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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8E863C433FE for ; Mon, 11 Oct 2021 13:51:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7E24261050 for ; Mon, 11 Oct 2021 13:51:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237275AbhJKNxt (ORCPT ); Mon, 11 Oct 2021 09:53:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:39898 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237397AbhJKNwf (ORCPT ); Mon, 11 Oct 2021 09:52:35 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 0CE48610C8; Mon, 11 Oct 2021 13:50:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1633960235; bh=uF4AiaAvYGbqBcYN+W7w7rNaGLkSNh0jZ1+lV5B6OuI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mbWW4D6cVOfEyNe1os6faxdi/fbMokg4dTIpdbwWI4J+K/8DVuNhMzdrdfG1rczdL vtIVRni/eIaOmt6ajAiXWUGXNdUvEAeviifsMwRvHP/UWP4VXz3dhQJ3pPaNL/BLHP /Y9MXDZsLaUvjdHL/ExHtgU2UjGBk0jibduMuHLA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , Davide Caratti , syzbot , Vinicius Costa Gomes , "David S. Miller" , Sasha Levin Subject: [PATCH 5.4 34/52] net/sched: sch_taprio: properly cancel timer from taprio_destroy() Date: Mon, 11 Oct 2021 15:46:03 +0200 Message-Id: <20211011134504.898485718@linuxfoundation.org> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20211011134503.715740503@linuxfoundation.org> References: <20211011134503.715740503@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Eric Dumazet [ Upstream commit a56d447f196fa9973c568f54c0d76d5391c3b0c0 ] There is a comment in qdisc_create() about us not calling ops->reset() in some cases. err_out4: /* * Any broken qdiscs that would require a ops->reset() here? * The qdisc was never in action so it shouldn't be necessary. */ As taprio sets a timer before actually receiving a packet, we need to cancel it from ops->destroy, just in case ops->reset has not been called. syzbot reported: ODEBUG: free active (active state 0) object type: hrtimer hint: advance_sched+0x0/0x9a0 arch/x86/include/asm/atomic64_64.h:22 WARNING: CPU: 0 PID: 8441 at lib/debugobjects.c:505 debug_print_object+0x16e/0x250 lib/debugobjects.c:505 Modules linked in: CPU: 0 PID: 8441 Comm: syz-executor813 Not tainted 5.14.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:debug_print_object+0x16e/0x250 lib/debugobjects.c:505 Code: ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 af 00 00 00 48 8b 14 dd e0 d3 e3 89 4c 89 ee 48 c7 c7 e0 c7 e3 89 e8 5b 86 11 05 <0f> 0b 83 05 85 03 92 09 01 48 83 c4 18 5b 5d 41 5c 41 5d 41 5e c3 RSP: 0018:ffffc9000130f330 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000 RDX: ffff88802baeb880 RSI: ffffffff815d87b5 RDI: fffff52000261e58 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff815d25ee R11: 0000000000000000 R12: ffffffff898dd020 R13: ffffffff89e3ce20 R14: ffffffff81653630 R15: dffffc0000000000 FS: 0000000000f0d300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffb64b3e000 CR3: 0000000036557000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __debug_check_no_obj_freed lib/debugobjects.c:987 [inline] debug_check_no_obj_freed+0x301/0x420 lib/debugobjects.c:1018 slab_free_hook mm/slub.c:1603 [inline] slab_free_freelist_hook+0x171/0x240 mm/slub.c:1653 slab_free mm/slub.c:3213 [inline] kfree+0xe4/0x540 mm/slub.c:4267 qdisc_create+0xbcf/0x1320 net/sched/sch_api.c:1299 tc_modify_qdisc+0x4c8/0x1a60 net/sched/sch_api.c:1663 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5571 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x86d/0xdb0 net/netlink/af_netlink.c:1929 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:724 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2403 ___sys_sendmsg+0xf3/0x170 net/socket.c:2457 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2486 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 Fixes: 44d4775ca518 ("net/sched: sch_taprio: reset child qdiscs before freeing them") Signed-off-by: Eric Dumazet Cc: Davide Caratti Reported-by: syzbot Acked-by: Vinicius Costa Gomes Acked-by: Davide Caratti Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/sched/sch_taprio.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/net/sched/sch_taprio.c b/net/sched/sch_taprio.c index da9ed0613eb7..e14a66ce4884 100644 --- a/net/sched/sch_taprio.c +++ b/net/sched/sch_taprio.c @@ -1630,6 +1630,10 @@ static void taprio_destroy(struct Qdisc *sch) list_del(&q->taprio_list); spin_unlock(&taprio_list_lock); + /* Note that taprio_reset() might not be called if an error + * happens in qdisc_create(), after taprio_init() has been called. + */ + hrtimer_cancel(&q->advance_timer); taprio_disable_offload(dev, q, NULL); -- 2.33.0