Return-path: Received: from s3.sipsolutions.net ([5.9.151.49]:39098 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935282AbdAIKKq (ORCPT ); Mon, 9 Jan 2017 05:10:46 -0500 From: Johannes Berg To: linux-wireless@vger.kernel.org Cc: Johannes Berg Subject: [PATCH] cfg80211: size various nl80211 messages correctly Date: Mon, 9 Jan 2017 11:10:42 +0100 Message-Id: <20170109101042.23919-1-johannes@sipsolutions.net> (sfid-20170109_111110_076021_AF096544) Sender: linux-wireless-owner@vger.kernel.org List-ID: From: Johannes Berg Ilan reported that sometimes nl80211 messages weren't working if the frames being transported got very large, which was really a problem for userspace-to-kernel messages, but prompted me to look at the code. Upon review, I found various places where variable-length data is transported in an nl80211 message but the message isn't allocated taking that into account. This shouldn't cause any problems since the frames aren't really that long, apart in one place where two (possibly very long frames) might not fit. Fix all the places (that I found) that get variable length data from the driver and put it into a message to take the length of the variable data into account. The 100 there is just a safe constant for the remaining message overhead (it's usually around 50 for most messages.) Signed-off-by: Johannes Berg --- net/wireless/nl80211.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 23692658fe98..f55b251e4b0d 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -13249,7 +13249,7 @@ void nl80211_send_disconnected(struct cfg80211_registered_device *rdev, struct sk_buff *msg; void *hdr; - msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + msg = nlmsg_new(100 + ie_len, GFP_KERNEL); if (!msg) return; @@ -13325,7 +13325,7 @@ void cfg80211_notify_new_peer_candidate(struct net_device *dev, const u8 *addr, trace_cfg80211_notify_new_peer_candidate(dev, addr); - msg = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp); + msg = nlmsg_new(100 + ie_len, gfp); if (!msg) return; @@ -13362,7 +13362,7 @@ void nl80211_michael_mic_failure(struct cfg80211_registered_device *rdev, struct sk_buff *msg; void *hdr; - msg = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp); + msg = nlmsg_new(100 + req_ie_len + resp_ie_len, gfp); if (!msg) return; @@ -13456,7 +13456,7 @@ static void nl80211_send_remain_on_chan_event( struct sk_buff *msg; void *hdr; - msg = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp); + msg = nlmsg_new(100 + len, gfp); if (!msg) return; @@ -13696,7 +13696,7 @@ int nl80211_send_mgmt(struct cfg80211_registered_device *rdev, struct sk_buff *msg; void *hdr; - msg = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp); + msg = nlmsg_new(100 + len, gfp); if (!msg) return -ENOMEM; @@ -13740,7 +13740,7 @@ void cfg80211_mgmt_tx_status(struct wireless_dev *wdev, u64 cookie, trace_cfg80211_mgmt_tx_status(wdev, cookie, ack); - msg = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp); + msg = nlmsg_new(100 + len, gfp); if (!msg) return; @@ -14046,7 +14046,7 @@ static void nl80211_ch_switch_notify(struct cfg80211_registered_device *rdev, struct sk_buff *msg; void *hdr; - msg = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp); + msg = nlmsg_new(100 + req_ie_len + resp_ie_len, gfp); if (!msg) return; @@ -14551,7 +14551,7 @@ void cfg80211_ft_event(struct net_device *netdev, if (!ft_event->target_ap) return; - msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + msg = nlmsg_new(100 + ft_event->ric_ies_len, GFP_KERNEL); if (!msg) return; -- 2.9.3