From 4f3e219d95a3c31b916dcd5e2631c4e440736f79 Mon Sep 17 00:00:00 2001 From: Marcel Holtmann Date: Thu, 3 Oct 2013 01:26:37 -0700 Subject: [PATCH] Bluetooth: Only one command per L2CAP LE signalling is supported The Bluetooth specification makes it clear that only one command should be present in the L2CAP LE signalling packet. So tighten the checks here and restrict it to exactly one command. This is different from L2CAP BR/EDR signalling where multiple commands can be part of the same packet. Signed-off-by: Marcel Holtmann Signed-off-by: Johan Hedberg --- net/bluetooth/l2cap_core.c | 44 ++++++++++++++++---------------------- 1 file changed, 19 insertions(+), 25 deletions(-) diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index 583517e1dd43..02dba4e6df96 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -5322,43 +5322,37 @@ static inline void l2cap_le_sig_channel(struct l2cap_conn *conn, struct sk_buff *skb) { struct hci_conn *hcon = conn->hcon; - u8 *data = skb->data; - int len = skb->len; - struct l2cap_cmd_hdr cmd; + struct l2cap_cmd_hdr *cmd; + u16 len; int err; if (hcon->type != LE_LINK) goto drop; - while (len >= L2CAP_CMD_HDR_SIZE) { - u16 cmd_len; - memcpy(&cmd, data, L2CAP_CMD_HDR_SIZE); - data += L2CAP_CMD_HDR_SIZE; - len -= L2CAP_CMD_HDR_SIZE; + if (skb->len < L2CAP_CMD_HDR_SIZE) + goto drop; - cmd_len = le16_to_cpu(cmd.len); + cmd = (void *) skb->data; + skb_pull(skb, L2CAP_CMD_HDR_SIZE); - BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd.code, cmd_len, - cmd.ident); + len = le16_to_cpu(cmd->len); - if (cmd_len > len || !cmd.ident) { - BT_DBG("corrupted command"); - break; - } + BT_DBG("code 0x%2.2x len %d id 0x%2.2x", cmd->code, len, cmd->ident); - err = l2cap_le_sig_cmd(conn, &cmd, data); - if (err) { - struct l2cap_cmd_rej_unk rej; + if (len != skb->len || !cmd->ident) { + BT_DBG("corrupted command"); + goto drop; + } - BT_ERR("Wrong link type (%d)", err); + err = l2cap_le_sig_cmd(conn, cmd, skb->data); + if (err) { + struct l2cap_cmd_rej_unk rej; - rej.reason = l2cap_err_to_reason(err); - l2cap_send_cmd(conn, cmd.ident, L2CAP_COMMAND_REJ, - sizeof(rej), &rej); - } + BT_ERR("Wrong link type (%d)", err); - data += cmd_len; - len -= cmd_len; + rej.reason = l2cap_err_to_reason(err); + l2cap_send_cmd(conn, cmd->ident, L2CAP_COMMAND_REJ, + sizeof(rej), &rej); } drop: -- 2.20.1