Valid L2CAP PSMs are odd numbers, and the least significant bit of the most significant byte must be 0.
Signed-off-by: Mat Martineau <[email protected]> --- net/bluetooth/l2cap.c | 24 ++++++++++++++++++++---- 1 files changed, 20 insertions(+), 4 deletions(-) diff --git a/net/bluetooth/l2cap.c b/net/bluetooth/l2cap.c index c784703..1f1fa3c 100644 --- a/net/bluetooth/l2cap.c +++ b/net/bluetooth/l2cap.c @@ -1008,10 +1008,20 @@ static int l2cap_sock_bind(struct socket *sock, struct sockaddr *addr, int alen) goto done; } - if (la.l2_psm && __le16_to_cpu(la.l2_psm) < 0x1001 && - !capable(CAP_NET_BIND_SERVICE)) { - err = -EACCES; - goto done; + 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; + } + + /* Restrict usage of well-known PSMs */ + if (psm < 0x1001 && !capable(CAP_NET_BIND_SERVICE)) { + err = -EACCES; + goto done; + } } write_lock_bh(&l2cap_sk_list.lock); @@ -1190,6 +1200,12 @@ static int l2cap_sock_connect(struct socket *sock, struct sockaddr *addr, int al goto done; } + /* PSM must be odd and lsb of upper byte must be 0 */ + if ((__le16_to_cpu(la.l2_psm) & 0x0101) != 0x0001) { + err = -EINVAL; + goto done; + } + /* Set destination address and psm */ bacpy(&bt_sk(sk)->dst, &la.l2_bdaddr); l2cap_pi(sk)->psm = la.l2_psm; -- 1.7.1 -- Mat Martineau Employee of Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
