From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg Kroah-Hartman Subject: [PATCH 2/2] Bluetooth: check the buffer size for some messages before parsing Date: Thu, 10 Jan 2019 07:29:17 +0100 Message-ID: <20190110062917.GB15047@kroah.com> References: <20190110062833.GA15047@kroah.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-bluetooth@vger.kernel.org, netdev@vger.kernel.org, Ran Menscher To: Marcel Holtmann , Johan Hedberg Return-path: Received: from mail.kernel.org ([198.145.29.99]:37866 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726968AbfAJG3U (ORCPT ); Thu, 10 Jan 2019 01:29:20 -0500 Content-Disposition: inline In-Reply-To: <20190110062833.GA15047@kroah.com> Sender: netdev-owner@vger.kernel.org List-ID: The L2CAP_CONF_EFS and L2CAP_CONF_RFC messages can be sent from userspace so their structure sizes need to be checked before parsing them. Based on a patch from Ran Menscher. Reported-by: Ran Menscher Signed-off-by: Greg Kroah-Hartman --- net/bluetooth/l2cap_core.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c index 93daf94565cf..55e48e6efc2b 100644 --- a/net/bluetooth/l2cap_core.c +++ b/net/bluetooth/l2cap_core.c @@ -3361,7 +3361,8 @@ static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data, size_t data break; case L2CAP_CONF_RFC: - if (olen == sizeof(rfc)) + if ((olen == sizeof(rfc)) && + (endptr - ptr >= L2CAP_CONF_OPT_SIZE + sizeof(rfc))) memcpy(&rfc, (void *) val, olen); break; @@ -3371,7 +3372,8 @@ static int l2cap_parse_conf_req(struct l2cap_chan *chan, void *data, size_t data break; case L2CAP_CONF_EFS: - if (olen == sizeof(efs)) { + if ((olen == sizeof(efs)) && + (endptr - ptr >= L2CAP_CONF_OPT_SIZE + sizeof(efs))) { remote_efs = 1; memcpy(&efs, (void *) val, olen); } @@ -3576,7 +3578,8 @@ static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len, break; case L2CAP_CONF_RFC: - if (olen == sizeof(rfc)) + if ((olen == sizeof(rfc)) && + (endptr - ptr >= L2CAP_CONF_OPT_SIZE + sizeof(rfc))) memcpy(&rfc, (void *)val, olen); if (test_bit(CONF_STATE2_DEVICE, &chan->conf_state) && @@ -3596,7 +3599,8 @@ static int l2cap_parse_conf_rsp(struct l2cap_chan *chan, void *rsp, int len, break; case L2CAP_CONF_EFS: - if (olen == sizeof(efs)) { + if ((olen == sizeof(efs)) && + (endptr - ptr >= L2CAP_CONF_OPT_SIZE + sizeof(efs))) { memcpy(&efs, (void *)val, olen); if (chan->local_stype != L2CAP_SERV_NOTRAFIC && -- 2.20.1