From patchwork Wed May 13 09:45:13 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 225990 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 11F38C2D0F9 for ; Wed, 13 May 2020 09:55:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DF56A23128 for ; Wed, 13 May 2020 09:55:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589363715; bh=t+dAG2ciSY11/anwEimjtMYFr2ia36uqkw+4TtFXdvI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=cEAcWgRKeAKSR0XkkNpkXPhwjoH18AohnLQNnBrvjKHteM/Nn2RzVGLYjIA7Z71Re 9t8UPsBxaakdmDujndbVHJm/t2lUjJdw2JtV7O37g2zZOddCg9i+05HpKsVQaPWntE xWsV6nWanFzoZmrY50GmeMgU93Se6C2IpyYj65ss= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387739AbgEMJzO (ORCPT ); Wed, 13 May 2020 05:55:14 -0400 Received: from mail.kernel.org ([198.145.29.99]:58124 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387681AbgEMJzN (ORCPT ); Wed, 13 May 2020 05:55:13 -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 1DD7220753; Wed, 13 May 2020 09:55:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589363712; bh=t+dAG2ciSY11/anwEimjtMYFr2ia36uqkw+4TtFXdvI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=AkugV0PKxlvssvh82iagRhIuq165x/oeDh/Pvd6jkIir2EIyPrpm/T24RPm5F8IHW IP8Dg1moZGeNLHk/m4X6unfrWz9l6W+MOY22kR33Jacvq/wkxZnZrKLuV2AaoFjB6L osBU0V1a/9FGSSbYyQtapRN5TJjmAS8kO/i5CloE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Xiyu Yang , Xin Tan , Sven Eckelmann , Simon Wunderlich Subject: [PATCH 5.6 094/118] batman-adv: Fix refcnt leak in batadv_store_throughput_override Date: Wed, 13 May 2020 11:45:13 +0200 Message-Id: <20200513094425.545848374@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200513094417.618129545@linuxfoundation.org> References: <20200513094417.618129545@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: Xiyu Yang commit 6107c5da0fca8b50b4d3215e94d619d38cc4a18c upstream. batadv_show_throughput_override() invokes batadv_hardif_get_by_netdev(), which gets a batadv_hard_iface object from net_dev with increased refcnt and its reference is assigned to a local pointer 'hard_iface'. When batadv_store_throughput_override() returns, "hard_iface" becomes invalid, so the refcount should be decreased to keep refcount balanced. The issue happens in one error path of batadv_store_throughput_override(). When batadv_parse_throughput() returns NULL, the refcnt increased by batadv_hardif_get_by_netdev() is not decreased, causing a refcnt leak. Fix this issue by jumping to "out" label when batadv_parse_throughput() returns NULL. Fixes: 0b5ecc6811bd ("batman-adv: add throughput override attribute to hard_ifaces") Signed-off-by: Xiyu Yang Signed-off-by: Xin Tan Signed-off-by: Sven Eckelmann Signed-off-by: Simon Wunderlich Signed-off-by: Greg Kroah-Hartman --- net/batman-adv/sysfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/net/batman-adv/sysfs.c +++ b/net/batman-adv/sysfs.c @@ -1150,7 +1150,7 @@ static ssize_t batadv_store_throughput_o ret = batadv_parse_throughput(net_dev, buff, "throughput_override", &tp_override); if (!ret) - return count; + goto out; old_tp_override = atomic_read(&hard_iface->bat_v.throughput_override); if (old_tp_override == tp_override)