From: Johan Hedberg <johan.hedberg@xxxxxxxxx>
LE PSM values have different ranges than those for BR/EDR. The valid
ranges for fixed, SIG assigned values is 0x0001-0x007f and for dynamic
PSM values 0x0080-0x00ff. We need to ensure that bind() and connect()
calls conform to these ranges when operating on LE CoC sockets.
Signed-off-by: Johan Hedberg <johan.hedberg@xxxxxxxxx>
---
net/bluetooth/l2cap_core.c | 15 +++++++++++++--
net/bluetooth/l2cap_sock.c | 40 +++++++++++++++++++++++++++++++---------
2 files changed, 44 insertions(+), 11 deletions(-)
diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index e447bbedcabf..c638c280db40 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -1861,6 +1861,18 @@ static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm,
return c1;
}
+static bool is_valid_psm(u16 psm, u8 dst_type)
+{
+ if (!psm)
+ return false;
+
+ if (bdaddr_type_is_le(dst_type))
+ return (psm < 0x00ff);
+
+ /* PSM must be odd and lsb of upper byte must be 0 */
+ return ((psm & 0x0101) == 0x0001);
+}
+
int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
bdaddr_t *dst, u8 dst_type)
{
@@ -1881,8 +1893,7 @@ int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
l2cap_chan_lock(chan);
- /* PSM must be odd and lsb of upper byte must be 0 */
- if ((__le16_to_cpu(psm) & 0x0101) != 0x0001 && !cid &&
+ if (!is_valid_psm(__le16_to_cpu(psm), dst_type) && !cid &&
chan->chan_type != L2CAP_CHAN_RAW) {
err = -EINVAL;
goto done;
diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c
index c2424782c245..f4471fd6e99e 100644
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c
@@ -53,6 +53,32 @@ bool l2cap_is_socket(struct socket *sock)
}
EXPORT_SYMBOL(l2cap_is_socket);
+static int l2cap_validate_bredr_psm(u16 psm)
+{
+ /* PSM must be odd and lsb of upper byte must be 0 */
+ if ((psm & 0x0101) != 0x0001)
+ return -EINVAL;
+
+ /* Restrict usage of well-known PSMs */
+ if (psm < 0x1001 && !capable(CAP_NET_BIND_SERVICE))
+ return -EACCES;
+
+ return 0;
+}
+
+static int l2cap_validate_le_psm(u16 psm)
+{
+ /* Valid LE_PSM ranges are defined only until 0x00ff */
+ if (psm > 0x00ff)
+ return -EINVAL;
+
+ /* Restrict fixed, SIG assigned PSM values to CAP_NET_BIND_SERVICE */
+ if (psm <= 0x007f && !capable(CAP_NET_BIND_SERVICE))
+ return -EACCES;
+
+ return 0;
+}
+
static int l2cap_sock_bind(struct socket *sock, struct sockaddr *addr, int alen)
{
struct sock *sk = sock->sk;
@@ -94,17 +120,13 @@ static int l2cap_sock_bind(struct socket *sock, struct sockaddr *addr, int alen)
if (la.l2_psm) {
__u16 psm = __le16_to_cpu(la.l2_psm);
- /* PSM must be odd and lsb of upper byte must be 0 */
- if ((psm & 0x0101) != 0x0001) {
- err = -EINVAL;
- goto done;
- }
+ if (la.l2_bdaddr_type == BDADDR_BREDR)
+ err = l2cap_validate_bredr_psm(psm);
+ else
+ err = l2cap_validate_le_psm(psm);
- /* Restrict usage of well-known PSMs */
- if (psm < 0x1001 && !capable(CAP_NET_BIND_SERVICE)) {
- err = -EACCES;
+ if (err)
goto done;
- }
}
if (la.l2_cid)
--
1.8.4.2
--
To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
