6.6-stable review patch. If anyone has any objections, please let me know.
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From: Luiz Augusto von Dentz luiz.von.dentz@intel.com
[ Upstream commit b25120e1d5f2ebb3db00af557709041f47f7f3d0 ]
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
Also make sure the response don't include channels that are not on BT_CONNECT2 since the chan->ident can be set to the same value as in the following trace:
< ACL Data TX: Handle 16 flags 0x00 dlen 12 LE L2CAP: LE Flow Control Credit (0x16) ident 6 len 4 Source CID: 64 Credits: 1 ...
ACL Data RX: Handle 16 flags 0x02 dlen 18
LE L2CAP: Enhanced Credit Connection Request (0x17) ident 6 len 10 PSM: 39 (0x0027) MTU: 517 MPS: 251 Credits: 255 Source CID: 70 < ACL Data TX: Handle 16 flags 0x00 dlen 20 LE L2CAP: Enhanced Credit Connection Response (0x18) ident 6 len 12 MTU: 517 MPS: 247 Credits: 3 Result: Connection successful (0x0000) Destination CID: 64 Destination CID: 68
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@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- net/bluetooth/l2cap_core.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index acb148759bd04..304ebb31cebba 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -636,7 +636,8 @@ 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) @@ -3774,7 +3775,11 @@ static void l2cap_ecred_rsp_defer(struct l2cap_chan *chan, void *data) { struct l2cap_ecred_rsp_data *rsp = data;
- if (test_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags)) + /* Check if channel for outgoing connection or if it wasn't deferred + * since in those cases it must be skipped. + */ + if (test_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags) || + !test_and_clear_bit(FLAG_DEFER_SETUP, &chan->flags)) return;
/* Reset ident so only one response is sent */