This is a note to let you know that I've just added the patch titled
Bluetooth: L2CAP: Fix accepting connection request for invalid SPSM
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
bluetooth-l2cap-fix-accepting-connection-request-for-invalid-spsm.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>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: Bluetooth: L2CAP: Fix accepting connection request for invalid SPSM
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
From: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>
commit 711f8c3fb3db61897080468586b970c87c61d9e4 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/bluetooth/l2cap_core.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -5543,6 +5543,19 @@ static int l2cap_le_connect_req(struct l
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_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);
Patches currently in stable-queue which might be from luiz.von.dentz@xxxxxxxxx are
queue-4.9/bluetooth-l2cap-fix-accepting-connection-request-for-invalid-spsm.patch
