Bluetooth: virtio_bt: Use skb_put to set length

[ Upstream commit 160fbcf3bfb93c3c086427f9f4c8bc70f217e9be ]

By using skb_put we ensure that skb->tail is set
correctly. Currently, skb->tail is always zero, which
leads to errors, such as the following page fault in
rfcomm_recv_frame:

    BUG: unable to handle page fault for address: ffffed1021de29ff
    #PF: supervisor read access in kernel mode
    #PF: error_code(0x0000) - not-present page
    RIP: 0010:rfcomm_run+0x831/0x4040 (net/bluetooth/rfcomm/core.c:1751)

Fixes: afd2daa26c7a ("Bluetooth: Add support for virtio transport driver")
Signed-off-by: Soenke Huster <soenke.huster@eknoes.de>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/bluetooth/virtio_bt.c b/drivers/bluetooth/virtio_bt.c
index 076e494..612f104 100644 (file)
--- a/drivers/bluetooth/virtio_bt.c
+++ b/drivers/bluetooth/virtio_bt.c
@@ -219,7 +219,7 @@ static void virtbt_rx_work(struct work_struct *work)
        if (!skb)
                return;
 
-       skb->len = len;
+       skb_put(skb, len);
        virtbt_rx_handle(vbt, skb);
 
        if (virtbt_add_inbuf(vbt) < 0)