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=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS, T_DKIMWL_WL_HIGH,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 D1A60C004C9 for ; Tue, 7 May 2019 06:02:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9FC3C21019 for ; Tue, 7 May 2019 06:02:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557208927; bh=n2l7YfpgID2UQ6/kBqlqEoPn+qsA5W25cTlr72n7AkA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=C+pNvfPPCdkFqBlyE1cw2n0rPGlckPBNw4T9kPfYzVmY5G1X95XD7D1jHrQ4doola ltHD02JGIhhf5iYkkod73LXWt4GsCBAHwL5L85UC3XsbzVgSxBWAqlDAHDAfIGfngj KExqeHGw7C5ST9KR3Ju9YjjQdYJZDPM7xVxJRv1I= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727892AbfEGFft (ORCPT ); Tue, 7 May 2019 01:35:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:55746 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727388AbfEGFfq (ORCPT ); Tue, 7 May 2019 01:35:46 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C8B262087F; Tue, 7 May 2019 05:35:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557207345; bh=n2l7YfpgID2UQ6/kBqlqEoPn+qsA5W25cTlr72n7AkA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CF+GF1/q3x5rDM5iYMSMNeyVMf3XpCXPEbr8KJ+is25IesMZLSjEP4tziJzWPty8U V8nwPdtpeWYZ3Edb6RdwOSLWrCkm0gasNAQGxdm3TF6bcwWY8tmZnqhDcKzbakO7o4 jBx+7hG0BszW8r+r98tZalP/r8FfjZbjqCWaI/08= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: John Hurley , Jakub Kicinski , Cong Wang , "David S . Miller" , Sasha Levin , netdev@vger.kernel.org Subject: [PATCH AUTOSEL 5.0 97/99] net: sched: fix cleanup NULL pointer exception in act_mirr Date: Tue, 7 May 2019 01:32:31 -0400 Message-Id: <20190507053235.29900-97-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190507053235.29900-1-sashal@kernel.org> References: <20190507053235.29900-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: John Hurley [ Upstream commit 064c5d6881e897077639e04973de26440ee205e6 ] A new mirred action is created by the tcf_mirred_init function. This contains a list head struct which is inserted into a global list on successful creation of a new action. However, after a creation, it is still possible to error out and call the tcf_idr_release function. This, in turn, calls the act_mirr cleanup function via __tcf_idr_release and __tcf_action_put. This cleanup function tries to delete the list entry which is as yet uninitialised, leading to a NULL pointer exception. Fix this by initialising the list entry on creation of a new action. Bug report: BUG: unable to handle kernel NULL pointer dereference at 0000000000000008 PGD 8000000840c73067 P4D 8000000840c73067 PUD 858dcc067 PMD 0 Oops: 0002 [#1] SMP PTI CPU: 32 PID: 5636 Comm: handler194 Tainted: G OE 5.0.0+ #186 Hardware name: Dell Inc. PowerEdge R730/0599V5, BIOS 1.3.6 06/03/2015 RIP: 0010:tcf_mirred_release+0x42/0xa7 [act_mirred] Code: f0 90 39 c0 e8 52 04 57 c8 48 c7 c7 b8 80 39 c0 e8 94 fa d4 c7 48 8b 93 d0 00 00 00 48 8b 83 d8 00 00 00 48 c7 c7 f0 90 39 c0 <48> 89 42 08 48 89 10 48 b8 00 01 00 00 00 00 ad de 48 89 83 d0 00 RSP: 0018:ffffac4aa059f688 EFLAGS: 00010282 RAX: 0000000000000000 RBX: ffff9dcd1b214d00 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff9dcd1fa165f8 RDI: ffffffffc03990f0 RBP: ffff9dccf9c7af80 R08: 0000000000000a3b R09: 0000000000000000 R10: ffff9dccfa11f420 R11: 0000000000000000 R12: 0000000000000001 R13: ffff9dcd16b433c0 R14: ffff9dcd1b214d80 R15: 0000000000000000 FS: 00007f441bfff700(0000) GS:ffff9dcd1fa00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000008 CR3: 0000000839e64004 CR4: 00000000001606e0 Call Trace: tcf_action_cleanup+0x59/0xca __tcf_action_put+0x54/0x6b __tcf_idr_release.cold.33+0x9/0x12 tcf_mirred_init.cold.20+0x22e/0x3b0 [act_mirred] tcf_action_init_1+0x3d0/0x4c0 tcf_action_init+0x9c/0x130 tcf_exts_validate+0xab/0xc0 fl_change+0x1ca/0x982 [cls_flower] tc_new_tfilter+0x647/0x8d0 ? load_balance+0x14b/0x9e0 rtnetlink_rcv_msg+0xe3/0x370 ? __switch_to_asm+0x40/0x70 ? __switch_to_asm+0x34/0x70 ? _cond_resched+0x15/0x30 ? __kmalloc_node_track_caller+0x1d4/0x2b0 ? rtnl_calcit.isra.31+0xf0/0xf0 netlink_rcv_skb+0x49/0x110 netlink_unicast+0x16f/0x210 netlink_sendmsg+0x1df/0x390 sock_sendmsg+0x36/0x40 ___sys_sendmsg+0x27b/0x2c0 ? futex_wake+0x80/0x140 ? do_futex+0x2b9/0xac0 ? ep_scan_ready_list.constprop.22+0x1f2/0x210 ? ep_poll+0x7a/0x430 __sys_sendmsg+0x47/0x80 do_syscall_64+0x55/0x100 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: 4e232818bd32 ("net: sched: act_mirred: remove dependency on rtnl lock") Signed-off-by: John Hurley Reviewed-by: Jakub Kicinski Acked-by: Cong Wang Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/sched/act_mirred.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c index c8cf4d10c435..971dc03304f4 100644 --- a/net/sched/act_mirred.c +++ b/net/sched/act_mirred.c @@ -159,6 +159,9 @@ static int tcf_mirred_init(struct net *net, struct nlattr *nla, } m = to_mirred(*a); + if (ret == ACT_P_CREATED) + INIT_LIST_HEAD(&m->tcfm_list); + spin_lock_bh(&m->tcf_lock); m->tcf_action = parm->action; m->tcfm_eaction = parm->eaction; -- 2.20.1