From: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>
L2CAP_ECRED_CONN_RSP needs to respond DCID in the same order received as
SCID but the order is reversed due to use of list_add which actually
prepend channels to the list so the response is reversed:
> ACL Data RX: Handle 16 flags 0x02 dlen 26
LE L2CAP: Enhanced Credit Connection Request (0x17) ident 2 len 18
PSM: 39 (0x0027)
MTU: 256
MPS: 251
Credits: 65535
Source CID: 116
Source CID: 117
Source CID: 118
Source CID: 119
Source CID: 120
< ACL Data TX: Handle 16 flags 0x00 dlen 26
LE L2CAP: Enhanced Credit Connection Response (0x18) ident 2 len 18
MTU: 517
MPS: 247
Credits: 3
Result: Connection successful (0x0000)
Destination CID: 68
Destination CID: 67
Destination CID: 66
Destination CID: 65
Destination CID: 64
Closes: https://github.com/bluez/bluez/issues/1094
Fixes: 9aa9d9473f15 ("Bluetooth: L2CAP: Fix responding with wrong PDU type")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>
---
net/bluetooth/l2cap_core.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index fec11e576f31..2ffb8c35dbe2 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -632,7 +632,8 @@ void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
test_bit(FLAG_HOLD_HCI_CONN, &chan->flags))
hci_conn_hold(conn->hcon);
- list_add(&chan->list, &conn->chan_l);
+ /* Append to the list since the order matters for ECRED */
+ list_add_tail(&chan->list, &conn->chan_l);
}
void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
--
2.48.1
