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Diffstat (limited to 'net/bluetooth/l2cap_core.c')
-rw-r--r--net/bluetooth/l2cap_core.c136
1 files changed, 97 insertions, 39 deletions
diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index 1fc23cb4a3e0..11012a509070 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -1340,6 +1340,21 @@ static void l2cap_request_info(struct l2cap_conn *conn)
sizeof(req), &req);
}
+static bool l2cap_check_enc_key_size(struct hci_conn *hcon)
+{
+ /* The minimum encryption key size needs to be enforced by the
+ * host stack before establishing any L2CAP connections. The
+ * specification in theory allows a minimum of 1, but to align
+ * BR/EDR and LE transports, a minimum of 7 is chosen.
+ *
+ * This check might also be called for unencrypted connections
+ * that have no key size requirements. Ensure that the link is
+ * actually encrypted before enforcing a key size.
+ */
+ return (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags) ||
+ hcon->enc_key_size >= HCI_MIN_ENC_KEY_SIZE);
+}
+
static void l2cap_do_start(struct l2cap_chan *chan)
{
struct l2cap_conn *conn = chan->conn;
@@ -1357,9 +1372,14 @@ static void l2cap_do_start(struct l2cap_chan *chan)
if (!(conn->info_state & L2CAP_INFO_FEAT_MASK_REQ_DONE))
return;
- if (l2cap_chan_check_security(chan, true) &&
- __l2cap_no_conn_pending(chan))
+ if (!l2cap_chan_check_security(chan, true) ||
+ !__l2cap_no_conn_pending(chan))
+ return;
+
+ if (l2cap_check_enc_key_size(conn->hcon))
l2cap_start_connection(chan);
+ else
+ __set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
}
static inline int l2cap_mode_supported(__u8 mode, __u32 feat_mask)
@@ -1438,7 +1458,10 @@ static void l2cap_conn_start(struct l2cap_conn *conn)
continue;
}
- l2cap_start_connection(chan);
+ if (l2cap_check_enc_key_size(conn->hcon))
+ l2cap_start_connection(chan);
+ else
+ l2cap_chan_close(chan, ECONNREFUSED);
} else if (chan->state == BT_CONNECT2) {
struct l2cap_conn_rsp rsp;
@@ -3326,16 +3349,22 @@ static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data, size_t data
while (len >= L2CAP_CONF_OPT_SIZE) {
len -= l2cap_get_conf_opt(&req, &type, &olen, &val);
+ if (len < 0)
+ break;
hint = type & L2CAP_CONF_HINT;
type &= L2CAP_CONF_MASK;
switch (type) {
case L2CAP_CONF_MTU:
+ if (olen != 2)
+ break;
mtu = val;
break;
case L2CAP_CONF_FLUSH_TO:
+ if (olen != 2)
+ break;
chan->flush_to = val;
break;
@@ -3343,26 +3372,30 @@ static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data, size_t data
break;
case L2CAP_CONF_RFC:
- if (olen == sizeof(rfc))
- memcpy(&rfc, (void *) val, olen);
+ if (olen != sizeof(rfc))
+ break;
+ memcpy(&rfc, (void *) val, olen);
break;
case L2CAP_CONF_FCS:
+ if (olen != 1)
+ break;
if (val == L2CAP_FCS_NONE)
set_bit(CONF_RECV_NO_FCS, &chan->conf_state);
break;
case L2CAP_CONF_EFS:
- if (olen == sizeof(efs)) {
- remote_efs = 1;
- memcpy(&efs, (void *) val, olen);
- }
+ if (olen != sizeof(efs))
+ break;
+ remote_efs = 1;
+ memcpy(&efs, (void *) val, olen);
break;
case L2CAP_CONF_EWS:
+ if (olen != 2)
+ break;
if (!(chan->conn->local_fixed_chan & L2CAP_FC_A2MP))
return -ECONNREFUSED;
-
set_bit(FLAG_EXT_CTRL, &chan->flags);
set_bit(CONF_EWS_RECV, &chan->conf_state);
chan->tx_win_max = L2CAP_DEFAULT_EXT_WINDOW;
@@ -3372,7 +3405,6 @@ static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data, size_t data
default:
if (hint)
break;
-
result = L2CAP_CONF_UNKNOWN;
*((u8 *) ptr++) = type;
break;
@@ -3537,58 +3569,65 @@ static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len,
while (len >= L2CAP_CONF_OPT_SIZE) {
len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
+ if (len < 0)
+ break;
switch (type) {
case L2CAP_CONF_MTU:
+ if (olen != 2)
+ break;
if (val < L2CAP_DEFAULT_MIN_MTU) {
*result = L2CAP_CONF_UNACCEPT;
chan->imtu = L2CAP_DEFAULT_MIN_MTU;
} else
chan->imtu = val;
- l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu, endptr - ptr);
+ l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, chan->imtu,
+ endptr - ptr);
break;
case L2CAP_CONF_FLUSH_TO:
+ if (olen != 2)
+ break;
chan->flush_to = val;
- l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO,
- 2, chan->flush_to, endptr - ptr);
+ l2cap_add_conf_opt(&ptr, L2CAP_CONF_FLUSH_TO, 2,
+ chan->flush_to, endptr - ptr);
break;
case L2CAP_CONF_RFC:
- if (olen == sizeof(rfc))
- memcpy(&rfc, (void *)val, olen);
-
+ if (olen != sizeof(rfc))
+ break;
+ memcpy(&rfc, (void *)val, olen);
if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state) &&
rfc.mode != chan->mode)
return -ECONNREFUSED;
-
chan->fcs = 0;
-
- l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
- sizeof(rfc), (unsigned long) &rfc, endptr - ptr);
+ l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC, sizeof(rfc),
+ (unsigned long) &rfc, endptr - ptr);
break;
case L2CAP_CONF_EWS:
+ if (olen != 2)
+ break;
chan->ack_win = min_t(u16, val, chan->ack_win);
l2cap_add_conf_opt(&ptr, L2CAP_CONF_EWS, 2,
chan->tx_win, endptr - ptr);
break;
case L2CAP_CONF_EFS:
- if (olen == sizeof(efs)) {
- memcpy(&efs, (void *)val, olen);
-
- if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
- efs.stype != L2CAP_SERV_NOTRAFIC &&
- efs.stype != chan->local_stype)
- return -ECONNREFUSED;
-
- l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs),
- (unsigned long) &efs, endptr - ptr);
- }
+ if (olen != sizeof(efs))
+ break;
+ memcpy(&efs, (void *)val, olen);
+ if (chan->local_stype != L2CAP_SERV_NOTRAFIC &&
+ efs.stype != L2CAP_SERV_NOTRAFIC &&
+ efs.stype != chan->local_stype)
+ return -ECONNREFUSED;
+ l2cap_add_conf_opt(&ptr, L2CAP_CONF_EFS, sizeof(efs),
+ (unsigned long) &efs, endptr - ptr);
break;
case L2CAP_CONF_FCS:
+ if (olen != 1)
+ break;
if (*result == L2CAP_CONF_PENDING)
if (val == L2CAP_FCS_NONE)
set_bit(CONF_RECV_NO_FCS,
@@ -3717,13 +3756,18 @@ static void l2cap_conf_rfc_get(struct l2cap_chan *chan, void *rsp, int len)
while (len >= L2CAP_CONF_OPT_SIZE) {
len -= l2cap_get_conf_opt(&rsp, &type, &olen, &val);
+ if (len < 0)
+ break;
switch (type) {
case L2CAP_CONF_RFC:
- if (olen == sizeof(rfc))
- memcpy(&rfc, (void *)val, olen);
+ if (olen != sizeof(rfc))
+ break;
+ memcpy(&rfc, (void *)val, olen);
break;
case L2CAP_CONF_EWS:
+ if (olen != 2)
+ break;
txwin_ext = val;
break;
}
@@ -4330,6 +4374,12 @@ static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn,
l2cap_chan_lock(chan);
+ if (chan->state != BT_DISCONN) {
+ l2cap_chan_unlock(chan);
+ mutex_unlock(&conn->chan_lock);
+ return 0;
+ }
+
l2cap_chan_hold(chan);
l2cap_chan_del(chan, 0);
@@ -4858,10 +4908,8 @@ void __l2cap_physical_cfm(struct l2cap_chan *chan, int result)
BT_DBG("chan %p, result %d, local_amp_id %d, remote_amp_id %d",
chan, result, local_amp_id, remote_amp_id);
- if (chan->state == BT_DISCONN || chan->state == BT_CLOSED) {
- l2cap_chan_unlock(chan);
+ if (chan->state == BT_DISCONN || chan->state == BT_CLOSED)
return;
- }
if (chan->state != BT_CONNECTED) {
l2cap_do_create(chan, result, local_amp_id, remote_amp_id);
@@ -6761,6 +6809,16 @@ static int l2cap_le_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
chan->sdu_len = sdu_len;
chan->sdu_last_frag = skb;
+ /* Detect if remote is not able to use the selected MPS */
+ if (skb->len + L2CAP_SDULEN_SIZE < chan->mps) {
+ u16 mps_len = skb->len + L2CAP_SDULEN_SIZE;
+
+ /* Adjust the number of credits */
+ BT_DBG("chan->mps %u -> %u", chan->mps, mps_len);
+ chan->mps = mps_len;
+ l2cap_chan_le_send_credits(chan);
+ }
+
return 0;
}
@@ -7426,7 +7484,7 @@ static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
}
if (chan->state == BT_CONNECT) {
- if (!status)
+ if (!status && l2cap_check_enc_key_size(hcon))
l2cap_start_connection(chan);
else
__set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
@@ -7435,7 +7493,7 @@ static void l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
struct l2cap_conn_rsp rsp;
__u16 res, stat;
- if (!status) {
+ if (!status && l2cap_check_enc_key_size(hcon)) {
if (test_bit(FLAG_DEFER_SETUP, &chan->flags)) {
res = L2CAP_CR_PEND;
stat = L2CAP_CS_AUTHOR_PEND;
generated by cgit v1.2.3 (git 2.0.4) at 2024-05-01 14:03:17 +0000