From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-yw0-f182.google.com ([209.85.211.182]:55154 "EHLO mail-yw0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756078AbZLWOrD (ORCPT ); Wed, 23 Dec 2009 09:47:03 -0500 Date: Wed, 23 Dec 2009 16:46:05 +0200 From: Dan Carpenter To: Johannes Berg Cc: "John W. Linville" , "David S. Miller" , linux-wireless@vger.kernel.org, netdev@vger.kernel.org Subject: Re: [PATCH] cfg80211: fix error path in cfg80211_wext_siwscan Message-ID: <20091223144605.GA23721@bicker> References: <20091223132937.GG17923@bicker> <1261578815.7304.7.camel@johannes.local> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1261578815.7304.7.camel@johannes.local> Sender: linux-wireless-owner@vger.kernel.org List-ID: On Wed, Dec 23, 2009 at 03:33:35PM +0100, Johannes Berg wrote: > If there's an invalid channel or SSID, the code leaks > the scan request. Always free the scan request, unless > it was successfully given to the driver. > > Reported-by: Dan Carpenter > Signed-off-by: Johannes Berg > --- > I kinda prefer this, thoughts? > Looks good. Acked-by: Dan Carpenter regards, dan carpenter > net/wireless/scan.c | 13 +++++++++---- > 1 file changed, 9 insertions(+), 4 deletions(-) > > --- wireless-testing.orig/net/wireless/scan.c 2009-12-23 15:27:20.000000000 +0100 > +++ wireless-testing/net/wireless/scan.c 2009-12-23 15:32:52.000000000 +0100 > @@ -601,7 +601,7 @@ int cfg80211_wext_siwscan(struct net_dev > struct cfg80211_registered_device *rdev; > struct wiphy *wiphy; > struct iw_scan_req *wreq = NULL; > - struct cfg80211_scan_request *creq; > + struct cfg80211_scan_request *creq = NULL; > int i, err, n_channels = 0; > enum ieee80211_band band; > > @@ -694,8 +694,10 @@ int cfg80211_wext_siwscan(struct net_dev > /* translate "Scan for SSID" request */ > if (wreq) { > if (wrqu->data.flags & IW_SCAN_THIS_ESSID) { > - if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) > - return -EINVAL; > + if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) { > + err = -EINVAL; > + goto out; > + } > memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len); > creq->ssids[0].ssid_len = wreq->essid_len; > } > @@ -707,12 +709,15 @@ int cfg80211_wext_siwscan(struct net_dev > err = rdev->ops->scan(wiphy, dev, creq); > if (err) { > rdev->scan_req = NULL; > - kfree(creq); > + /* creq will be freed below */ > } else { > nl80211_send_scan_start(rdev, dev); > + /* creq now owned by driver */ > + creq = NULL; > dev_hold(dev); > } > out: > + kfree(creq); > cfg80211_unlock_rdev(rdev); > return err; > } >