Received: by 2002:a25:ca44:0:0:0:0:0 with SMTP id a65csp710868ybg; Tue, 28 Jul 2020 17:25:16 -0700 (PDT) X-Google-Smtp-Source: ABdhPJx3o3mf/aSgjqRnpXLregczx8ZmV9J+fsXtSTYyH09JTBYY582zA3gGjJnDCnpHVkZrP2Ps X-Received: by 2002:a17:906:60c6:: with SMTP id f6mr26370816ejk.265.1595982316477; Tue, 28 Jul 2020 17:25:16 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1595982316; cv=none; d=google.com; s=arc-20160816; b=E9+Gn0jlgdu3kmzcLn14GYe6OLMlTRC/AOFzGzkzvnc3LcnTFbHA1uilv0beSK5yat 2GIsjbFPey5sTkj3nip09cNogTgCuH2GnD51rKvBCCKu4SYiDTOpPTsA314qXrE9QD3n dr+YIcLw8lA3c1ASqFTmhR0j41SlRN9fx/ZLEnE7sqyYxUNnJzVl1kCKxb3J1XIMGNpN FT0X6WMEQzSyqNgAy7H7OjGbuJXQnGlA58AlNlArmdk6D1OlUDlOqYoANbB3bXCtfL+1 DpooUhJDPHfCaSaEm+ZVq0rq/0uI75fvxo0zBoKIULqxgp0FVLXdCfVRWiAG7hYpxCk4 ymrQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding:mime-version :references:in-reply-to:from:subject:cc:to:message-id:date; bh=VLSKx8+e44mmd1axL5W8SEqzXdaJgs2ebnK0UBErXH4=; b=ko2uMJfR4NsA2U+XLGai3IPUsiz6+tZBsi1T2PM46NxQ+NF69o0NEph9KwDEdApyN/ C4S5JD3kH5IBvNMjHpuUCkslHwgo4rWdq8hdQ7Aqi0lxEo4Zf7YxbTKOzsY/u9Ejtq64 UKMemd9/RDmxzu3+UC5oz7q6UtJbdBhOnC7ik2Wh0IFSeFxRD/pOikf/118kSwhE6TYx JTnf33y1fwd8HLtqofl1KB8wI+ntnwO+dKi0M/v2TGaeA8ksENUIsg40PI041vCKC5tP KD84e4KfMBeWHb2B8KWlQMndDa+JREv49KNCrT//gJWYnf8/RfiniZj+q4ftPLPer2xh BIJg== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id l6si258326ede.331.2020.07.28.17.24.54; Tue, 28 Jul 2020 17:25:16 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730594AbgG2AYt (ORCPT + 99 others); Tue, 28 Jul 2020 20:24:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43188 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728236AbgG2AYt (ORCPT ); Tue, 28 Jul 2020 20:24:49 -0400 Received: from shards.monkeyblade.net (shards.monkeyblade.net [IPv6:2620:137:e000::1:9]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2805BC061794; Tue, 28 Jul 2020 17:24:49 -0700 (PDT) Received: from localhost (unknown [IPv6:2601:601:9f00:477::3d5]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 0C1E0128D35D5; Tue, 28 Jul 2020 17:08:03 -0700 (PDT) Date: Tue, 28 Jul 2020 17:24:47 -0700 (PDT) Message-Id: <20200728.172447.1925120854282970312.davem@davemloft.net> To: xiyuyang19@fudan.edu.cn Cc: kuznet@ms2.inr.ac.ru, yoshfuji@linux-ipv6.org, kuba@kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, tanxin.ctf@gmail.com Subject: Re: [PATCH] ipv6: Fix nexthop refcnt leak when creating ipv6 route info From: David Miller In-Reply-To: <1595664139-40703-1-git-send-email-xiyuyang19@fudan.edu.cn> References: <1595664139-40703-1-git-send-email-xiyuyang19@fudan.edu.cn> X-Mailer: Mew version 6.8 on Emacs 26.3 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Tue, 28 Jul 2020 17:08:03 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Xiyu Yang Date: Sat, 25 Jul 2020 16:02:18 +0800 > ip6_route_info_create() invokes nexthop_get(), which increases the > refcount of the "nh". > > When ip6_route_info_create() returns, local variable "nh" becomes > invalid, so the refcount should be decreased to keep refcount balanced. > > The reference counting issue happens in one exception handling path of > ip6_route_info_create(). When nexthops can not be used with source > routing, the function forgets to decrease the refcnt increased by > nexthop_get(), causing a refcnt leak. > > Fix this issue by pulling up the error source routing handling when > nexthops can not be used with source routing. > > Signed-off-by: Xiyu Yang > Signed-off-by: Xin Tan Applied and queued up for -stable, thanks.