Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758982Ab2FQS1o (ORCPT ); Sun, 17 Jun 2012 14:27:44 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:50363 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758508Ab2FQSW5 (ORCPT ); Sun, 17 Jun 2012 14:22:57 -0400 Message-Id: <20120617175945.852510901@decadent.org.uk> User-Agent: quilt/0.60-1 Date: Sun, 17 Jun 2012 19:00:13 +0100 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Johannes Berg , Mohammed Shafi Shajakhan , "John W. Linville" Subject: [ 32/69] cfg80211: fix interface combinations check In-Reply-To: <20120617175941.281333656@decadent.org.uk> X-SA-Exim-Connect-IP: 2001:470:1f08:1539:21c:bfff:fe03:f805 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2916 Lines: 87 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johannes Berg commit 463454b5dbd8dbab6e2fc6c557329e5b811b9c32 upstream. If a given interface combination doesn't contain a required interface type then we missed checking that and erroneously allowed it even though iface type wasn't there at all. Add a check that makes sure that all interface types are accounted for. Reported-by: Mohammed Shafi Shajakhan Signed-off-by: Johannes Berg Signed-off-by: John W. Linville Signed-off-by: Ben Hutchings --- net/wireless/util.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) diff --git a/net/wireless/util.c b/net/wireless/util.c index 55d9946..8f2d68f 100644 --- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -935,6 +935,7 @@ int cfg80211_can_change_interface(struct cfg80211_registered_device *rdev, enum nl80211_iftype iftype) { struct wireless_dev *wdev_iter; + u32 used_iftypes = BIT(iftype); int num[NUM_NL80211_IFTYPES]; int total = 1; int i, j; @@ -961,6 +962,7 @@ int cfg80211_can_change_interface(struct cfg80211_registered_device *rdev, num[wdev_iter->iftype]++; total++; + used_iftypes |= BIT(wdev_iter->iftype); } mutex_unlock(&rdev->devlist_mtx); @@ -970,6 +972,7 @@ int cfg80211_can_change_interface(struct cfg80211_registered_device *rdev, for (i = 0; i < rdev->wiphy.n_iface_combinations; i++) { const struct ieee80211_iface_combination *c; struct ieee80211_iface_limit *limits; + u32 all_iftypes = 0; c = &rdev->wiphy.iface_combinations[i]; @@ -984,6 +987,7 @@ int cfg80211_can_change_interface(struct cfg80211_registered_device *rdev, if (rdev->wiphy.software_iftypes & BIT(iftype)) continue; for (j = 0; j < c->n_limits; j++) { + all_iftypes |= limits[j].types; if (!(limits[j].types & BIT(iftype))) continue; if (limits[j].max < num[iftype]) @@ -991,7 +995,20 @@ int cfg80211_can_change_interface(struct cfg80211_registered_device *rdev, limits[j].max -= num[iftype]; } } - /* yay, it fits */ + + /* + * Finally check that all iftypes that we're currently + * using are actually part of this combination. If they + * aren't then we can't use this combination and have + * to continue to the next. + */ + if ((all_iftypes & used_iftypes) != used_iftypes) + goto cont; + + /* + * This combination covered all interface types and + * supported the requested numbers, so we're good. + */ kfree(limits); return 0; cont: -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/