From: Luiz Augusto von Dentz luiz.von.dentz@intel.com
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 Reported-by: Tamás Koczka poprdi@google.com Signed-off-by: Luiz Augusto von Dentz luiz.von.dentz@intel.com Reviewed-by: Tedd Ho-Jeong An tedd.an@intel.com Cc: stable@vger.kernel.org # 5.4.x Signed-off-by: Cengiz Can cengiz.can@canonical.com --- net/bluetooth/l2cap_core.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+)
diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index d4d818f3caa7..c4c25af1dbd5 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -5686,6 +5686,19 @@ 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); @@ -5864,6 +5877,18 @@ static inline int l2cap_ecred_conn_req(struct l2cap_conn *conn, psm = req->psm; credits = 0;
+ /* 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));