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=-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 E0410C2D0FD for ; Wed, 13 May 2020 10:05:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B89B423128 for ; Wed, 13 May 2020 10:05:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589364307; bh=an1QSVmGtJyIXZBH3L/SEKdUB3F4Qr6KkIuZCR+/WDI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ZlikHLefNygwUu1EAldaADVmI5w/vUK1uVk4DY18cmonSsmweJZT9s5zA6nCxN63i bhlLvJ6maTvqEoxqreBPOeIb9rVjzqX4QK7V0GYwwJqbT347UkGQucjEkWO0n8Rfwm WHJuFZQ8aeEt8gHHCkkj52A7aagpJvXTtYlwVLOo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730661AbgEMJrF (ORCPT ); Wed, 13 May 2020 05:47:05 -0400 Received: from mail.kernel.org ([198.145.29.99]:44590 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732730AbgEMJrB (ORCPT ); Wed, 13 May 2020 05:47:01 -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 65B5320740; Wed, 13 May 2020 09:47:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589363220; bh=an1QSVmGtJyIXZBH3L/SEKdUB3F4Qr6KkIuZCR+/WDI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=0XKuEQg/bBYwpKYERnAZYYrYlLjeWk77E4lKszrurh2cRSwta7yMRNZ1+jzeBYZjo T9I8XIa3NG4j8yX0yvHr2CfxYFKTGtx/Msn+fyg0G+QBH77rF4im54uSJpx81Nw1D2 rgB/20qFAEC3FTTHv0+LM4mfPg6U3238LwcjaWf0= 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 4.19 35/48] batman-adv: Fix refcnt leak in batadv_store_throughput_override Date: Wed, 13 May 2020 11:45:01 +0200 Message-Id: <20200513094400.720293748@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200513094351.100352960@linuxfoundation.org> References: <20200513094351.100352960@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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 @@ -1093,7 +1093,7 @@ 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)