[PATCH] wifi: libertas: fix WARNING in usb_tx_block

[Szymon Wilczek]

The function usb_tx_block() submits cardp->tx_urb without ensuring that
any previous transmission on this URB has completed. If a second call
occurs while the URB is still active (e.g. during rapid firmware loading),
usb_submit_urb() detects the active state and triggers a warning:
'URB submitted while active'.

Fix this by enforcing serialization: call usb_kill_urb() before
submitting the new request. This ensures the URB is idle and safe to reuse.

Reported-by: syzbot+67969ab6a2551c27f71b at syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=67969ab6a2551c27f71b
Signed-off-by: Szymon Wilczek <swilczek.lx at gmail.com>
---
 drivers/net/wireless/marvell/libertas/if_usb.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/wireless/marvell/libertas/if_usb.c b/drivers/net/wireless/marvell/libertas/if_usb.c
index b3c4040257a6..924ab93b7b67 100644
--- a/drivers/net/wireless/marvell/libertas/if_usb.c
+++ b/drivers/net/wireless/marvell/libertas/if_usb.c
@@ -426,6 +426,8 @@ static int usb_tx_block(struct if_usb_card *cardp, uint8_t *payload, uint16_t nb
 		goto tx_ret;
 	}
 
+	usb_kill_urb(cardp->tx_urb);
+
 	usb_fill_bulk_urb(cardp->tx_urb, cardp->udev,
 			  usb_sndbulkpipe(cardp->udev,
 					  cardp->ep_out),
-- 
2.52.0