Bluetooth: SCO: Fix sco_send_frame returning skb->len

BugLink: https://bugs.launchpad.net/bugs/1988479
commit 037ce005af6b8a3e40ee07c6e9266c8997e6a4d6 upstream.

The skb in modified by hci_send_sco which pushes SCO headers thus
changing skb->len causing sco_sock_sendmsg to fail.

Fixes: 0771cbb3b97d ("Bluetooth: SCO: Replace use of memcpy_from_msg with bt_skb_sendmsg")
Tested-by: Tedd Ho-Jeong An <tedd.an@intel.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c
index 17ca65fb6c50d788ae63d0a2af80a649ec8b166d..9a8814d4565a0b07d57872d0f6f3d76104895933 100644 (file)
--- a/net/bluetooth/sco.c
+++ b/net/bluetooth/sco.c
@@ -283,16 +283,17 @@ static int sco_connect(struct hci_dev *hdev, struct sock *sk)
 static int sco_send_frame(struct sock *sk, struct sk_buff *skb)
 {
        struct sco_conn *conn = sco_pi(sk)->conn;
+       int len = skb->len;
 
        /* Check outgoing MTU */
-       if (skb->len > conn->mtu)
+       if (len > conn->mtu)
                return -EINVAL;
 
-       BT_DBG("sk %p len %d", sk, skb->len);
+       BT_DBG("sk %p len %d", sk, len);
 
        hci_send_sco(conn->hcon, skb);
 
-       return skb->len;
+       return len;
 }
 
 static void sco_recv_frame(struct sco_conn *conn, struct sk_buff *skb)
@@ -743,7 +744,8 @@ static int sco_sock_sendmsg(struct socket *sock, struct msghdr *msg,
                err = -ENOTCONN;
 
        release_sock(sk);
-       if (err)
+
+       if (err < 0)
                kfree_skb(skb);
        return err;
 }