From patchwork Mon Feb 1 20:00:49 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexander Ovechkin X-Patchwork-Id: 12060017 X-Patchwork-Delegate: kuba@kernel.org 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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 9F726C433DB for ; Mon, 1 Feb 2021 20:02:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6501364EA2 for ; Mon, 1 Feb 2021 20:02:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233111AbhBAUCb (ORCPT ); Mon, 1 Feb 2021 15:02:31 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43908 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232973AbhBAUBx (ORCPT ); Mon, 1 Feb 2021 15:01:53 -0500 Received: from forwardcorp1o.mail.yandex.net (forwardcorp1o.mail.yandex.net [IPv6:2a02:6b8:0:1a2d::193]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 94CA8C061573 for ; Mon, 1 Feb 2021 12:01:01 -0800 (PST) Received: from sas1-ec30c78b6c5b.qloud-c.yandex.net (sas1-ec30c78b6c5b.qloud-c.yandex.net [IPv6:2a02:6b8:c14:2704:0:640:ec30:c78b]) by forwardcorp1o.mail.yandex.net (Yandex) with ESMTP id D9A792E148A; Mon, 1 Feb 2021 23:00:58 +0300 (MSK) Received: from sas2-d40aa8807eff.qloud-c.yandex.net (sas2-d40aa8807eff.qloud-c.yandex.net [2a02:6b8:c08:b921:0:640:d40a:a880]) by sas1-ec30c78b6c5b.qloud-c.yandex.net (mxbackcorp/Yandex) with ESMTP id aN76oZVRFS-0v0WbxMi; Mon, 01 Feb 2021 23:00:58 +0300 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex-team.ru; s=default; t=1612209658; bh=y+9wyeryFCpGlLpD1IBoTLqw0vGCUaomyPqU83N+3bo=; h=Message-Id:Date:Subject:To:From:Cc; b=iyrdK0Gdj6JWxukB2EWitrMiI7gtac1NMyqCVg7T4DbGIWZDhl4S8srV6xZQJYE5q ZmgzXMU/ZXG+G6hMt7dZrRmOzP7Av2ZCK0ddmCtA5r0BA4jZjMnDczXdMGjmzl7Gvl AGgdU8/WW2FkCdKWyQxxWyD0iuO4ubiH1rjxIulM= Authentication-Results: sas1-ec30c78b6c5b.qloud-c.yandex.net; dkim=pass header.i=@yandex-team.ru Received: from ov.sas.yp-c.yandex.net (ov.sas.yp-c.yandex.net [2a02:6b8:c1b:2921:0:696:dfec:0]) by sas2-d40aa8807eff.qloud-c.yandex.net (smtpcorp/Yandex) with ESMTPSA id VOF88UJSGP-0vn41nDs; Mon, 01 Feb 2021 23:00:57 +0300 (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (Client certificate not present) From: Alexander Ovechkin To: netdev@vger.kernel.org Cc: pabeni@redhat.com, davem@davemloft.net, kuba@kernel.org, jhs@mojatatu.com, xiyou.wangcong@gmail.com, zeil@yandex-team.ru, dmtrmonakhov@yandex-team.ru Subject: [PATCH net] net: sched: replaced invalid qdisc tree flush helper in qdisc_replace Date: Mon, 1 Feb 2021 23:00:49 +0300 Message-Id: <20210201200049.299153-1-ovov@yandex-team.ru> Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org Commit e5f0e8f8e456 ("net: sched: introduce and use qdisc tree flush/purge helpers") introduced qdisc tree flush/purge helpers, but erroneously used flush helper instead of purge helper in qdisc_replace function. This issue was found in our CI, that tests various qdisc setups by configuring qdisc and sending data through it. Call of invalid helper sporadically leads to corruption of vt_tree/cf_tree of hfsc_class that causes kernel oops: Oops: 0000 [#1] SMP PTI CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.11.0-8f6859df #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.2-0-g5f4c7b1-prebuilt.qemu-project.org 04/01/2014 RIP: 0010:rb_insert_color+0x18/0x190 Code: c3 31 c0 c3 0f 1f 40 00 66 2e 0f 1f 84 00 00 00 00 00 48 8b 07 48 85 c0 0f 84 05 01 00 00 48 8b 10 f6 c2 01 0f 85 34 01 00 00 <48> 8b 4a 08 49 89 d0 48 39 c1 74 7d 48 85 c9 74 32 f6 01 01 75 2d RSP: 0018:ffffc900000b8bb0 EFLAGS: 00010246 RAX: ffff8881ef4c38b0 RBX: ffff8881d956e400 RCX: ffff8881ef4c38b0 RDX: 0000000000000000 RSI: ffff8881d956f0a8 RDI: ffff8881d956e4b0 RBP: 0000000000000000 R08: 000000d5c4e249da R09: 1600000000000000 R10: ffffc900000b8be0 R11: ffffc900000b8b28 R12: 0000000000000001 R13: 000000000000005a R14: ffff8881f0905000 R15: ffff8881f0387d00 FS: 0000000000000000(0000) GS:ffff8881f8b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000008 CR3: 00000001f4796004 CR4: 0000000000060ee0 Call Trace: init_vf.isra.19+0xec/0x250 [sch_hfsc] hfsc_enqueue+0x245/0x300 [sch_hfsc] ? fib_rules_lookup+0x12a/0x1d0 ? __dev_queue_xmit+0x4b6/0x930 ? hfsc_delete_class+0x250/0x250 [sch_hfsc] __dev_queue_xmit+0x4b6/0x930 ? ip6_finish_output2+0x24d/0x590 ip6_finish_output2+0x24d/0x590 ? ip6_output+0x6c/0x130 ip6_output+0x6c/0x130 ? __ip6_finish_output+0x110/0x110 mld_sendpack+0x224/0x230 mld_ifc_timer_expire+0x186/0x2c0 ? igmp6_group_dropped+0x200/0x200 call_timer_fn+0x2d/0x150 run_timer_softirq+0x20c/0x480 ? tick_sched_do_timer+0x60/0x60 ? tick_sched_timer+0x37/0x70 __do_softirq+0xf7/0x2cb irq_exit+0xa0/0xb0 smp_apic_timer_interrupt+0x74/0x150 apic_timer_interrupt+0xf/0x20 Fixes: e5f0e8f8e456 ("net: sched: introduce and use qdisc tree flush/purge helpers") Signed-off-by: Alexander Ovechkin Reported-by: Alexander Kuznetsov Acked-by: Dmitry Monakhov Acked-by: Dmitry Yakunin Acked-by: Cong Wang --- include/net/sch_generic.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h index 3d03756e1069..b2ceec7b280d 100644 --- a/include/net/sch_generic.h +++ b/include/net/sch_generic.h @@ -1158,7 +1158,7 @@ static inline struct Qdisc *qdisc_replace(struct Qdisc *sch, struct Qdisc *new, old = *pold; *pold = new; if (old != NULL) - qdisc_tree_flush_backlog(old); + qdisc_purge_queue(old); sch_tree_unlock(sch); return old;