usb: gadget: fix eem_wrap cloned skb logic

Even if the skb is cloned, we still need a ZLP or USB will stall.

Signed-off-by: Nathan Sullivan <nathan.sullivan@ni.com>
Acked-by: Brad Mouring <brad.mouring@ni.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 10 insertions, 12 deletions

diff --git a/drivers/usb/gadget/f_eem.c b/drivers/usb/gadget/f_eem.c
index d61c11d765d0..4d8b236ea608 100644
--- a/drivers/usb/gadget/f_eem.c
+++ b/drivers/usb/gadget/f_eem.c
@@ -355,20 +355,18 @@ static struct sk_buff *eem_wrap(struct gether *port, struct sk_buff *skb)
         int             padlen = 0;
         u16             len = skb->len;
 
-        if (!skb_cloned(skb)) {
-                int headroom = skb_headroom(skb);
-                int tailroom = skb_tailroom(skb);
+        int headroom = skb_headroom(skb);
+        int tailroom = skb_tailroom(skb);
 
-                /* When (len + EEM_HLEN + ETH_FCS_LEN) % in->maxpacket) is 0,
-                 * stick two bytes of zero-length EEM packet on the end.
-                 */
-                if (((len + EEM_HLEN + ETH_FCS_LEN) % in->maxpacket) == 0)
-                        padlen += 2;
+        /* When (len + EEM_HLEN + ETH_FCS_LEN) % in->maxpacket) is 0,
+         * stick two bytes of zero-length EEM packet on the end.
+         */
+        if (((len + EEM_HLEN + ETH_FCS_LEN) % in->maxpacket) == 0)
+                padlen += 2;
 
-                if ((tailroom >= (ETH_FCS_LEN + padlen)) &&
-                                (headroom >= EEM_HLEN))
-                        goto done;
-        }
+        if ((tailroom >= (ETH_FCS_LEN + padlen)) &&
+                        (headroom >= EEM_HLEN) && !skb_cloned(skb))
+                goto done;
 
         skb2 = skb_copy_expand(skb, EEM_HLEN, ETH_FCS_LEN + padlen, GFP_ATOMIC);
         dev_kfree_skb_any(skb);