From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id ACFCAC433EF for ; Sun, 8 Sep 2019 12:56:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 856D820693 for ; Sun, 8 Sep 2019 12:56:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567947385; bh=LP2tWWU6SNcc0eaVpBGE6cJjoSO6JWYhOXJUvaUUgV8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=BAHnZxYblgFpWj4qT5sz3EEjoV6yHHNQTHQOKwT6xM6u4eMajmsUYCbsz7EwADjYr fgA+1bKZReT/NMM90S/+0Nd9iZcasuZ1prOSA72YK2YMB2lopg/B98SLA3CoJue+5e cIS2qoW1by67RJkMLgBP0/T2fUc1DiracAhtd8sc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731646AbfIHMto (ORCPT ); Sun, 8 Sep 2019 08:49:44 -0400 Received: from mail.kernel.org ([198.145.29.99]:39902 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731594AbfIHMtn (ORCPT ); Sun, 8 Sep 2019 08:49:43 -0400 Received: from localhost (unknown [62.28.240.114]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 5D836218AC; Sun, 8 Sep 2019 12:49:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567946982; bh=LP2tWWU6SNcc0eaVpBGE6cJjoSO6JWYhOXJUvaUUgV8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IfS0boKZm0gbsCgEjmWv604AMJosNj/0czasfci8Ri4WS2j7JC9Whbi2/NTs4JJ+g YPGxhEEPTWEB+Bg+7Sks4GbRhADNgtnXbjV2Yeb7JYUVl+ZILm0OTMLZXb2tsCNxb0 jg2wv0SWThNW5TI6rEOLMVAHM4NTDpuPnrH5w7uE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Paolo Abeni , Stefano Brivio , Li Shuang , Davide Caratti , "David S. Miller" Subject: [PATCH 5.2 17/94] net/sched: pfifo_fast: fix wrong dereference in pfifo_fast_enqueue Date: Sun, 8 Sep 2019 13:41:13 +0100 Message-Id: <20190908121150.925637761@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190908121150.420989666@linuxfoundation.org> References: <20190908121150.420989666@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Davide Caratti [ Upstream commit 092e22e586236bba106a82113826a68080a03506 ] Now that 'TCQ_F_CPUSTATS' bit can be cleared, depending on the value of 'TCQ_F_NOLOCK' bit in the parent qdisc, we can't assume anymore that per-cpu counters are there in the error path of skb_array_produce(). Otherwise, the following splat can be seen: Unable to handle kernel paging request at virtual address 0000600dea430008 Mem abort info: ESR = 0x96000005 Exception class = DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000005 CM = 0, WnR = 0 user pgtable: 64k pages, 48-bit VAs, pgdp = 000000007b97530e [0000600dea430008] pgd=0000000000000000, pud=0000000000000000 Internal error: Oops: 96000005 [#1] SMP [...] pstate: 10000005 (nzcV daif -PAN -UAO) pc : pfifo_fast_enqueue+0x524/0x6e8 lr : pfifo_fast_enqueue+0x46c/0x6e8 sp : ffff800d39376fe0 x29: ffff800d39376fe0 x28: 1ffff001a07d1e40 x27: ffff800d03e8f188 x26: ffff800d03e8f200 x25: 0000000000000062 x24: ffff800d393772f0 x23: 0000000000000000 x22: 0000000000000403 x21: ffff800cca569a00 x20: ffff800d03e8ee00 x19: ffff800cca569a10 x18: 00000000000000bf x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 x14: ffff1001a726edd0 x13: 1fffe4000276a9a4 x12: 0000000000000000 x11: dfff200000000000 x10: ffff800d03e8f1a0 x9 : 0000000000000003 x8 : 0000000000000000 x7 : 00000000f1f1f1f1 x6 : ffff1001a726edea x5 : ffff800cca56a53c x4 : 1ffff001bf9a8003 x3 : 1ffff001bf9a8003 x2 : 1ffff001a07d1dcb x1 : 0000600dea430000 x0 : 0000600dea430008 Process ping (pid: 6067, stack limit = 0x00000000dc0aa557) Call trace: pfifo_fast_enqueue+0x524/0x6e8 htb_enqueue+0x660/0x10e0 [sch_htb] __dev_queue_xmit+0x123c/0x2de0 dev_queue_xmit+0x24/0x30 ip_finish_output2+0xc48/0x1720 ip_finish_output+0x548/0x9d8 ip_output+0x334/0x788 ip_local_out+0x90/0x138 ip_send_skb+0x44/0x1d0 ip_push_pending_frames+0x5c/0x78 raw_sendmsg+0xed8/0x28d0 inet_sendmsg+0xc4/0x5c0 sock_sendmsg+0xac/0x108 __sys_sendto+0x1ac/0x2a0 __arm64_sys_sendto+0xc4/0x138 el0_svc_handler+0x13c/0x298 el0_svc+0x8/0xc Code: f9402e80 d538d081 91002000 8b010000 (885f7c03) Fix this by testing the value of 'TCQ_F_CPUSTATS' bit in 'qdisc->flags', before dereferencing 'qdisc->cpu_qstats'. Fixes: 8a53e616de29 ("net: sched: when clearing NOLOCK, clear TCQ_F_CPUSTATS, too") CC: Paolo Abeni CC: Stefano Brivio Reported-by: Li Shuang Signed-off-by: Davide Caratti Acked-by: Paolo Abeni Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/sched/sch_generic.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -624,8 +624,12 @@ static int pfifo_fast_enqueue(struct sk_ err = skb_array_produce(q, skb); - if (unlikely(err)) - return qdisc_drop_cpu(skb, qdisc, to_free); + if (unlikely(err)) { + if (qdisc_is_percpu_stats(qdisc)) + return qdisc_drop_cpu(skb, qdisc, to_free); + else + return qdisc_drop(skb, qdisc, to_free); + } qdisc_update_stats_at_enqueue(qdisc, pkt_len); return NET_XMIT_SUCCESS;