FAILED: patch "[PATCH] Bluetooth: L2CAP: Fix accepting connection request for" failed to apply to 4.9-stable tree

[<gregkh@xxxxxxxxxxxxxxxxxxx>]

The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.

Possible dependencies:

711f8c3fb3db ("Bluetooth: L2CAP: Fix accepting connection request for invalid SPSM")
15f02b910562 ("Bluetooth: L2CAP: Add initial code for Enhanced Credit Based Mode")
571f739083e2 ("Bluetooth: Use separate L2CAP LE credit based connection result values")
96cd8eaa131f ("Bluetooth: L2CAP: Derive rx credits from MTU and MPS")
fe1493101ac1 ("Bluetooth: L2CAP: Derive MPS from connection MTU")
d8edd9ed156a ("Bluetooth: L2CAP: Fix L2CAP_CR_SCID_IN_USE value")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

>From 711f8c3fb3db61897080468586b970c87c61d9e4 Mon Sep 17 00:00:00 2001
From: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>
Date: Mon, 31 Oct 2022 16:10:32 -0700
Subject: [PATCH] Bluetooth: L2CAP: Fix accepting connection request for
 invalid SPSM
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The Bluetooth spec states that the valid range for SPSM is from
0x0001-0x00ff so it is invalid to accept values outside of this range:

  BLUETOOTH CORE SPECIFICATION Version 5.3 | Vol 3, Part A
  page 1059:
  Table 4.15: L2CAP_LE_CREDIT_BASED_CONNECTION_REQ SPSM ranges

CVE: CVE-2022-42896
CC: stable@xxxxxxxxxxxxxxx
Reported-by: Tamás Koczka <poprdi@xxxxxxxxxx>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>
Reviewed-by: Tedd Ho-Jeong An <tedd.an@xxxxxxxxx>

diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index 1fbe087d6ae4..3eee915fb245 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -5813,6 +5813,19 @@ static int l2cap_le_connect_req(struct l2cap_conn *conn,
 	BT_DBG("psm 0x%2.2x scid 0x%4.4x mtu %u mps %u", __le16_to_cpu(psm),
 	       scid, mtu, mps);
 
+	/* BLUETOOTH CORE SPECIFICATION Version 5.3 | Vol 3, Part A
+	 * page 1059:
+	 *
+	 * Valid range: 0x0001-0x00ff
+	 *
+	 * Table 4.15: L2CAP_LE_CREDIT_BASED_CONNECTION_REQ SPSM ranges
+	 */
+	if (!psm || __le16_to_cpu(psm) > L2CAP_PSM_LE_DYN_END) {
+		result = L2CAP_CR_LE_BAD_PSM;
+		chan = NULL;
+		goto response;
+	}
+
 	/* Check if we have socket listening on psm */
 	pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
 					 &conn->hcon->dst, LE_LINK);
@@ -6001,6 +6014,18 @@ static inline int l2cap_ecred_conn_req(struct l2cap_conn *conn,
 
 	psm  = req->psm;
 
+	/* BLUETOOTH CORE SPECIFICATION Version 5.3 | Vol 3, Part A
+	 * page 1059:
+	 *
+	 * Valid range: 0x0001-0x00ff
+	 *
+	 * Table 4.15: L2CAP_LE_CREDIT_BASED_CONNECTION_REQ SPSM ranges
+	 */
+	if (!psm || __le16_to_cpu(psm) > L2CAP_PSM_LE_DYN_END) {
+		result = L2CAP_CR_LE_BAD_PSM;
+		goto response;
+	}
+
 	BT_DBG("psm 0x%2.2x mtu %u mps %u", __le16_to_cpu(psm), mtu, mps);
 
 	memset(&pdu, 0, sizeof(pdu));