From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:53698 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753728AbdJIHen (ORCPT ); Mon, 9 Oct 2017 03:34:43 -0400 Subject: Patch "net/sched: cls_matchall: fix crash when used with classful qdisc" has been added to the 4.13-stable tree To: dcaratti@redhat.com, davem@davemloft.net, gregkh@linuxfoundation.org, jbenc@redhat.com, yotamg@mellanox.com Cc: , From: Date: Mon, 09 Oct 2017 09:34:27 +0200 Message-ID: <1507534467139153@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled net/sched: cls_matchall: fix crash when used with classful qdisc to the 4.13-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-sched-cls_matchall-fix-crash-when-used-with-classful-qdisc.patch and it can be found in the queue-4.13 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From foo@baz Mon Oct 9 09:32:35 CEST 2017 From: Davide Caratti Date: Sat, 16 Sep 2017 14:02:21 +0200 Subject: net/sched: cls_matchall: fix crash when used with classful qdisc From: Davide Caratti [ Upstream commit 3ff4cbec87da48b0ec1f7b6196607b034de0c680 ] this script, edited from Linux Advanced Routing and Traffic Control guide tc q a dev en0 root handle 1: htb default a tc c a dev en0 parent 1: classid 1:1 htb rate 6mbit burst 15k tc c a dev en0 parent 1:1 classid 1:a htb rate 5mbit ceil 6mbit burst 15k tc c a dev en0 parent 1:1 classid 1:b htb rate 1mbit ceil 6mbit burst 15k tc f a dev en0 parent 1:0 prio 1 $clsname $clsargs classid 1:b ping $address -c1 tc -s c s dev en0 classifies traffic to 1:b or 1:a, depending on whether the packet matches or not the pattern $clsargs of filter $clsname. However, when $clsname is 'matchall', a systematic crash can be observed in htb_classify(). HTB and classful qdiscs don't assign initial value to struct tcf_result, but then they expect it to contain valid values after filters have been run. Thus, current 'matchall' ignores the TCA_MATCHALL_CLASSID attribute, configured by user, and makes HTB (and classful qdiscs) dereference random pointers. By assigning head->res to *res in mall_classify(), before the actions are invoked, we fix this crash and enable TCA_MATCHALL_CLASSID functionality, that had no effect on 'matchall' classifier since its first introduction. BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1460213 Reported-by: Jiri Benc Fixes: b87f7936a932 ("net/sched: introduce Match-all classifier") Signed-off-by: Davide Caratti Acked-by: Yotam Gigi Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/sched/cls_matchall.c | 1 + 1 file changed, 1 insertion(+) --- a/net/sched/cls_matchall.c +++ b/net/sched/cls_matchall.c @@ -32,6 +32,7 @@ static int mall_classify(struct sk_buff if (tc_skip_sw(head->flags)) return -1; + *res = head->res; return tcf_exts_exec(skb, &head->exts, res); } Patches currently in stable-queue which might be from dcaratti@redhat.com are queue-4.13/net-sched-cls_matchall-fix-crash-when-used-with-classful-qdisc.patch