From 4946096d43d1d02fb07cc80f82e1747b01571c41 Mon Sep 17 00:00:00 2001 From: Johan Hedberg Date: Tue, 8 Oct 2013 13:55:46 +0200 Subject: Bluetooth: Fix validating LE PSM values 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 Signed-off-by: Marcel Holtmann --- net/bluetooth/l2cap_sock.c | 40 +++++++++++++++++++++++++++++++--------- 1 file changed, 31 insertions(+), 9 deletions(-) (limited to 'net/bluetooth/l2cap_sock.c') diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c index a51844a8c5eb..88fa9c07c503 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) -- cgit v1.2.3