From patchwork Tue Mar 31 08:57:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 228650 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=-6.9 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=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 48317C2D0E8 for ; Tue, 31 Mar 2020 09:10:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1EF0520675 for ; Tue, 31 Mar 2020 09:10:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585645846; bh=y6fd+56DXRtMsWE2TPIWeRAL7GDXxJs9T+p42v5SGuo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=h0s1EV4GrLEhAYNvrPaXT2TYv5Xh4p6P4bQBaM8d2mInh91XfTQuSDrzqYnca9X+2 deR+n+/jBD/lx4xK/pHvtT/nRfSRw2DKqiQCVie+F7zbaqkR/gu65lHJqtB7RyWa6/ qdS69xHy2TocCTJf24t3EZl32gHS7H18XvUz3tpY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731611AbgCaJKo (ORCPT ); Tue, 31 Mar 2020 05:10:44 -0400 Received: from mail.kernel.org ([198.145.29.99]:54518 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731624AbgCaJKm (ORCPT ); Tue, 31 Mar 2020 05:10:42 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 1A51920675; Tue, 31 Mar 2020 09:10:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585645842; bh=y6fd+56DXRtMsWE2TPIWeRAL7GDXxJs9T+p42v5SGuo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=olLECaVnp2YiC4llm85QpPMygcKD/gS2A/3/r0XR4iwlJwtitanXCswquU4ofNiy5 d6zLIoa8iVWpgQ/RSHvrfohgf+8HLiTuMKz13KWTdf7GukmWJBXB6E3G71/ljC6YG4 mstZcHptUvBmqtX4HZl1q/WllvoFelNm2XsTzHNU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Qian Cai , David Ahern , "David S. Miller" Subject: [PATCH 5.4 011/155] ipv4: fix a RCU-list lock in inet_dump_fib() Date: Tue, 31 Mar 2020 10:57:31 +0200 Message-Id: <20200331085419.642979289@linuxfoundation.org> X-Mailer: git-send-email 2.26.0 In-Reply-To: <20200331085418.274292403@linuxfoundation.org> References: <20200331085418.274292403@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Qian Cai [ Upstream commit dddeb30bfc43926620f954266fd12c65a7206f07 ] There is a place, inet_dump_fib() fib_table_dump fn_trie_dump_leaf() hlist_for_each_entry_rcu() without rcu_read_lock() will trigger a warning, WARNING: suspicious RCU usage ----------------------------- net/ipv4/fib_trie.c:2216 RCU-list traversed in non-reader section!! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by ip/1923: #0: ffffffff8ce76e40 (rtnl_mutex){+.+.}, at: netlink_dump+0xd6/0x840 Call Trace: dump_stack+0xa1/0xea lockdep_rcu_suspicious+0x103/0x10d fn_trie_dump_leaf+0x581/0x590 fib_table_dump+0x15f/0x220 inet_dump_fib+0x4ad/0x5d0 netlink_dump+0x350/0x840 __netlink_dump_start+0x315/0x3e0 rtnetlink_rcv_msg+0x4d1/0x720 netlink_rcv_skb+0xf0/0x220 rtnetlink_rcv+0x15/0x20 netlink_unicast+0x306/0x460 netlink_sendmsg+0x44b/0x770 __sys_sendto+0x259/0x270 __x64_sys_sendto+0x80/0xa0 do_syscall_64+0x69/0xf4 entry_SYSCALL_64_after_hwframe+0x49/0xb3 Fixes: 18a8021a7be3 ("net/ipv4: Plumb support for filtering route dumps") Signed-off-by: Qian Cai Reviewed-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv4/fib_frontend.c | 2 ++ 1 file changed, 2 insertions(+) --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -1007,7 +1007,9 @@ static int inet_dump_fib(struct sk_buff return -ENOENT; } + rcu_read_lock(); err = fib_table_dump(tb, skb, cb, &filter); + rcu_read_unlock(); return skb->len ? : err; }