From 3e8a7573ff9f43b76e7056b5ed32ea4b93e6ca10 Mon Sep 17 00:00:00 2001 From: Sungwoo Kim Date: Sat, 3 Jun 2023 08:28:09 -0400 Subject: [PATCH] Bluetooth: L2CAP: Add missing checks for invalid DCID [ Upstream commit 75767213f3d9b97f63694d02260b6a49a2271876 ] When receiving a connect response we should make sure that the DCID is within the valid range and that we don't already have another channel allocated for the same DCID. Missing checks may violate the specification (BLUETOOTH CORE SPECIFICATION Version 5.4 | Vol 3, Part A, Page 1046). Fixes: 40624183c202 ("Bluetooth: L2CAP: Add missing checks for invalid LE DCID") Signed-off-by: Sungwoo Kim Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin --- net/bluetooth/l2cap_core.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index 1287de3..02fc9961 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -4307,6 +4307,10 @@ static int l2cap_connect_create_rsp(struct l2cap_conn *conn, result = __le16_to_cpu(rsp->result); status = __le16_to_cpu(rsp->status); + if (result == L2CAP_CR_SUCCESS && (dcid < L2CAP_CID_DYN_START || + dcid > L2CAP_CID_DYN_END)) + return -EPROTO; + BT_DBG("dcid 0x%4.4x scid 0x%4.4x result 0x%2.2x status 0x%2.2x", dcid, scid, result, status); @@ -4338,6 +4342,11 @@ static int l2cap_connect_create_rsp(struct l2cap_conn *conn, switch (result) { case L2CAP_CR_SUCCESS: + if (__l2cap_get_chan_by_dcid(conn, dcid)) { + err = -EBADSLT; + break; + } + l2cap_state_change(chan, BT_CONFIG); chan->ident = 0; chan->dcid = dcid; -- 2.7.4