,7 @@ static int ezusb_access_ltv(struct ezusb_priv *upriv,
        }
        if (ctx->in_rid) {
                struct ezusb_packet *ans = ctx->buf;
-               int exp_len;
+               unsigned exp_len;
 
                if (ans->hermes_len != 0)
                        exp_len = le16_to_cpu(ans->hermes_len) * 2 + 12;
@@ -949,8 +949,7 @@ static int ezusb_access_ltv(struct ezusb_priv *upriv,
                }
 
                if (ans_buff)
-                       memcpy(ans_buff, ans->data,
-                              min_t(int, exp_len, ans_size));
+                       memcpy(ans_buff, ans->data, min(exp_len, ans_size));
                if (ans_length)
                        *ans_length = le16_to_cpu(ans->hermes_len);
        }
@@ -995,7 +994,7 @@ static int ezusb_read_ltv(struct hermes *hw, int bap, u16 rid,
        struct ezusb_priv *upriv = hw->priv;
        struct request_context *ctx;
 
-       if ((bufsize < 0) || (bufsize % 2))
+       if (bufsize % 2)
                return -EINVAL;
 
        ctx = ezusb_alloc_ctx(upriv, rid, rid);